Sample records for apparent false negative

  1. The false-negative Meckel's scan

    SciTech Connect

    Wilton, G.; Froelich, J.W.

    1982-10-01

    A case is presented of a 17-month-old girl who underwent two Meckel's scans with /sup 99m/Tc pertechnetate. The initial study was interpreted as normal while a subsequent study five days later was definitely positive. Surgery immediately following the positive Meckel's scan demonstrated a Meckel's diverticulum containing gastric mucosa without evidence of active hemorrhage. This prompted a review of the literature in reference to false-negative Meckel's scans which revealed a wide variance in the reported incidence of false-negative examinations. Repeat scintigraphy in the face of a strong clinical suspicion after an initial normal study may decrease the indicence of false-negative imaging series.

  2. How does negative emotion cause false memories?

    PubMed

    Brainerd, C J; Stein, L M; Silveira, R A; Rohenkohl, G; Reyna, V F

    2008-09-01

    Remembering negative events can stimulate high levels of false memory, relative to remembering neutral events. In experiments in which the emotional valence of encoded materials was manipulated with their arousal levels controlled, valence produced a continuum of memory falsification. Falsification was highest for negative materials, intermediate for neutral materials, and lowest for positive materials. Conjoint-recognition analysis produced a simple process-level explanation: As one progresses from positive to neutral to negative valence, false memory increases because (a) the perceived meaning resemblance between false and true items increases and (b) subjects are less able to use verbatim memories of true items to suppress errors. PMID:18947358

  3. Accounting for false negatives in hotspot detection

    SciTech Connect

    Sego, Landon H.; Wilson, John E.

    2007-08-28

    Hotspot sampling designs are used in environmental sampling to identify the location of one (or more) contiguous regions of elevated contamination. These regions are known as hotspots. The problem of how to calculate the probability of detecting an elliptical hotspot using a rectangular or triangular grid of sampling points was addressed by Singer and Wickman in 1969. This approach presumed that any sample which coincided with a hotspot would detect the hotspot without error. However, for many sampling methodologies, there is a chance that the hotspot will not be detected even though it has been sampled directly--a false negative. We present a mathematical solution and a numerical algorithm which account for false negatives when calculating the probability of detecting hotspots that are circular in shape.

  4. A Closer Look at Self-Reported Suicide Attempts: False Positives and False Negatives

    ERIC Educational Resources Information Center

    Ploderl, Martin; Kralovec, Karl; Yazdi, Kurosch; Fartacek, Reinhold

    2011-01-01

    The validity of self-reported suicide attempt information is undermined by false positives (e.g., incidences without intent to die), or by unreported suicide attempts, referred to as false negatives. In a sample of 1,385 Austrian adults, we explored the occurrence of false positives and false negatives with detailed, probing questions. Removing…

  5. Rh genotyping: avoiding false-negative and false-positive results among individuals of African ancestry.

    PubMed

    Ekman, G C; Billingsly, R; Hessner, M J

    2002-01-01

    High homology, variant alleles, and silent alleles have made the development of completely reliable genotyping assays for the RHD and RHC alleles difficult. An RHD pseudogene (RHDPsi) possessing a 37-bp insertion within exon 4 is common among serologically RhD-negative individuals of African descent and generates false-positive results in previously reported RhD genotyping assays. Genotyping RhC is problematic due to exon 2 homology between RHD and RHC; however, an RHC-specific 109-bp insertion within intron 2 has been reported useful for genotyping. Primers flanking the exon 4 insertion point were used for detection of RHD and RHDPsi among a total of 231 serotyped individuals: 134 African American, 85 Caucasian, and 12 RhD serotype-negative/genotype-positive, D-sensitized women. Primers flanking the RHC-specific intron 2 insertion were used to genotype 282 serotyped individuals (128 African American, 154 Caucasian) and were compared to RHC genotyping using the exon 1 RhC-specific nt48 cytosine polymorphism. Complete correlation was observed between genotyping with the RHDPsi primer pair and serotyping among 219 individuals and 10/12 previous RHD false-positive genotyping results were resolved. RHDPsi was detected in 19% (n = 4/21) of RhD seronegative African Americans and 4.4% (n = 5/113) of RhD seropositive African Americans. When using the 109-bp intron 2 insertion for genotyping of RHC, a 23.9% (n = 11/46) false-negative rate was observed among African American RhCc serotyped heterozygotes. Utilization of the exon 1 nt48 cytosine for indirect genotyping of RHC yielded a 7.2% (n = 4/55) and 56.3% (n = 45/80) false-positive rate among Rhcc Caucasians and African Americans, respectively. We conclude that these additional reactions, though not sufficient alone, can be useful supplements to existing Rh genotyping assays. PMID:11835329

  6. Using sniffing behavior to differentiate true negative from false negative responses in trained scent-detection dogs.

    PubMed

    Concha, Astrid; Mills, Daniel S; Feugier, Alexandre; Zulch, Helen; Guest, Claire; Harris, Rob; Pike, Thomas W

    2014-11-01

    False negatives are recorded in every chemical detection system, but when animals are used as a scent detector, some false negatives can arise as a result of a failure in the link between detection and the trained alert response, or a failure of the handler to identify the positive alert. A false negative response can be critical in certain scenarios, such as searching for a live person or detecting explosives. In this study, we investigated whether the nature of sniffing behavior in trained detection dogs during a controlled scent-detection task differs in response to true positives, true negatives, false positives, and false negatives. A total of 200 videos of 10 working detection dogs were pseudorandomly selected and analyzed frame by frame to quantify sniffing duration and the number of sniffing episodes recorded in a Go/No-Go single scent-detection task using an eight-choice test apparatus. We found that the sniffing duration of true negatives is significantly shorter than false negatives, true positives, and false positives. Furthermore, dogs only ever performed one sniffing episode towards true negatives, but two sniffing episodes commonly occurred in the other situations. These results demonstrate how the nature of sniffing can be used to more effectively assess odor detection by dogs used as biological detection devices. PMID:25214467

  7. False Negatives in Sexual Abuse Interviews: Preliminary Investigation of a Relationship to Dissociation.

    ERIC Educational Resources Information Center

    Chaffin, Mark; Lawson, Louanne; Selby, Abby; Wherry, Jeffrey N.

    1997-01-01

    Reports on girls (n=5) who had been sexually abused but had failed to disclose any sexual contact in a sexual-abuse disclosure interview (false negatives). Results indicate that false negative children had significantly higher levels of dissociative symptoms when compared to "true positive" abused children and non-abused children. (RJM)

  8. INCIDENCE AND CLINICAL SIGNIFICANCE OF FALSE-NEGATIVE SEXTANT PROSTATE BIOPSIES

    Microsoft Academic Search

    FARHANG RABBANI; NICHOLAS STROUMBAKIS; BRUCE R. KAVA; MICHAEL S. COOKSON; WILLIAM R. FAIR

    1998-01-01

    PurposeSince most patients do not undergo repeat sextant prostate biopsies after a biopsy is positive for prostate cancer, the true incidence of false-negative biopsies is not well defined. We assess the incidence and clinical significance of false-negative sextant prostate biopsies in patients undergoing radical prostatectomy.

  9. Human papillomavirus in false negative archival cervical smears: implications for screening for cervical cancer

    Microsoft Academic Search

    J M Walboomers; A M de Roda Husman; P J Snijders; H V Stel; E K Risse; T J Helmerhorst; F J Voorhorst; C J Meijer

    1995-01-01

    AIM--To assess the value of detecting human papillomavirus (HPV) DNA in false negative archival cervical smears in population based screening programmes for cervical cancer. METHODS--Cytomorphologically classified false negative archival Pap smears (n = 27) taken from 18 women up to six years before cervical cancer was diagnosed were blindly mixed with 89 smears from hospital patients with a variety of

  10. Negative feedback from maternal signals reduces false alarms by collectively signalling offspring

    PubMed Central

    Hamel, Jennifer A.; Cocroft, Reginald B.

    2012-01-01

    Within animal groups, individuals can learn of a predator's approach by attending to the behaviour of others. This use of social information increases an individual's perceptual range, but can also lead to the propagation of false alarms. Error copying is especially likely in species that signal collectively, because the coordination required for collective displays relies heavily on social information. Recent evidence suggests that collective behaviour in animals is, in part, regulated by negative feedback. Negative feedback may reduce false alarms by collectively signalling animals, but this possibility has not yet been tested. We tested the hypothesis that negative feedback increases the accuracy of collective signalling by reducing the production of false alarms. In the treehopper Umbonia crassicornis, clustered offspring produce collective signals during predator attacks, advertising the predator's location to the defending mother. Mothers signal after evicting the predator, and we show that this maternal communication reduces false alarms by offspring. We suggest that maternal signals elevate offspring signalling thresholds. This is, to our knowledge, the first study to show that negative feedback can reduce false alarms by collectively behaving groups. PMID:22787019

  11. A Simple Strategy for Reducing False Negatives in Calling Variants from Single-Cell Sequencing Data

    PubMed Central

    Ji, Cong; Miao, Zong; He, Xionglei

    2015-01-01

    Due to the growth of interest in single-cell genomics, computational methods for distinguishing true variants from artifacts are highly desirable. While special attention has been paid to false positives in variant or mutation calling from single-cell sequencing data, an equally important but often neglected issue is that of false negatives derived from allele dropout during the amplification of single cell genomes. In this paper, we propose a simple strategy to reduce the false negatives in single-cell sequencing data analysis. Simulation results show that this method is highly reliable, with an error rate of 4.94×10-5, which is orders of magnitude lower than the expected false negative rate (~34%) estimated from a single-cell exome dataset, though the method is limited by the low SNP density in the human genome. We applied this method to analyze the exome data of a few dozen single tumor cells generated in previous studies, and extracted cell specific mutation information for a small set of sites. Interestingly, we found that there are difficulties in using the classical clonal model of tumor cell growth to explain the mutation patterns observed in some tumor cells. PMID:25876174

  12. False-negative dipyridamole-thallium-201 myocardial imaging after caffeine infusion

    SciTech Connect

    Smits, P.; Corstens, F.H.; Aengevaeren, W.R.; Wackers, F.J.; Thien, T. (University Hospital Nijmegen (Netherlands))

    1991-08-01

    The vasodilator effect of intravenously administered dipyridamole may be caused by an increase in endogenous plasma adenosine levels. The authors evaluated the effect of caffeine, an adenosine receptor antagonist, on the diagnostic results of dipyridamole-201Tl myocardial imaging in eight patients with coronary artery disease. Caffeine infusion significantly attenuated the dipyridamole-induced fall in blood pressure and the accompanied increase in heart rate. The infusion of dipyridamole alone resulted in chest pain and ST-segment depressions on the electrocardiogram in four patients, whereas none of these problems occurred when the tests were repeated after caffeine. In six of eight patients, caffeine was responsible for false-negative dipyridamole-201Tl tests. Semiquantitive scores of the dipyridamole-induced 201Tl perfusion defects were decreased by caffeine from 9.0 {plus minus} 0.9 to 2.0 {plus minus} 1.1 points (p less than 0.05). Computerized analysis revealed a caffeine-mediated reduction in the percent reversibility of the images from 46% {plus minus} 16% to 6% {plus minus} 10% (p less than 0.05). They conclude that the use of caffeinated products prior to dipyridamole-201Tl testing may be responsible for false-negative findings.

  13. An investigation into false-negative transthoracic fine needle aspiration and core biopsy specimens.

    PubMed

    Minot, Douglas M; Gilman, Elizabeth A; Aubry, Marie-Christine; Voss, Jesse S; Van Epps, Sarah G; Tuve, Delores J; Sciallis, Andrew P; Henry, Michael R; Salomao, Diva R; Lee, Peter; Carlson, Stephanie K; Clayton, Amy C

    2014-12-01

    Transthoracic fine needle aspiration (TFNA)/core needle biopsy (CNB) under computed tomography (CT) guidance has proved useful in the assessment of pulmonary nodules. We sought to determine the TFNA false-negative (FN) rate at our institution and identify potential causes of FN diagnoses. Medical records were reviewed from 1,043 consecutive patients who underwent CT-guided TFNA with or without CNB of lung nodules over a 5-year time period (2003-2007). Thirty-seven FN cases of "negative" TFNA/CNB with malignant outcome were identified with 36 cases available for review, of which 35 had a corresponding CNB. Cases were reviewed independently (blinded to original diagnosis) by three pathologists with 15 age- and sex-matched positive and negative controls. Diagnosis (i.e., nondiagnostic, negative or positive for malignancy, atypical or suspicious) and qualitative assessments were recorded. Consensus diagnosis was suspicious or positive in 10 (28%) of 36 TFNA cases and suspicious in 1 (3%) of 35 CNB cases, indicating potential interpretive errors. Of the 11 interpretive errors (including both suspicious and positive cases), 8 were adenocarcinomas, 1 squamous cell carcinoma, 1 metastatic renal cell carcinoma, and 1 lymphoma. The remaining 25 FN cases (69.4%) were considered sampling errors and consisted of 7 adenocarcinomas, 3 nonsmall cell carcinomas, 3 lymphomas, 2 squamous cell carcinomas, and 2 renal cell carcinomas. Interpretive and sampling error cases were more likely to abut the pleura, while histopathologically, they tended to be necrotic and air-dried. The overall FN rate in this patient cohort is 3.5% (1.1% interpretive and 2.4% sampling errors). PMID:24866385

  14. Technetium-99m white blood cell imaging: False-negative result in salmonella osteomyelitis associated with sickle cell disease

    SciTech Connect

    Guze, B.H.; Hawkins, R.A.; Marcus, C.S.

    1989-02-01

    The authors report a case of sickle cell anemia associated osteomyelitis where the Tc-99m white blood cell imaging was negative, and bone imaging showed increased uptake in the region in question. The reasons for the possible false-negative image are discussed.

  15. A highly sensitive telomerase activity assay that eliminates false-negative results caused by PCR inhibitors.

    PubMed

    Yaku, Hidenobu; Murashima, Takashi; Miyoshi, Daisuke; Sugimoto, Naoki

    2013-01-01

    An assay for telomerase activity based on asymmetric polymerase chain reaction (A-PCR) on magnetic beads (MBs) and subsequent application of cycling probe technology (CPT) is described. In this assay, the telomerase reaction products are immobilized on MBs, which are then washed to remove PCR inhibitors that are commonly found in clinical samples. The guanine-rich sequences (5'-(TTAGGG)n-3') of the telomerase reaction products are then preferentially amplified by A-PCR, and the amplified products are subsequently detected via CPT, where a probe RNA with a fluorophore at the 5' end and a quencher at the 3' end is hydrolyzed by RNase H in the presence of the target DNA. The catalyst-mediated cleavage of the probe RNA enhances fluorescence from the 5' end of the probe. The assay allowed us to successfully detect HeLa cells selectively over normal human dermal fibroblast (NHDF) cells. Importantly, this selectivity produced identical results with regard to detection of HeLa cells in the absence and presence of excess NHDF cells; therefore, this assay can be used for practical clinical applications. The lower limit of detection for HeLa cells was 50 cells, which is lower than that achieved with a conventional telomeric repeat amplification protocol assay. Our assay also eliminated false-negative results caused by PCR inhibitors. Furthermore, we show that this assay is appropriate for screening among G-quadruplex ligands to find those that inhibit telomerase activity. PMID:24071983

  16. False-Negative Rate of Gram-Stain Microscopy for Diagnosis of Septic Arthritis: Suggestions for Improvement

    PubMed Central

    Amanat, Suheil; Ahmed, Abdulkhaled; Armstrong, Malcolm; Sharma, Pankaj; Qamruddin, Ahmed

    2014-01-01

    We quantify the false-negative diagnostic rate of septic arthritis using Gram-stain microscopy of synovial fluid and compare this to values reported in the peer-reviewed literature. We propose a method of improving the diagnostic value of Gram-stain microscopy using Lithium Heparin containers that prevent synovial fluid coagulation. Retrospective study of the Manchester Royal Infirmary microbiology database of patients undergoing synovial fluid Gram-stain and culture between December 2003 and March 2012 was undertaken. The initial cohort of 1896 synovial fluid analyses for suspected septic arthritis was reduced to 143 after exclusion criteria were applied. Analysis of our Gram-stain microscopy yielded 111 false-negative results from a cohort size of 143 positive synovial fluid cultures, giving a false-negative rate of 78%. We report a false-negative rate of Gram-stain microscopy for septic arthritis of 78%. Clinicians should therefore avoid the investigation until a statistically significant data set confirms its efficacy. The investigation's value could be improved by using Lithium Heparin containers to collect homogenous synovial fluid samples. Ongoing research aims to establish how much this could reduce the false-negative rate. PMID:24678320

  17. False-negative rate of gram-stain microscopy for diagnosis of septic arthritis: suggestions for improvement.

    PubMed

    Stirling, Paul; Faroug, Radwane; Amanat, Suheil; Ahmed, Abdulkhaled; Armstrong, Malcolm; Sharma, Pankaj; Qamruddin, Ahmed

    2014-01-01

    We quantify the false-negative diagnostic rate of septic arthritis using Gram-stain microscopy of synovial fluid and compare this to values reported in the peer-reviewed literature. We propose a method of improving the diagnostic value of Gram-stain microscopy using Lithium Heparin containers that prevent synovial fluid coagulation. Retrospective study of the Manchester Royal Infirmary microbiology database of patients undergoing synovial fluid Gram-stain and culture between December 2003 and March 2012 was undertaken. The initial cohort of 1896 synovial fluid analyses for suspected septic arthritis was reduced to 143 after exclusion criteria were applied. Analysis of our Gram-stain microscopy yielded 111 false-negative results from a cohort size of 143 positive synovial fluid cultures, giving a false-negative rate of 78%. We report a false-negative rate of Gram-stain microscopy for septic arthritis of 78%. Clinicians should therefore avoid the investigation until a statistically significant data set confirms its efficacy. The investigation's value could be improved by using Lithium Heparin containers to collect homogenous synovial fluid samples. Ongoing research aims to establish how much this could reduce the false-negative rate. PMID:24678320

  18. False-Negative Rate and Recovery Efficiency Performance of a Validated Sponge Wipe Sampling Method

    PubMed Central

    Piepel, Greg F.; Boucher, Raymond; Tezak, Matt; Amidan, Brett G.; Einfeld, Wayne

    2012-01-01

    Recovery of spores from environmental surfaces varies due to sampling and analysis methods, spore size and characteristics, surface materials, and environmental conditions. Tests were performed to evaluate a new, validated sponge wipe method using Bacillus atrophaeus spores. Testing evaluated the effects of spore concentration and surface material on recovery efficiency (RE), false-negative rate (FNR), limit of detection (LOD), and their uncertainties. Ceramic tile and stainless steel had the highest mean RE values (48.9 and 48.1%, respectively). Faux leather, vinyl tile, and painted wood had mean RE values of 30.3, 25.6, and 25.5, respectively, while plastic had the lowest mean RE (9.8%). Results show roughly linear dependences of RE and FNR on surface roughness, with smoother surfaces resulting in higher mean REs and lower FNRs. REs were not influenced by the low spore concentrations tested (3.10 × 10?3 to 1.86 CFU/cm2). Stainless steel had the lowest mean FNR (0.123), and plastic had the highest mean FNR (0.479). The LOD90 (?1 CFU detected 90% of the time) varied with surface material, from 0.015 CFU/cm2 on stainless steel up to 0.039 on plastic. It may be possible to improve sampling results by considering surface roughness in selecting sampling locations and interpreting spore recovery data. Further, FNR values (calculated as a function of concentration and surface material) can be used presampling to calculate the numbers of samples for statistical sampling plans with desired performance and postsampling to calculate the confidence in characterization and clearance decisions. PMID:22138998

  19. False-negative rate and recovery efficiency performance of a validated sponge wipe sampling method.

    PubMed

    Krauter, Paula A; Piepel, Greg F; Boucher, Raymond; Tezak, Matt; Amidan, Brett G; Einfeld, Wayne

    2012-02-01

    Recovery of spores from environmental surfaces varies due to sampling and analysis methods, spore size and characteristics, surface materials, and environmental conditions. Tests were performed to evaluate a new, validated sponge wipe method using Bacillus atrophaeus spores. Testing evaluated the effects of spore concentration and surface material on recovery efficiency (RE), false-negative rate (FNR), limit of detection (LOD), and their uncertainties. Ceramic tile and stainless steel had the highest mean RE values (48.9 and 48.1%, respectively). Faux leather, vinyl tile, and painted wood had mean RE values of 30.3, 25.6, and 25.5, respectively, while plastic had the lowest mean RE (9.8%). Results show roughly linear dependences of RE and FNR on surface roughness, with smoother surfaces resulting in higher mean REs and lower FNRs. REs were not influenced by the low spore concentrations tested (3.10 × 10(-3) to 1.86 CFU/cm(2)). Stainless steel had the lowest mean FNR (0.123), and plastic had the highest mean FNR (0.479). The LOD(90) (?1 CFU detected 90% of the time) varied with surface material, from 0.015 CFU/cm(2) on stainless steel up to 0.039 on plastic. It may be possible to improve sampling results by considering surface roughness in selecting sampling locations and interpreting spore recovery data. Further, FNR values (calculated as a function of concentration and surface material) can be used presampling to calculate the numbers of samples for statistical sampling plans with desired performance and postsampling to calculate the confidence in characterization and clearance decisions. PMID:22138998

  20. False-Negative Rate and Recovery Efficiency Performance of a Validated Sponge Wipe Sampling Method

    SciTech Connect

    Krauter, Paula; Piepel, Gregory F.; Boucher, Raymond; Tezak, Matthew S.; Amidan, Brett G.; Einfeld, Wayne

    2012-02-01

    Recovery of spores from environmental surfaces varies due to sampling and analysis methods, spore size and characteristics, surface materials, and environmental conditions. Tests were performed to evaluate a new, validated sponge wipe method using Bacillus atrophaeus spores. Testing evaluated the effects of spore concentration and surface material on recovery efficiency (RE), false-negative rate (FNR), limit of detection (LOD), and their uncertainties. Ceramic tile and stainless steel had the highest mean RE values (48.9 and 48.1%, respectively). Faux leather, vinyl tile, and painted wood had mean RE values of 30.3, 25.6, and 25.5, respectively, while plastic had the lowest mean RE (9.8%). Results show roughly linear dependences of RE and FNR on surface roughness, with smoother surfaces resulting in higher mean REs and lower FNRs. REs were not influenced by the low spore concentrations tested (3.10x10^-3 to 1.86 CFU/cm^2). Stainless steel had the lowest mean FNR (0.123), and plastic had the highest mean FNR (0.479). The LOD90 (>1 CFU detected 90% of the time) varied with surface material, from 0.015 CFU/cm^2 on stainless steel up to 0.039 on plastic. It may be possible to improve sampling results by considering surface roughness in selecting sampling locations and interpreting spore recovery data. Further, FNR values (calculated as a function of concentration and surface material) can be used presampling to calculate the numbers of samples for statistical sampling plans with desired performance and postsampling to calculate the confidence in characterization and clearance decisions.

  1. Lobular breast carcinoma: a case of rare possible 18F-FDG PET/CT and bone scan false negative.

    PubMed

    Maffione, Anna Margherita; Lisato, Laura Camilla; Rasi, Annalisa; Marzola, Maria Cristina; Colletti, Patrick M; Rubello, Domenico

    2015-02-01

    A patient with diffuse osteosclerotic bone metastases from invasive lobular breast carcinoma is presented with both F-FDG PET/CT and bone scans negative for hypermetabolic lesions. Skeletal metastases were documented by CT and bone marrow biopsy, and high increased CA 15-3 level was recorded. This case report points to the potential risk of false-negative FDG PET and bone scans examination in lobular carcinoma type. PMID:24999681

  2. False negative result for amphetamines on the Triage® Drug of Abuse panel?

    Microsoft Academic Search

    Wakako Hikiji; Keiko Kudo; Shinji Sato; Yosuke Usumoto; Akiko Tsuji; Noriaki Ikeda

    2009-01-01

    On-site drug screening devices are widely used today for their simple test procedures and instantaneous results. Among other\\u000a devices, a Triage® Drug of Abuse panel is considered to be highly reliable for its high specificity and sensitivity of abused\\u000a drugs. Although it is known that a false positive amphetamine (AMP) result may be obtained from the urine samples containing\\u000a putrefactive

  3. Differences in daptomycin and vancomycin ex vivo behaviour can lead to false interpretation of negative blood cultures.

    PubMed

    Grohs, P; Fantin, B; Lefort, A; Wolff, M; Gutmann, L; Mainardi, J-L

    2011-08-01

    In clinical studies on bacteraemia, the negativity of blood cultures is an important endpoint for comparing the efficacy of different therapeutic regimens. In FAN anaerobic blood culture medium (BacT/ALERT system), daptomycin displayed increased MIC against Staphylococcus aureus and improved abolishment of its carryover effect in charcoal when compared with vancomycin. Differences between these two drugs can lead to a false interpretation of negative blood cultures. To compare different antibiotic regimens for the treatment of bacteraemia, preliminary studies are mandatory to ensure that ex vivo antibiotic behaviour is similar in the blood-culture system used. PMID:21375652

  4. All That Glisters Is Not Gold: Sampling-Process Uncertainty in Disease-Vector Surveys with False-Negative and False-Positive Detections

    PubMed Central

    Abad-Franch, Fernando; Valença-Barbosa, Carolina; Sarquis, Otília; Lima, Marli M.

    2014-01-01

    Background Vector-borne diseases are major public health concerns worldwide. For many of them, vector control is still key to primary prevention, with control actions planned and evaluated using vector occurrence records. Yet vectors can be difficult to detect, and vector occurrence indices will be biased whenever spurious detection/non-detection records arise during surveys. Here, we investigate the process of Chagas disease vector detection, assessing the performance of the surveillance method used in most control programs – active triatomine-bug searches by trained health agents. Methodology/Principal Findings Control agents conducted triplicate vector searches in 414 man-made ecotopes of two rural localities. Ecotope-specific ‘detection histories’ (vectors or their traces detected or not in each individual search) were analyzed using ordinary methods that disregard detection failures and multiple detection-state site-occupancy models that accommodate false-negative and false-positive detections. Mean (±SE) vector-search sensitivity was ?0.283±0.057. Vector-detection odds increased as bug colonies grew denser, and were lower in houses than in most peridomestic structures, particularly woodpiles. False-positive detections (non-vector fecal streaks misidentified as signs of vector presence) occurred with probability ?0.011±0.008. The model-averaged estimate of infestation (44.5±6.4%) was ?2.4–3.9 times higher than naïve indices computed assuming perfect detection after single vector searches (11.4–18.8%); about 106–137 infestation foci went undetected during such standard searches. Conclusions/Significance We illustrate a relatively straightforward approach to addressing vector detection uncertainty under realistic field survey conditions. Standard vector searches had low sensitivity except in certain singular circumstances. Our findings suggest that many infestation foci may go undetected during routine surveys, especially when vector density is low. Undetected foci can cause control failures and induce bias in entomological indices; this may confound disease risk assessment and mislead program managers into flawed decision making. By helping correct bias in naïve indices, the approach we illustrate has potential to critically strengthen vector-borne disease control-surveillance systems. PMID:25233352

  5. Yale study finds false negative tests in breast cancer may lead to wrong drug choice:

    Cancer.gov

    A team of Yale Cancer Center researchers has confirmed that between 10-20% of breast cancers classified as Estrogen Receptor (ER) negative are really positive. Understanding when and why breast cancers may be misclassified has important implications for treatment and outcomes for women diagnosed with breast cancer.

  6. Hypothetical Explanations of the Negative Apparent Effects of Cloud Seeding in the Whitetop Experiment

    Microsoft Academic Search

    J. L. Lovasich; J. Neyman; E. L. Scott; M. A. Wells

    1971-01-01

    In order to explain the apparent losses of rain ascribable to seeding at the Whitetop trial, particularly large and highly significant in the stratum E (but not in the opposite stratum W) of experimental days, it has been hypothesized that seeding causes widespread cloudiness and subsequent lowering of ground temperatures. This hypothesis is flatly contradicted by the observations: the seeded

  7. Solubilized alphabeta Na,K-ATPase Remains Protomeric During Turnover Yet Shows Apparent Negative Cooperativity Toward ATP

    Microsoft Academic Search

    Douglas G. Ward; Jose D. Cavieres

    1993-01-01

    A prominent feature of the Na,K-ATPase reaction is an ATP dependence that suggests high- and low-affinity ATP requirements during the enzymic cycle. As only one ATP-binding domain has been identified in the alpha subunit and none has been identified in the beta subunit, it has seemed likely that the apparent negative cooperativity results from subunit interactions in an (alphabeta)_2 diprotomer.

  8. Apparent Culture-Negative Prosthetic Valve Endocarditis Caused by Peptostreptococcus magnus

    Microsoft Academic Search

    ERIC R. VAN DER VORM; ARJEN M. DONDORP; RUUD J. VAN KETEL; JACOB DANKERT

    2000-01-01

    In two patients with prosthetic valve endocarditis due to Peptostreptococcus magnus, blood cultures in the BacT\\/Alert and BACTEC 9240 systems were signal negative. The capability of the BacT\\/Alert system to detect various Peptostreptococcus species was assessed. P. magnus and P. anaerobius could not be detected, and sub- cultures remained negative. The growth in conventional media of these two species and

  9. Origin of Apparent Negative Heat Capacity in Constrained Microcanonical Modeling of Excited Nuclear Systems

    NASA Astrophysics Data System (ADS)

    Quinlan, Michael; Toke, Jan; Pawelczak, Iwona; Schröder, Wolf-Udo

    2007-10-01

    The origin of negative heat capacity in certain classes of microcanonical models of phase transitions in small systems is studied. It is demonstrated that the domain of negative heat capacity appears in such calculations as a result of an unphysical discontinuity in the model phase space and, specifically, the exclusion of energetically (microcanonically) allowed micro-states filling the space between the domains corresponding to different phases. It is also shown that already a crude filling of these unphysical gaps in the model phase space results in a restoration of the concavity of the entropic curve S(E*) and thus in an elimination of the faux negative heat capacity in the phase transition region.

  10. Molecular Studies Neglect Apparently Gram-Negative Populations in the Human Gut Microbiota

    PubMed Central

    Hugon, Perrine; Lagier, Jean-Christophe; Robert, Catherine; Lepolard, Catherine; Papazian, Laurent; Musso, Didier; Vialettes, Bernard

    2013-01-01

    Studying the relationships between gut microbiota, human health, and diseases is a major challenge that generates contradictory results. Most studies draw conclusions about the gut repertoire using a single biased metagenomics approach. We analyzed 16 different stool samples collected from healthy subjects who were from different areas, had metabolic disorders, were immunocompromised, or were treated with antibiotics at the time of the stool collection. The analyses performed included Gram staining, flow cytometry, transmission electron microscopy (TEM), quantitative real-time PCR (qPCR) of the Bacteroidetes and Firmicutes phyla, and pyrosequencing of the 16S rRNA gene amplicons targeting the V6 region. We quantified 1010 prokaryotes per gram of feces, which is less than was previously described. The Mann-Whitney test revealed that Gram-negative proportions of the prokaryotes obtained by Gram staining, TEM, and pyrosequencing differed according to the analysis used, with Gram-negative prokaryotes yielding median percentages of 70.6%, 31.0%, and 16.4%, respectively. A comparison of TEM and pyrosequencing analyses highlighted a difference of 14.6% in the identification of Gram-negative prokaryotes, and a Spearman test showed a tendency toward correlation, albeit not significant, in the Gram-negative/Gram-positive prokaryote ratio (? = 0.3282, P = 0.2146). In contrast, when comparing the qPCR and pyrosequencing results, a significant correlation was found for the Bacteroidetes/Firmicutes ratio (? = 0.6057, P = 0.0130). Our study showed that the entire diversity of the human gut microbiota remains unknown because different techniques generate extremely different results. We found that to assess the overall composition of bacterial communities, multiple techniques must be combined. The biases that exist for each technique may be useful in exploring the major discrepancies in molecular studies. PMID:23885002

  11. Detectability of the Eurasian otter by standard surveys: an approach using marking intensity to estimate false negative rates

    NASA Astrophysics Data System (ADS)

    Balestrieri, Alessandro; Remonti, Luigi; Prigioni, Claudio

    2011-01-01

    False negative detections may bias the surveys for rare species and reduce the reliability of models based on the proportion of occupied patches. We assessed the detectability of the Eurasian otter Lutra lutra through the standard survey method by analysing the detection history of 28 sampling stretches surveyed monthly between March 2001 and January 2003. Each survey negative for otter spraints was considered as a false negative if the otter had been recorded in the previous and/or following month (respectively, cFN and FN). Otter marking intensity (MI) (MI=N° of spraints per kilometre) was calculated and assumed to represent an index of its relative abundance. Spraints were found in 81.7% of all surveys. Yearly MI ranged from 1.02 to 101.4 spraints per kilometre. In 2002, mean MI was significantly lower than in the previous year, while no clear seasonal trend could be outlined. The minimum number of surveys required to establish the occurrence of the otter, as estimated by a probability model, was 2.6 and was inversely related to MI. For a sub-sample of 18 sampling stretches, the relation between the frequency of both cFN and FN and five variables of potential interest for otters was tested by means of stepwise linear multiple regressions, yielding two highly significant models, which both included only MI as the explanatory variable. The frequency of both FN and cFN was correlated to MI and the resulting equations used to assess the percentage of surveys positive for otters in both years. After the correction for non-detections, otter site occupancy did not vary between the 2 years, except for one river when applying the more conservative estimate of false negatives (cFN). Multiple visits and the assessing of MI should become standard components of otter surveys. This approach has broad applicability and may be applied to assess the large-scale distribution of other rare or elusive mammalian carnivores.

  12. Histologic Changes Associated With False-Negative Sentinel Lymph Nodes After Preoperative Chemotherapy in Patients With Confirmed Lymph Node-Positive Breast Cancer Before Treatment

    PubMed Central

    Brown, Alexandra S.; Hunt, Kelly K.; Shen, Jeannie; Huo, Lei; Babiera, Gildy V.; Ross, Merrick I.; Meric-Bernstam, Funda; Feig, Barry W.; Kuerer, Henry M.; Boughey, Judy C.; Ching, Christine D.; Gilcrease, Michael Z.

    2015-01-01

    BACKGROUND A wide range of false-negative rates has been reported for sentinel lymph node (SLN) biopsy after preoperative chemotherapy. The purpose of this study was to determine whether histologic findings in negative SLNs after preoperative chemotherapy are helpful in assessing the accuracy of SLN biopsy in patients with confirmed lymph node-positive disease before treatment. METHODS Eighty-six patients with confirmed lymph node-positive disease at presentation underwent successful SLN biopsy and axillary dissection after preoperative chemotherapy at a single institution between 1994 and 2007. Available hematoxylin and eosin-stained sections from patients with negative SLNs were reviewed, and associations between histologic findings in the negative SLNs and SLN status (true negative vs false negative) were evaluated. RESULTS Forty-seven (55%) patients had at least 1 positive SLN, and 39 (45%) patients had negative SLNs. The false-negative rate was 22%, and the negative predictive value was 67%. The negative SLNs from 17 of 34 patients with available slides had focal areas of fibrosis, some with associated foamy parenchymal histiocytes, fat necrosis, or calcification. These histologic findings occurred in 15 (65%) of 23 patients with true-negative SLNs and in only 2 (18%) of 11 patients with false-negative SLNs (P =.03, Fisher exact test, 2-tailed). The lack of these histologic changes had a sensitivity and specificity for identifying a false-negative SLN of 82% and 65%, respectively. CONCLUSIONS Absence of treatment effect in SLNs after chemotherapy in patients with lymph node-positive disease at initial presentation has good sensitivity but low specificity for identifying a false-negative SLN. PMID:20564394

  13. Solubilized alpha beta Na,K-ATPase remains protomeric during turnover yet shows apparent negative cooperativity toward ATP.

    PubMed

    Ward, D G; Cavieres, J D

    1993-06-01

    A prominent feature of the Na,K-ATPase reaction is an ATP dependence that suggests high- and low-affinity ATP requirements during the enzymic cycle. As only one ATP-binding domain has been identified in the alpha subunit and none has been identified in the beta subunit, it has seemed likely that the apparent negative cooperativity results from subunit interactions in an (alpha beta)2 diprotomer. To test this possibility, we have examined the behavior of solubilized alpha beta protomers of Na,K-ATPase down to 50 nM [gamma-32P]ATP. Active-enzyme analytical ultracentrifugation shows that the protomer is the active species and that no oligomerization occurs during turnover. However, we find that dual ATP effects can be clearly demonstrated and that nonhydrolyzable ATP analogs can stimulate the Na,K-ATPase activity of the soluble protomer. We conclude that the apparent negative cooperativity is inherent to the alpha beta protomer and that this should explain some of the complexities found with membrane-bound Na,K-ATPase and, perhaps, other P-type cation pumps. PMID:8389481

  14. Residual Antibiotics in Decontaminated Human Cardiovascular Tissues Intended for Transplantation and Risk of Falsely Negative Microbiological Analyses

    PubMed Central

    Gatto, Claudio; Manara, Sabrina; Dainese, Luca; Polvani, Gianluca; Tóthová, Jana D'Amato

    2014-01-01

    We investigated the presence of antibiotics in cryopreserved cardiovascular tissues and cryopreservation media, after tissue decontamination with antibiotic cocktails, and the impact of antibiotic residues on standard tissue bank microbiological analyses. Sixteen cardiovascular tissues were decontaminated with bank-prepared cocktails and cryopreserved by two different tissue banks according to their standard operating procedures. Before and after decontamination, samples underwent microbiological analysis by standard tissue bank methods. Cryopreserved samples were tested again with and without the removal of antibiotic residues using a RESEP tube, after thawing. Presence of antibiotics in tissue homogenates and processing liquids was determined by a modified agar diffusion test. All cryopreserved tissue homogenates and cryopreservation media induced important inhibition zones on both Staphylococcus aureus- and Pseudomonas aeruginosa-seeded plates, immediately after thawing and at the end of the sterility test. The RESEP tube treatment markedly reduced or totally eliminated the antimicrobial activity of tested tissues and media. Based on standard tissue bank analysis, 50% of tissues were found positive for bacteria and/or fungi, before decontamination and 2 out of 16 tested samples (13%) still contained microorganisms after decontamination. After thawing, none of the 16 cryopreserved samples resulted positive with direct inoculum method. When the same samples were tested after removal of antibiotic residues, 8 out of 16 (50%) were contaminated. Antibiotic residues present in tissue allografts and processing liquids after decontamination may mask microbial contamination during microbiological analysis performed with standard tissue bank methods, thus resulting in false negatives. PMID:25397402

  15. False negative rate and other performance measures of a sponge-wipe surface sampling method for low contaminant concentrations.

    SciTech Connect

    Einfeld, Wayne; Krauter, Paula A.; Boucher, Raymond M.; Tezak, Mathew; Amidan, Brett G. (Pacific Northwest National Laboratory, Richland, WA); Piepel, Greg F. (Pacific Northwest National Laboratory, Richland, WA)

    2011-05-01

    Recovery of spores from environmental surfaces is known to vary due to sampling methodology, techniques, spore size and characteristics, surface materials, and environmental conditions. A series of tests were performed to evaluate a new, validated sponge-wipe method. Specific factors evaluated were the effects of contaminant concentrations and surface materials on recovery efficiency (RE), false negative rate (FNR), limit of detection (LOD) - and the uncertainties of these quantities. Ceramic tile and stainless steel had the highest mean RE values (48.9 and 48.1%, respectively). Faux leather, vinyl tile, and painted wood had mean RE values of 30.3, 25.6, and 25.5, respectively, while plastic had the lowest mean RE (9.8%). Results show a roughly linear dependence of surface roughness on RE, where the smoothest surfaces have the highest mean RE values. REs were not influenced by the low spore concentrations tested (3 x 10{sup -3} to 1.86 CFU/cm{sup 2}). The FNR data were consistent with RE data, showing a trend of smoother surfaces resulting in higher REs and lower FNRs. Stainless steel generally had the lowest mean FNR (0.123) and plastic had the highest mean FNR (0.479). The LOD{sub 90} varied with surface material, from 0.015 CFU/cm{sup 2} on stainless steel up to 0.039 on plastic. Selecting sampling locations on the basis of surface roughness and using roughness to interpret spore recovery data can improve sampling. Further, FNR values, calculated as a function of concentration and surface material, can be used pre-sampling to calculate the numbers of samples for statistical sampling plans with desired performance, and post-sampling to calculate the confidence in characterization and clearance decisions.

  16. Effects of Maternal Negativity and of Early and Recent Recurrent Depressive Disorder on Children's False Belief Understanding

    ERIC Educational Resources Information Center

    Rohrer, Lisa M.; Cicchetti, Dante; Rogosch, Fred A.; Toth, Sheree L.; Maughan, Angeline

    2011-01-01

    Research has shown that children of depressed mothers are at risk for problems in a variety of developmental domains; however, little is known about the effects of maternal depression on children's emerging understanding of false beliefs. In this study, 3 false belief tasks were administered to 5-year-old children whose mothers had either met…

  17. Factors affecting failed localisation and false-negative rates of sentinel node biopsy in breast cancer – results of the ALMANAC validation phase

    Microsoft Academic Search

    Amit Goyal; Robert G Newcombe; Alok Chhabra; Robert E Mansel

    2006-01-01

    SummaryBackground  Despite the widespread application of sentinel lymph node biopsy (SLNB) for early stage breast cancer, there is a wide variation in reported test performance characteristics. A major aim of this prospective multicentre validation study was to quantify detection and false-negative rates of SLNB and evaluate factors influencing them.Methods  Eight-hundred and fourty-two patients with clinically node-negative breast cancer underwent SLNB according to

  18. False Negatives in Sexual Abuse Disclosure InterviewsIncidence and Influence of Caretaker's Belief in Abuse in Cases of Accidental Abuse Discovery by Diagnosis of STD

    Microsoft Academic Search

    LOUANNE LAWSON; MARK CHAFFIN

    1992-01-01

    Verbal disclosure of abuse in a specialized interview was studied in a sample of 28 children, ages 3 to menarche, who presented with purely physical complaints later diagnosed as a sexually transmitted disease, in the absence of any known prior disclosure or suspicion of sexual abuse. Only 43% gave any verbal confirmation of sexual contact. Fifty-seven percent were “false negatives.”

  19. JC Virus PCR Detection Is Not Infallible: A Fulminant Case of Progressive Multifocal Leukoencephalopathy with False-Negative Cerebrospinal Fluid Studies despite Progressive Clinical Course and Radiological Findings

    PubMed Central

    Babi, Mohamed-Ali; Pendlebury, William; Braff, Steven; Waheed, Waqar

    2015-01-01

    We describe a case with a false-negative PCR-based analysis for JC virus in cerebrospinal fluid (CSF) in a patient with clinical and radiological findings suggestive of progressive multifocal leukoencephalopathy (PML) who was on chronic immunosuppressive therapy for rheumatoid arthritis. Our patient developed rapidly progressive global decline with clinical and radiographic findings suggestive of PML, but JC virus PCR in CSF was negative. The patient passed away 3 months from the onset of her neurological symptoms. Autopsy confirmed the diagnosis of PML with presence of JC-polyoma virus by immunohistochemical staining. This case highlights the potential of false-negative JC virus PCR in CSF when radiographic and clinical features are suggestive of “possible PML.” We review the plausible causes of potential false-negative CSF results and suggest that when the clinical presentation is suspicious for PML repeat CSF analysis utilizing ultrasensitive PCR assay and subsequent brain biopsy should be considered if CSF remains negative. Additionally, appropriate exclusion of other neurologic conditions is essential.

  20. Experimental Design for a Macrofoam-Swab Study Relating the Recovery Efficiency and False Negative Rate to Low Concentrations of Two Bacillus anthracis Surrogates on Four Surface Materials

    SciTech Connect

    Piepel, Gregory F.; Hutchison, Janine R.

    2014-12-05

    This report describes the experimental design for a laboratory study to quantify the recovery efficiencies and false negative rates of a validated, macrofoam-swab sampling method for low concentrations of Bacillus anthracis Sterne (BAS) and Bacillus atrophaeus (BG) spores on four surface materials (stainless steel, glass, vinyl tile, plastic light cover panel). Two analytical methods (culture and polymerase chain reaction) will be used. Only one previous study has investigated how the false negative rate depends on test factors. The surrogates BAS and BG have not been tested together in the same study previously. Hence, this study will provide for completing gaps in the available information on the performance of macrofoam-swab sampling at low concentrations.

  1. Experimental Design for a Macrofoam Swab Study Relating the Recovery Efficiency and False Negative Rate to Low Concentrations of Two Bacillus anthracis Surrogates on Four Surface Materials

    SciTech Connect

    Piepel, Gregory F.; Hutchison, Janine R.

    2014-04-16

    This report describes the experimental design for a laboratory study to quantify the recovery efficiencies and false negative rates of a validated, macrofoam swab sampling method for low concentrations of Bacillus anthracis Sterne (BAS) and Bacillus atrophaeus (BG) spores on four surface materials (stainless steel, glass, vinyl tile, plastic light cover panel). Two analytical methods (plating/counting and polymerase chain reaction) will be used. Only one previous study has investigated false negative as a function of affecting test factors. The surrogates BAS and BG have not been tested together in the same study previously. Hence, this study will provide for completing gaps in the available information on the performance of macrofoam swab sampling at low concentrations.

  2. Census and analysis of persistent false-negative results in serological diagnosis of human immunodeficiency virus type 1 group O infections.

    PubMed

    Plantier, J-C; Djemai, M; Lemée, V; Reggiani, A; Leoz, M; Burc, L; Vessière, A; Rousset, D; Poveda, J-D; Henquell, C; Gautheret-Dejean, A; Barin, F

    2009-09-01

    Human immunodeficiency viruses (HIV) have a high level of genetic diversity. The outlier variants of HIV type 1 (HIV-1) group O are distantly related to HIV-1 group M. Their divergence has an impact on serological diagnosis, with a risk of false-negative results. In this study, we report 20 failure cases, involving patients with primary or chronic infection, in France and Cameroon between 2001 and 2008. Our results indicate that some assays detected group O infection much less efficiently than others. Two major reasons for these false-negative results were identified: the presence or absence of a group O-specific antigen (and the designed sequence) for the detection of antibodies and the greater envelope variability of group O than of group M strains. This study highlights the complexity of screening for these divergent variants and the need to evaluate test performance with a large panel of strains, due to the extensive diversity of group O variants. PMID:19625478

  3. Census and Analysis of Persistent False-Negative Results in Serological Diagnosis of Human Immunodeficiency Virus Type 1 Group O Infections?

    PubMed Central

    Plantier, J.-C.; Djemai, M.; Lemée, V.; Reggiani, A.; Leoz, M.; Burc, L.; Vessière, A.; Rousset, D.; Poveda, J.-D.; Henquell, C.; Gautheret-Dejean, A.; Barin, F.

    2009-01-01

    Human immunodeficiency viruses (HIV) have a high level of genetic diversity. The outlier variants of HIV type 1 (HIV-1) group O are distantly related to HIV-1 group M. Their divergence has an impact on serological diagnosis, with a risk of false-negative results. In this study, we report 20 failure cases, involving patients with primary or chronic infection, in France and Cameroon between 2001 and 2008. Our results indicate that some assays detected group O infection much less efficiently than others. Two major reasons for these false-negative results were identified: the presence or absence of a group O-specific antigen (and the designed sequence) for the detection of antibodies and the greater envelope variability of group O than of group M strains. This study highlights the complexity of screening for these divergent variants and the need to evaluate test performance with a large panel of strains, due to the extensive diversity of group O variants. PMID:19625478

  4. Adenocarcinoma with BAC Features Presented as the Nonsolid Nodule Is Prone to Be False-Negative on 18F-FDG PET/CT

    PubMed Central

    Wu, Hu-bing; Wang, Lijuan; Wang, Quan-shi; Han, Yan-jian; Li, Hong-sheng; Zhou, Wen-lan; Tian, Ying

    2015-01-01

    Purpose. The present study investigated which type of adenocarcinoma with BAC features was prone to be false-negative on 18F-FDG PET/CT. Materials and Methods. A retrospective study was performed on 51 consecutive patients with localized adenocarcinoma with BAC features. CT and PET were assessed for lesion size, GGO percentage, and SUVmax. Lesions with FDG uptake the same as or more than mediastinal blood-pool activity were considered as PET-positive. Results. Of the 51 cases, 19.6% presented as pure GGO nodules, 31.4% as mixed nodules, and 49.0% as solid nodules. None of the pure GGO nodules was 18F-FDG avid, compared with 37.5% of mixed nodules and 96.0% of solid nodules (?2 = 31.55, P = 0.000). In the mixed nodule group, SUVmax was negatively correlated with GGO percentage (r = ?0.588; P = 0.021). The positive detection rate of 18F-FDG PET/CT was 50.0%, 55.6%, and 100% in tumors 1.1–2.0?cm, 2.1–3.0?cm, and >3.0?cm in diameter, respectively (?2 = 5.815, P = 0.055). General linear model factor analysis showed that the GGO was an important factor contributing to false-negative PET/CT results (F = 23.992, P = 0.000), but lesion size was not (F = 0.602, P = 0.866). Conclusions. The present study indicated that the adenocarcinoma with BAC features presented as nonsolid nodule is prone to be false negative on 18F-FDG PET/CT. PMID:25879020

  5. Impact of age on the false negative rate of human papillomavirus DNA test in patients with atypical squamous cells of undetermined significance

    PubMed Central

    Won, Kyu-Hee; Lee, Jae Yeon; Cho, Hye-Yon; Suh, Dong Hoon; No, Jae Hong

    2015-01-01

    Objective Human papillomavirus (HPV) test was incorporated into the triage of lesser abnormal cervical cytologies: atypical squamous cells of undetermined significance (ASCUS) or low-grade squamous intraepithelial lesion (LSIL). This study aimed to evaluate the impact of age on the efficacy of HPV testing in patients with lesser abnormal cervical cytologies. Methods A total of 439 patients with ASCUS or LSIL were included. The association between age groups and the diagnostic performances of HPV test for high-grade cervical intraepithelial neoplasia (CIN2+) was evaluated. Results Median age was 44 years (range, 17 to 75 years). ASCUS was more frequently observed in older patients while LSIL was more common in younger patients (P=0.002). CIN2+ was found in 11.3% (32/284) of the ASCUS patients and 12.9% (20/155) of patients with LSIL. Older patients with ASCUS showed lower HPV infection rates (P=0.025), but not LSIL (P=0.114). However, the prevalence of CIN2+ was similar between the age groups with ASCUS or LSIL. In patients with ASCUS, the false negative rate of HPV test for CIN2+ was 6.2%. The false negative rate of the HPV test became higher with increasing of the age after the age of 50 (P=0.034). Conclusion Our findings suggest that false negative rate of the HPV test for CIN2+ in ASCUS patients older than 50 years might become higher with increasing of the age. Negative HPV results in patients of the age >50 years with ASCUS should be carefully interpreted. PMID:25798425

  6. False-negative dengue cases in Roraima, Brazil: an approach regarding the high number of negative results by NS1 ag kits.

    PubMed

    Acosta, Pablo O A; Granja, Fabiana; Meneses, Cátia A; Nascimento, Ismael A S; Sousa, Débora D; Lima Júnior, Wilson P; Naveca, Felipe Gomes

    2014-01-01

    Serum samples from 150 NS1-negative (Platelia ELISA) patients presumptively diagnosed with dengue were analyzed by the TaqMan probed real-time reverse transcription PCR (TaqMan qRT-PCR) method. The qRT-PCR positive samples were tested for serotype by semi-nested RT-PCR and a qualitative immunochromatographic assay for IgG and IgM. Molecular detection methods showed 33 (22%) positive samples out of 150 NS1-antigen negative samples. Of these, 72% were collected up to day 2 after the onset of symptoms, when diagnostic sensitivity of NS1-antigen test assays is significantly enhanced. Most of the cases were not characterized as secondary infection. Twenty-eight samples were successfully serotyped, 75% of which for DENV-4, 14% for DENV-2, 7% for DENV-3 and 4% for DENV-1. These findings reaffirm the hyperendemic situation of the state of Roraima and suggest a lower sensitivity of the NS1 test, mainly when DENV-4 is the predominant serotype. Health care providers should therefore be aware of samples tested negative by NS1 antigen assays, especially when clinical symptoms and other laboratory data results show evidence of dengue infection. PMID:25229228

  7. FALSE-NEGATIVE DENGUE CASES IN RORAIMA, BRAZIL: AN APPROACH REGARDING THE HIGH NUMBER OF NEGATIVE RESULTS BY NS1 AG KITS

    PubMed Central

    Acosta, Pablo O. A.; Granja, Fabiana; Meneses, Cátia A.; Nascimento, Ismael A. S.; Sousa, Débora D.; Lima, Wilson P.; Naveca, Felipe Gomes

    2014-01-01

    Serum samples from 150 NS1-negative (Platelia ELISA) patients presumptively diagnosed with dengue were analyzed by the TaqMan probed real-time reverse transcription PCR (TaqMan qRT-PCR) method. The qRT-PCR positive samples were tested for serotype by semi-nested RT-PCR and a qualitative immunochromatographic assay for IgG and IgM. Molecular detection methods showed 33 (22%) positive samples out of 150 NS1-antigen negative samples. Of these, 72% were collected up to day 2 after the onset of symptoms, when diagnostic sensitivity of NS1-antigen test assays is significantly enhanced. Most of the cases were not characterized as secondary infection. Twenty-eight samples were successfully serotyped, 75% of which for DENV-4, 14% for DENV-2, 7% for DENV-3 and 4% for DENV-1. These findings reaffirm the hyperendemic situation of the state of Roraima and suggest a lower sensitivity of the NS1 test, mainly when DENV-4 is the predominant serotype. Health care providers should therefore be aware of samples tested negative by NS1 antigen assays, especially when clinical symptoms and other laboratory data results show evidence of dengue infection. PMID:25229228

  8. False-negative ultrasound-guided vacuum-assisted biopsy of the breast: difference with US-detected and MRI-detected lesions

    Microsoft Academic Search

    Naomi Sakamoto; Mitsuhiro Tozaki; Kuniki Higa; Satoko Abe; Shinji Ozaki; Eisuke Fukuma

    2010-01-01

    Background  The purpose of this study was to retrospectively examine the frequency and causes of a false-negative result of ultrasound\\u000a (US)-guided vacuum-assisted biopsy.\\u000a \\u000a \\u000a \\u000a \\u000a Methods  A retrospective review was performed of 835 patients with 986 consecutive lesions who had undergone US-guided vacuum-assisted\\u000a biopsy (US-VAB) using 11-gauge probes. We divided the lesions into two groups (US-detected and MRI-detected lesions). The\\u000a sizes of the lesions

  9. Detection of human cytomegalovirus DNA in paraffin sections of human brain by polymerase chain reaction and the occurrence of false negative results.

    PubMed Central

    Gass, P; Kiessling, M; Schäfer, P; Mester, C; Schmitt, H P; Kühn, J E

    1993-01-01

    Paraffin-embedded necropsy material from 6 patients with human cytomegalovirus encephalitis (HCMVE) corroborated by immunocytochemistry and 11 control cases were examined for the presence of human cytomegalovirus (HCMV) DNA by a nested polymerase chain reaction (nPCR). A characteristic 183 base pair (bp) fragment of the HCMV genome could readily be amplified in 4 cases of HCMVE. In 2 cases of HCMVE, viral DNA could be demonstrated only sporadically by PCR, due most likely to inefficient DNA extraction or DNA degradation. All control cases remained negative. The nPCR provides a specific method for detecting HCMV DNA in routinely processed biopsy and necropsy material and may be used in archival tissues for the diagnosis of infection. Fixation of samples and DNA extraction are, however, crucial steps and require careful control if PCR is used for detection of HCMV, to avoid false negative results. Images PMID:8382271

  10. Are apparent negative effects of feeding GM MON810 maize to Atlantic salmon, Salmo salar, caused by confounding factors?

    PubMed

    Sissener, Nini H; Hemre, Gro-Ingunn; Lall, Santosh P; Sagstad, Anita; Petersen, Kjell; Williams, Jason; Rohloff, Jens; Sanden, Monica

    2011-07-01

    The present study was conducted to follow up on apparent differences in growth, relative organ sizes, cellular stress and immune function in Atlantic salmon fed feed containing GM Bacillus thuringiensis maize compared with feed containing the non-modified parental maize line. Gene expression profiling on the distal intestinal segment and liver was performed by microarray, and selected genes were followed up by quantitative PCR (qPCR). In the liver, qPCR revealed some differentially regulated genes, including up-regulation of gelsolin precursor, down-regulation of ferritin heavy subunit and a tendency towards down-regulation of metallothionein (MT)-B. This, combined with the up-regulation of anti-apoptotic protein NR13 and similar tendencies for ferritin heavy chain and MT-A and -B in the distal intestine, suggests changes in cellular stress/antioxidant status. This corresponds well with and strengthens previous findings in these fish. To exclude possible confounding factors, the maize ingredients were analysed for mycotoxins and metabolites. The GM maize contained 90 ?g/kg of deoxynivalenol (DON), while the non-GM maize was below the detection limit. Differences were also observed in the metabolite profiles of the two maize varieties, some of which seemed connected to the mycotoxin level. The effects on salmon observed in the present and previous studies correspond relatively well with the effects of DON as reported in the literature for other production animals, but knowledge regarding effects and harmful dose levels in fish is scarce. Thus, it is difficult to conclude whether the observed effects are caused by the DON level or by some other aspect of the GM maize ingredient. PMID:21418706

  11. Control of bovine virus diarrhoea at the herd level: reducing the risk of false negatives in the detection of persistently infected cattle.

    PubMed

    Laureyns, Jozef; Ribbens, Stefaan; de Kruif, Aart

    2010-04-01

    The need to detect and eliminate cattle persistently infected (PI) with bovine viral diarrhoea virus (BVDV) is key to the control of BVD and has been shown to be very effective in eradicating BVDV from infected herds. However, because of pitfalls in the detection procedures, some PI animals can be missed and, as a result, are not identified and removal is delayed. The high prevalence of BVDV in cattle populations in some countries (such as Belgium and neighbouring countries) means there is a high risk of reinfection of a herd from which BVDV has been eradicated. Based on both practical experience and a literature study, this review considers those points that are critical to minimising the number of false negatives in the detection of PI cattle. PMID:19157928

  12. The use of core needle biopsy as first-line in diagnosis of thyroid nodules reduces false negative and inconclusive data reported by fine-needle aspiration

    PubMed Central

    2014-01-01

    Background The reported reliability of core needle biopsy (CNB) is high in assessing thyroid nodules after inconclusive fine-needle aspiration (FNA) attempts. However, first-line use of CNB for nodules considered at risk by ultrasonography (US) has yet to be studied. The aim of this study were: 1) to evaluate the potential merit of using CNB first-line instead of conventional FNA in thyroid nodules with suspicious ultrasonographic features; 2) to compare CNB and FNA as a first-line diagnostic procedure in thyroid lesions at higher risk of cancer. Methods Seventy-seven patients with a suspicious-appearing, recently discovered solid thyroid nodule were initially enrolled as study participants. No patients had undergone prior thyroid fine-needle aspiration/biopsy. Based on study design, all patients were proposed to undergo CNB as first-line diagnostic aspiration, while those patients refusing to do so underwent conventional FNA. Results Five patients refused the study, and a total of 31 and 41 thyroid nodules were subjected to CNB and FNA, respectively. At follow-up, the overall rate of malignancy was of 80% (CNB, 77%; FNA, 83%). However, the diagnostic accuracy of CNB (97%) was significantly (P?false negative (N?=?1), indeterminate (N?=?2) or not adequate (N?=?1) samples. Conclusions CNB can reduce the false negative and inconclusive results of conventional FNA and should be considered a first-line method in assessing solid thyroid nodules at high risk of malignancy. PMID:24661377

  13. An MTANN CAD for detection of polyps in false-negative CT colonography cases in a large multicenter clinical trial: preliminary results

    NASA Astrophysics Data System (ADS)

    Suzuki, Kenji; Sheu, Ivan; Epstein, Mark; Kohlbrenner, Ryan; Lostumbo, Antonella; Rockey, Don C.; Dachman, Abraham H.

    2008-03-01

    A major challenge in computer-aided detection (CAD) of polyps in CT colonography (CTC) is the detection of "difficult" polyps which radiologists are likely to miss. Our purpose was to develop a CAD scheme incorporating massive-training artificial neural networks (MTANNs) and to evaluate its performance on false-negative (FN) cases in a large multicenter clinical trial. We developed an initial polyp-detection scheme consisting of colon segmentation based on CT value-based analysis, detection of polyp candidates based on morphologic analysis, and quadratic discriminant analysis based on 3D pattern features for classification. For reduction of false-positive (FP) detections, we developed multiple expert 3D MTANNs designed to differentiate between polyps and seven types of non-polyps. Our independent database was obtained from CTC scans of 155 patients with polyps from a multicenter trial in which 15 medical institutions participated nationwide. Among them, about 45% patients received FN interpretations in CTC. For testing our CAD, 14 cases with 14 polyps/masses were randomly selected from the FN cases. Lesion sizes ranged from 6-35 mm, with an average of 10 mm. The initial CAD scheme detected 71.4% (10/14) of "missed" polyps, including sessile polyps and polyps on folds, with 18.9 (264/14) FPs per case. The MTANNs removed 75% (197/264) of the FPs without loss of any true positives; thus, the performance of our CAD scheme was improved to 4.8 (67/14) FPs per case. With our CAD scheme incorporating MTANNs, 71.4% of polyps "missed" by radiologists in the trial were detected correctly, with a reasonable number of FPs.

  14. Experimental Design for a Sponge-Wipe Study to Relate the Recovery Efficiency and False Negative Rate to the Concentration of a Bacillus anthracis Surrogate for Six Surface Materials

    Microsoft Academic Search

    Gregory F. Piepel; Brett G. Amidan; Paula Krauter; Wayne Einfeld

    2011-01-01

    Two concerns were raised by the Government Accountability Office following the 2001 building contaminations via letters containing Bacillus anthracis (BA). These included the: 1) lack of validated sampling methods, and 2) need to use statistical sampling to quantify the confidence of no contamination when all samples have negative results. Critical to addressing these concerns is quantifying the false negative rate

  15. SYBR Green-Based Real-Time Quantitative PCR Assay for Detection of West Nile Virus Circumvents False-Negative Results Due to Strain Variability

    PubMed Central

    Papin, James F.; Vahrson, Wolfgang; Dittmer, Dirk P.

    2004-01-01

    Real-time quantitative PCR is used routinely for the high-throughput diagnosis of viral pathogens, such as West Nile virus (WNV). Rapidly evolving RNA viruses present a challenge for diagnosis because they accumulate mutations that may render them undetectable. To explore the effect of sequence variations on assay performance, we generated every possible single point mutation within the target region of the widely used TaqMan assay for WNV and found that the TaqMan assay failed to detect 47% of possible single nucleotide variations in the probe-binding site and was unable to detect any targets with more than two mutations. In response, we developed and validated a less expensive assay with the intercalating dye SYBR green. The SYBR green-based assay was as sensitive as the TaqMan assay for WNV. Importantly, it detected 100% of possible WNV target region variants. The assay developed here adds an additional layer of protection to guard against false-negative results that result from natural variations or drug-directed selection and provides a rapid means to identify such variants for subsequent detailed analysis. PMID:15070997

  16. Angina Relief by Ranolazine Identifies False-Negative SPECT Myocardial Perfusion Scans in Patients with Coronary Disease Demonstrated by Coronary Angiography.

    PubMed

    Murray, Gary L

    2014-09-01

    Normal myocardial perfusion imaging (MPI) reduces intermediate- or high-risk pretest probability patients to low- or intermediate-risk posttest probability, respectively, for coronary disease (CD). Since ranolazine (RAN) relieves only angina, anginal patients with normal MPI whose angina is relieved by RAN present a significant dilemma. The purpose of this retrospective chart review was to confirm the impression that coronary angiography (CA) is indicated in patients whose class 3 to 4 angina is relieved by RAN, but have normal myocardial single-photon emission computed tomography (SPECT) MPIs. Charts of patients with stable class 3 to 4 angina (typical and atypical) and normal MPIs (left ventricular ejection fraction [LVEF] ?50% and segmental score?=?0) were reviewed. CA was done on all the patients with complete angina relief taking RAN, as well as nonresponders whose anginal etiology could not be explained. Stenoses were considered flow-restrictive when more than 70% diameter stenosis is observed by quantitative CA, or, when 50 to 70%, fractional flow reserve (FFR) measured ?0.80. RAN relieved angina in 36 of 54 (67%) patients. Of the known cases, 25 of these 36 (69%) had 43 stenoses ?50% (mean?=?66%): 15 (60%) had 1 vessel disease; 9 (36%) had multivessel disease; 18 (72%) had left anterior descending (LAD) disease; 1 (4%) had left main disease. Twenty one of 43 (49%) stenosis were?>?70%; 22 (51%) stenoses were 50 to 70% and required FFR measurement. Twenty nine of 43 stenoses (67%) were considered flow-restrictive in 18 of these 25 (72%) patients. Eight RAN nonresponders with no explanation for angina had no CD at CA. RAN angina relief is invaluable in identifying falsely negative SPECT MPI, and 50% of these patients have flow-restrictive stenoses. PMID:25317027

  17. Possible false-negative results on therapeutic drug monitoring of phenytoin using a particle enhanced turbidimetric inhibition immunoassay in a patient with a high level of IgM.

    PubMed

    Hirata, Kenshiro; Saruwatari, Junji; Enoki, Yuhuki; Iwata, Kazufumi; Urata, Yukino; Aizawa, Keiji; Ueda, Kentaro; Shirouzono, Takumi; Imamura, Motoki; Moriuchi, Hiroshi; Ishima, Yu; Kadowaki, Daisuke; Watanabe, Hiroshi; Hirata, Sumio; Maruyama, Toru; Fukunaga, Eiko

    2014-10-01

    : In this report, the authors described the unusual case of a patient in whom the plasma phenytoin concentration was unexpectedly not detected on a particle-enhanced turbidimetric inhibition immunoassay (PETINIA) technique, a typical immunoassay for phenytoin. The plasma concentration was measured using PETINIA and high-performance liquid chromatography in a 69-year-old male patient treated with fosphenytoin intravenously at the standard dose for 7 days. Although the plasma concentration of phenytoin was below the limit of detection (<0.5 mcg/mL) on PETINIA after the administration of fosphenytoin, the trough plasma concentration was estimated to be between 5 and 10 mg/L on high-performance liquid chromatography. When the plasma concentrations of IgM and IgG were measured using an enzyme-linked immunosorbent assay, the plasma IgG level was within the reference range, whereas the plasma IgM level was 2-3 times higher than the upper limit of the reference range. We concluded that the PETINIA method yielded a possible false-negative result regarding the phenytoin level in this patient, perhaps because of some hindrance to the measurement process by IgM. This case suggests that false-negative results should be considered when therapeutic drug monitoring reveals abnormally low values using PETINIA and that it is necessary to evaluate the plasma IgM level. PMID:24632808

  18. MSPI False Indication Probability Simulations

    SciTech Connect

    Dana Kelly; Kurt Vedros; Robert Youngblood

    2011-03-01

    This paper examines false indication probabilities in the context of the Mitigating System Performance Index (MSPI), in order to investigate the pros and cons of different approaches to resolving two coupled issues: (1) sensitivity to the prior distribution used in calculating the Bayesian-corrected unreliability contribution to the MSPI, and (2) whether (in a particular plant configuration) to model the fuel oil transfer pump (FOTP) as a separate component, or integrally to its emergency diesel generator (EDG). False indication probabilities were calculated for the following situations: (1) all component reliability parameters at their baseline values, so that the true indication is green, meaning that an indication of white or above would be false positive; (2) one or more components degraded to the extent that the true indication would be (mid) white, and “false” would be green (negative) or yellow (negative) or red (negative). In key respects, this was the approach taken in NUREG-1753. The prior distributions examined were the constrained noninformative (CNI) prior used currently by the MSPI, a mixture of conjugate priors, the Jeffreys noninformative prior, a nonconjugate log(istic)-normal prior, and the minimally informative prior investigated in (Kelly et al., 2010). The mid-white performance state was set at ?CDF = ?10 ? 10-6/yr. For each simulated time history, a check is made of whether the calculated ?CDF is above or below 10-6/yr. If the parameters were at their baseline values, and ?CDF > 10-6/yr, this is counted as a false positive. Conversely, if one or all of the parameters are set to values corresponding to ?CDF > 10-6/yr but that time history’s ?CDF < 10-6/yr, this is counted as a false negative indication. The false indication (positive or negative) probability is then estimated as the number of false positive or negative counts divided by the number of time histories (100,000). Results are presented for a set of base case parameter values, and three sensitivity cases in which the number of FOTP demands was reduced, along with the Birnbaum importance of the FOTP.

  19. Apparent absence of negative feedback in middle-aged persistent-estrous rats following luteinizing hormone-releasing hormone agonist treatment: relation to plasma inhibin and 17 beta-estradiol.

    PubMed

    Matt, D W; Dahl, K D; Sarkissian, A; Sayles, T E

    1993-02-01

    Reproductive aging in female rats is associated with a transition from regular estrous cyclicity to an anovulatory condition described as persistent estrous (PE). This PE condition is characterized by continued follicular development with elevated circulating levels of estrogen and FSH. In an attempt to investigate further the age-related changes in neuroendocrine function of PE rats, we have developed a model through which the return of hypothalamic-pituitary and ovarian function can be assessed following the withdrawal of chronic LHRH agonist suppression. Subsequent to withdrawal of continuous (2.5 micrograms/h for 12 days) LHRH agonist [DTrp6, Pro9-NHEt]-LHRH (LHRH-AG) treatment, circulating FSH concentrations in PE rats increase and remain elevated with an apparent absence of ovarian negative feedback, and these rats fail to return to estrous cyclicity. In the present studies, estrogen administration induced significant decreases in FSH secretion in PE rats following withdrawal of LHRH-AG treatment and ovariectomy (OVX), suggesting that the negative feedback response to estrogen is maintained in PE females. However, progesterone administration 2 days later failed to elicit a positive feedback response of gonadotropin secretion in PE females prior to LHRH-AG treatment, serum inhibin and 17 beta-estradiol (E2) concentrations were similar in middle-aged PE rats and young cyclic females on proestrus, while FSH levels were significantly greater in PE rats. After withdrawal of LHRH-AG treatment, plasma FSH concentrations remained elevated in PE rats as compared to young rats despite similar increases in E2. However, increases in plasma inhibin were delayed and significantly attenuated in PE rats.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:8439622

  20. Lying and falsely implicating

    Microsoft Academic Search

    Jörg Meibauer

    2005-01-01

    This paper analyses falsely implicating from the point of view of Gricean theory of implicature, focusing on the Story of the Mate and the Captain which is a classical example of lying while saying the truth. It is argued that the case of falsely implicating should be included within a general definition of lying. Whether Particularised Conversational Implicatures (PCI), as

  1. Experimental Design for a Sponge-Wipe Study to Relate the Recovery Efficiency and False Negative Rate to the Concentration of a Bacillus anthracis Surrogate for Six Surface Materials

    SciTech Connect

    Piepel, Gregory F.; Amidan, Brett G.; Krauter, Paula; Einfeld, Wayne

    2010-12-16

    Two concerns were raised by the Government Accountability Office following the 2001 building contaminations via letters containing Bacillus anthracis (BA). These included the: 1) lack of validated sampling methods, and 2) need to use statistical sampling to quantify the confidence of no contamination when all samples have negative results. Critical to addressing these concerns is quantifying the probability of correct detection (PCD) (or equivalently the false negative rate FNR = 1 ? PCD). The PCD/FNR may depend on the 1) method of contaminant deposition, 2) surface concentration of the contaminant, 3) surface material being sampled, 4) sample collection method, 5) sample storage/transportation conditions, 6) sample processing method, and 7) sample analytical method. A review of the literature found 17 laboratory studies that focused on swab, wipe, or vacuum samples collected from a variety of surface materials contaminated by BA or a surrogate, and used culture methods to determine the surface contaminant concentration. These studies quantified performance of the sampling and analysis methods in terms of recovery efficiency (RE) and not PCD/FNR (which left a major gap in available information). Quantifying the PCD/FNR under a variety of conditions is a key aspect of validating sample and analysis methods, and also for calculating the confidence in characterization or clearance decisions based on a statistical sampling plan. A laboratory study was planned to partially fill the gap in PCD/FNR results. This report documents the experimental design developed by Pacific Northwest National Laboratory and Sandia National Laboratories (SNL) for a sponge-wipe method. The study will investigate the effects on key response variables from six surface materials contaminated with eight surface concentrations of a BA surrogate (Bacillus atrophaeus). The key response variables include measures of the contamination on test coupons of surface materials tested, contamination recovered from coupons by sponge-wipe samples, RE, and PCD/FNR. The experimental design involves 16 test runs, to be performed in two blocks of eight runs. Three surface materials (stainless steel, vinyl tile, and ceramic tile) were tested in the first block, while three other surface materials (plastic, painted wood paneling, and faux leather) will be tested in the second block. The eight surface concentrations of the surrogate were randomly assigned to test runs within each block. Some of the concentrations will be very low and may present challenges for deposition, sampling, and analysis. However, such tests are needed to investigate RE and PCD/FNR over the full range of concentrations of interest. In each run, there will be 10 test coupons of each of the three surface materials. A positive control sample will be generated prior to each test sample. The positive control results will be used to 1) calculate RE values for the wipe sampling and analysis method, and 2) fit RE- and PCD-concentration equations, for each of the six surface materials. Data analyses will support 1) estimating the PCD for each combination of contaminant concentration and surface material, 2) estimating the surface concentrations and their uncertainties of the contaminant for each combination of concentration and surface material, 3) estimating RE (%) and their uncertainties for each combination of contaminant concentration and surface material, 4) fitting PCD-concentration and RE-concentration equations for each of the six surface materials, 5) assessing goodness-of-fit of the equations, and 6) quantifying the uncertainty in PCD and RE predictions made with the fitted equations.

  2. Experimental Design for a Sponge-Wipe Study to Relate the Recovery Efficiency and False Negative Rate to the Concentration of a Bacillus anthracis Surrogate for Six Surface Materials

    SciTech Connect

    Piepel, Gregory F.; Amidan, Brett G.; Krauter, Paula; Einfeld, Wayne

    2011-05-01

    Two concerns were raised by the Government Accountability Office following the 2001 building contaminations via letters containing Bacillus anthracis (BA). These included the: 1) lack of validated sampling methods, and 2) need to use statistical sampling to quantify the confidence of no contamination when all samples have negative results. Critical to addressing these concerns is quantifying the false negative rate (FNR). The FNR may depend on the 1) method of contaminant deposition, 2) surface concentration of the contaminant, 3) surface material being sampled, 4) sample collection method, 5) sample storage/transportation conditions, 6) sample processing method, and 7) sample analytical method. A review of the literature found 17 laboratory studies that focused on swab, wipe, or vacuum samples collected from a variety of surface materials contaminated by BA or a surrogate, and used culture methods to determine the surface contaminant concentration. These studies quantified performance of the sampling and analysis methods in terms of recovery efficiency (RE) and not FNR (which left a major gap in available information). Quantifying the FNR under a variety of conditions is a key aspect of validating sample and analysis methods, and also for calculating the confidence in characterization or clearance decisions based on a statistical sampling plan. A laboratory study was planned to partially fill the gap in FNR results. This report documents the experimental design developed by Pacific Northwest National Laboratory and Sandia National Laboratories (SNL) for a sponge-wipe method. The testing was performed by SNL and is now completed. The study investigated the effects on key response variables from six surface materials contaminated with eight surface concentrations of a BA surrogate (Bacillus atrophaeus). The key response variables include measures of the contamination on test coupons of surface materials tested, contamination recovered from coupons by sponge-wipe samples, RE, and FNR. The experimental design involves 16 test runs, performed in two blocks of eight runs. Three surface materials (stainless steel, vinyl tile, and ceramic tile) were tested in the first block, while three other surface materials (plastic, painted wood paneling, and faux leather) were tested in the second block. The eight surface concentrations of the surrogate were randomly assigned to test runs within each block. Some of the concentrations were very low and presented challenges for deposition, sampling, and analysis. However, such tests are needed to investigate RE and FNR over the full range of concentrations of interest. In each run, there were 10 test coupons of each of the three surface materials. A positive control sample was generated at the same time as each test sample. The positive control results will be used to 1) calculate RE values for the wipe sampling and analysis method, and 2) fit RE- and FNR-concentration equations, for each of the six surface materials. Data analyses will support 1) estimating the FNR for each combination of contaminant concentration and surface material, 2) estimating the surface concentrations and their uncertainties of the contaminant for each combination of concentration and surface material, 3) estimating RE (%) and their uncertainties for each combination of contaminant concentration and surface material, 4) fitting FNR-concentration and RE-concentration equations for each of the six surface materials, 5) assessing goodness-of-fit of the equations, and 6) quantifying the uncertainty in FNR and RE predictions made with the fitted equations.

  3. Hypnotizability, not suggestion, influences false memory development.

    PubMed

    Dasse, Michelle N; Elkins, Gary R; Weaver, Charles A

    2015-01-01

    Hypnotizability influences the development of false memories. In Experiment 1, participants heard a positive or negative suggestion regarding hypnosis and then listened to 8 Deese-Roediger-McDermott (DRM) false memory paradigm lists in a hypnotic state. Neither hypnosis nor prehypnotic suggestion affected memory. Highly hypnotizable participants were more accurate in recall and recognition. In Experiment 2, suggestions were delivered in the form of feedback. Participants heard a positive or negative suggestion about their performance prior to either the encoding or retrieval of 8 DRM lists. Neither accurate nor false memories were affected by the suggestion. Highly hypnotizable individuals recognized fewer critical lures if they received a negative suggestion about their performance. These results highlight the unusual role of hypnotizability in the creation of false memories. PMID:25365130

  4. A false-positive hepatobiliary scan: case report and literature review.

    PubMed

    Whalen, J P

    1987-03-01

    This case report describes a false-positive hepatobiliary scan in a young woman suspected to have acute cholecystitis who apparently had none of the reasons stated in the literature for a false-positive scan. The literature review shows that the negative predictive value of hepatobiliary scanning for acute cholecystitis is nearly 100 percent, while the positive predictive value is also quite good if conditions known to cause false-positive scans are ruled out. Common causes of positive hepatobiliary scanning, other than acalculus cholecystitis, include chronic cholecystitis, cholecystitis, hepatitis, alcoholism, total parenteral nutrition, pancreatitis, prolonged fasting, and ingestion of food less than one hour prior to scanning. Whether the postpartum state affects the accuracy of hepatobiliary scanning is speculative. PMID:3819664

  5. Experimental Design for a Sponge-Wipe Study to Relate the Recovery Efficiency and False Negative Rate to the Concentration of a Bacillus anthracis Surrogate for Six Surface Materials

    Microsoft Academic Search

    Gregory F. Piepel; Brett G. Amidan; Paula Krauter; Wayne Einfeld

    2010-01-01

    Two concerns were raised by the Government Accountability Office following the 2001 building contaminations via letters containing Bacillus anthracis (BA). These included the: 1) lack of validated sampling methods, and 2) need to use statistical sampling to quantify the confidence of no contamination when all samples have negative results. Critical to addressing these concerns is quantifying the probability of correct

  6. False Belief vs. False Photographs: A Test of Theory of Mind or Working Memory?

    PubMed Central

    Callejas, Alicia; Shulman, Gordon L.; Corbetta, Maurizio

    2011-01-01

    Theory of mind (ToM), the ability to reason about other people’s thoughts and beliefs, has been traditionally studied in behavioral and neuroimaging experiments by comparing performance in “false belief” and “false photograph” (control) stories. However, some evidence suggests that these stories are not matched in difficulty, complicating the interpretation of results. Here, we more fully evaluated the relative difficulty of comprehending these stories and drawing inferences from them. Subjects read false belief and false photograph stories followed by comprehension questions that probed true (“reality” questions) or false beliefs (“representation” questions) appropriate to the stories. Stories and comprehension questions were read and answered, respectively, more slowly in the false photograph than false belief conditions, indicating their greater difficulty. Interestingly, accuracy on representation questions for false photograph stories was significantly lower than for all other conditions and correlated positively with participants’ working memory span scores. These results suggest that drawing representational inferences from false photo stories is particularly difficult and places heavy demands on working memory. Extensive naturalistic practice with ToM reasoning may enable a more flexible and efficient mental representation of false belief stories, resulting in lower memory load requirements. An important implication of these results is that the differential modulation of right temporal–parietal junction (RTPJ) during ToM and “false photo” control conditions may reflect the documented negative correlation of RTPJ activity with working memory load rather than a specialized involvement in ToM processes. PMID:22069395

  7. Diabetes: What's True and False?

    MedlinePLUS

    ... Digestive System How the Body Works Main Page Diabetes: What's True and False? KidsHealth > Kids > Diabetes Center > ... True or False: Eating Too Much Sugar Causes Diabetes False: When kids get type 1 diabetes , it's ...

  8. Diabetes: What's True and False?

    MedlinePLUS

    ... which are false. Eating too much sugar causes diabetes. False: Type 1 diabetes happens when the cells ... person's risk for developing the disease. People with diabetes can never eat sweets. False: You can have ...

  9. True or False

    NSDL National Science Digital Library

    American Association for the Advancement of Science (; )

    2005-04-18

    If you're told that a particular drug doesn't cure arthritis, there's a good chance you'll start to think it does. That's according to Ian Skurnik at the University of Toronto and Carolyn Yoon at the University of Michigan. They found that when people were told a statement was false, they remembered the statement itself much better than the warning. This Science Update looks at the research, which leads to these findings and offers links to other resources for further inquiry. There are also links to Science Netlinks Lesson plans for use at the 9-12 grade level.

  10. Moon - False Color Mosaic

    NASA Technical Reports Server (NTRS)

    1992-01-01

    This false-color photograph is a composite of 15 images of the Moon taken through three color filters by Galileo's solid-state imaging system during the spacecraft's passage through the Earth-Moon system on December 8, 1992. When this view was obtained, the spacecraft was 425,000 kilometers (262,000 miles) from the Moon and 69,000 kilometers (43,000 miles) from Earth. The false-color processing used to create this lunar image is helpful for interpreting the surface soil composition. Areas appearing red generally correspond to the lunar highlands, while blue to orange shades indicate the ancient volcanic lava flow of a mare, or lunar sea. Bluer mare areas contain more titanium than do the orange regions. Mare Tranquillitatis, seen as a deep blue patch on the right, is richer in titanium than Mare Serenitatis, a slightly smaller circular area immediately adjacent to the upper left of Mare Tranquillitatis. Blue and orange areas covering much of the left side of the Moon in this view represent many separate lava flows in Oceanus Procellarum. The small purple areas found near the center are pyroclastic deposits formed by explosive volcanic eruptions. The fresh crater Tycho, with a diameter of 85 kilometers (53 miles), is prominent at the bottom of the photograph, where part of the Moon's disk is missing.

  11. Apparent telepathy in psychotherapy

    Microsoft Academic Search

    Reginald B. Weiler

    1967-01-01

    Summary A somewhat detailed report has been made on two patients who apparently interacted with each other in order to work out mutual pressing psychodynamic problems, utilizing some process related to mental telepathy which served to coordinate and fulfill their affective needs. The possible participation of the therapist in the “declaration à deux” was considered, and a theoretical postulation of

  12. False color viewing device

    DOEpatents

    Kronberg, J.W.

    1991-05-08

    This invention consists of a viewing device for observing objects in near-infrared false-color comprising a pair of goggles with one or more filters in the apertures, and pads that engage the face for blocking stray light from the sides so that all light reaching, the user`s eyes come through the filters. The filters attenuate most visible light and pass near-infrared (having wavelengths longer than approximately 700 nm) and a small amount of blue-green and blue-violet (having wavelengths in the 500 to 520 nm and shorter than 435 nm, respectively). The goggles are useful for looking at vegetation to identify different species and for determining the health of the vegetation, and to detect some forms of camouflage.

  13. False color viewing device

    DOEpatents

    Kronberg, J.W.

    1992-10-20

    A viewing device for observing objects in near-infrared false-color comprising a pair of goggles with one or more filters in the apertures, and pads that engage the face for blocking stray light from the sides so that all light reaching the user's eyes come through the filters. The filters attenuate most visible light and pass near-infrared (having wavelengths longer than approximately 700 nm) and a small amount of blue-green and blue-violet (having wavelengths in the 500 to 520 nm and shorter than 435 nm, respectively). The goggles are useful for looking at vegetation to identify different species and for determining the health of the vegetation, and to detect some forms of camouflage. 7 figs.

  14. False color viewing device

    DOEpatents

    Kronberg, James W. (108 Independent Blvd., Aiken, SC 29801)

    1992-01-01

    A viewing device for observing objects in near-infrared false-color comprising a pair of goggles with one or more filters in the apertures, and pads that engage the face for blocking stray light from the sides so that all light reaching the user's eyes come through the filters. The filters attenuate most visible light and pass near-infrared (having wavelengths longer than approximately 700 nm) and a small amount of blue-green and blue-violet (having wavelengths in the 500 to 520 nm and shorter than 435 nm, respectively). The goggles are useful for looking at vegetation to identify different species and for determining the health of the vegetation, and to detect some forms of camouflage.

  15. False Position, Double False Position and Cramer's Rule

    ERIC Educational Resources Information Center

    Boman, Eugene

    2009-01-01

    We state and prove the methods of False Position (Regula Falsa) and Double False Position (Regula Duorum Falsorum). The history of both is traced from ancient Egypt and China through the work of Fibonacci, ending with a connection between Double False Position and Cramer's Rule.

  16. False Color Aurora

    NASA Technical Reports Server (NTRS)

    1997-01-01

    Data from NASA's Galileo spacecraft were used to produce this false-color composite of Jupiter's northern aurora on the night side of the planet. The height of the aurora, the thickness of the auroral arc, and the small-scale structure are revealed for the first time. Images in Galileo's red, green, and clear filters are displayed in red, green, and blue respectively. The smallest resolved features are tens of kilometers in size, which is a ten-fold improvement over Hubble Space Telescope images and a hundred-fold improvement over ground-based images.

    The glow is caused by electrically charged particles impinging on the atmosphere from above. The particles travel along Jupiter's magnetic field lines, which are nearly vertical at this latitude. The auroral arc marks the boundary between the 'closed' field lines that are attached to the planet at both ends and the 'open' field lines that extend out into interplanetary space. At the boundary the particles have been accelerated over the greatest distances, and the glow is especially intense.

    The latitude-longitude lines refer to altitudes where the pressure is 1 bar. The image shows that the auroral emissions originate about 500 kilometers (about 310 miles) above this surface. The colored background is light scattered from Jupiter's bright crescent, which is out of view to the right. North is at the top. The images are centered at 57 degrees north and 184 degrees west and were taken on April 2, 1997 at a range of 1.7 million kilometers (1.05 million miles) by Galileo's Solid State Imaging (SSI) system.

    The Jet Propulsion Laboratory, Pasadena, CA manages the mission for NASA's Office of Space Science, Washington, DC.

    This image and other images and data received from Galileo are posted on the World Wide Web, on the Galileo mission home page at: http:// galileo.jpl.nasa.gov. Background information and educational context for the images can be found at: http:/ /www.jpl.nasa.gov/galileo/sepo.

  17. Reduced False Memory after Sleep

    ERIC Educational Resources Information Center

    Fenn, Kimberly M.; Gallo, David A.; Margoliash, Daniel; Roediger, Henry L., III; Nusbaum, Howard C.

    2009-01-01

    Several studies have shown that sleep contributes to the successful maintenance of previously encoded information. This research has focused exclusively on memory for studied events, as opposed to false memories. Here we report three experiments showing that sleep reduces false memories in the Deese-Roediger-McDermott (DRM) memory illusion. False

  18. False-Positive/False-Negative Trade-Offs in Bayesian Model Comparison

    E-print Network

    Draper, David

    an underlying data-generating mechanism MDG (truth) and (b) You keep track of how often Your method recovers known truth (e.g., how often does model-comparison method A correctly identify MDG ?). 3 / 75 #12;Summary (continued) (8) When comparing M1 and M2, let's agree to say that {choosing M2 when MDG

  19. Drug testing welfare recipients--false positives, false negatives, unanticipated opportunities.

    PubMed

    Pollack, Harold A; Danziger, Sheldon; Jayakody, Rukmalie; Seefeldt, Kristin S

    2002-01-01

    Substance abuse and dependence are among the most common psychiatric disorders among pregnant and parenting women. These disorders among welfare recipients have attracted special concern. Chemical testing has been proposed to identify illicit drug use in this population. This analysis scrutinizes the potential value of drug testing, using recent data from the Women's Employment Study and the National Household Survey of Drug Abuse. One-fifth of recipients reported illicit substance use during the previous year. However, less than 5% satisfied diagnostic screening criteria for illicit drug dependence. Most recipients with psychiatric disorders or alcohol dependence reported no recent illicit drug use, and, thus, would not be detected through chemical tests. Although illicit drug users are rarely dependent, many face barriers to self-sufficiency. Screening and assessment programs should distinguish use from dependence, and should also identify alcohol dependence and psychiatric disorders. States should provide a range of treatment services to address these concerns. PMID:11786289

  20. Drug testing welfare recipients—false positives, false negatives, unanticipated opportunities

    Microsoft Academic Search

    Harold A Pollack; Sheldon Danziger; Rukmalie Jayakody; Kristin S Seefeldt

    2002-01-01

    Substance abuse and dependence are among the most common psychiatric disorders among pregnant and parenting women. These disorders among welfare recipients have attracted special concern. Chemical testing has been proposed to identify illicit drug use in this population. This analysis scrutinizes the potential value of drug testing, using recent data from the Women’s Employment Study and the National Household Survey

  1. Accuracy and Apparent Accuracy in Medical Testing

    NSDL National Science Digital Library

    Stuart Boersma

    Unreviewed Activity submitted in preparation for the NNN Writing with Numbers Workshop Students investigate two quantitative issues in the field of medical testing. First, students use two way tables and information about a diagnostic test's sensitivity and specificity to investigate the probability of a patient receiving a false positive result. Second, students learn about the phenomenon of referral bias in medical testing. Students use proportional reasoning to observe the effect of doctor referral rates on the apparent sensitivity and specificity of a screening tool.

  2. Executive Functioning and Preschoolers' Understanding of False Beliefs, False Photographs, and False Signs

    ERIC Educational Resources Information Center

    Sabbagh, Mark A.; Moses, Louis J.; Shiverick, Sean

    2006-01-01

    Two studies were conducted to investigate the specificity of the relationship between preschoolers' emerging executive functioning skills and false belief understanding. Study 1 (N=44) showed that 3- to 5-year-olds' performance on an executive functioning task that required selective suppression of actions predicted performance on false belief…

  3. VESPA: False positive probabilities calculator

    NASA Astrophysics Data System (ADS)

    Morton, Timothy D.

    2015-03-01

    Validation of Exoplanet Signals using a Probabilistic Algorithm (VESPA) calculates false positive probabilities and statistically validates transiting exoplanets. Written in Python, it uses isochrones [ascl:1503.010] and the package simpledist.

  4. Nonlinear dynamics of false bottoms

    NASA Astrophysics Data System (ADS)

    Nizovtseva, Irina; Alexandrov, Dmitri; Ryashko, Lev

    2014-05-01

    Nansen from his observations in the Beaufort Sea published in 1897 noted that heat transfer from the fresh water to the arctic salt water is the only source of ice accretion during the polar summer. This transfer mechanism, unusual at first sight, is responsible for the initiation and evolution of a false bottom ice, changing ice properties to a great extent and affecting various processes while interacting with the ocean and the atmosphere. A false bottom represents a thin layer of ice which forms in summer underneath the floe where fresh water lies between the salt water and the ice. Details of how this process occurs in nature are now emerging from different laboratory and field experiments. The false bottoms appearing at the interface between the fresh and salt water as a result of double-diffusive convection normally lie below surface and under-ice melt ponds. Such false bottoms represent the only significant source of ice growth in the Arctic during the spring-summer period. Their evolution influences the mass balance of the Arctic sea-ice cover recognized as an indicator of climate change. However, the quantity, aerial extent and other properties of false bottoms are difficult to measure because coring under the surface melt ponds leads to direct mixing of surface and under-ice water. This explains why their aerial extent and overall volume is still not known despite the fact that the upper limit of the ice coverage by the false bottom is approximately half of the ice surface. The growth of false bottoms also leads to other important consequences for different physical, chemical and biological processes associated with their dynamics. This study addressed to a broad community of readers is concerned with non-linear behavior of false bottoms including their stochastic dynamics due to possible fluctuations of the main process parameters in the ocean and the atmosphere.

  5. “When true is false, and false is true” [Column

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Many insects and other organisms are called “false” as a common name or the Latin equivalent “pseudo-“ in their scientific names. The column explores the details of and the reasons why so many insects are given such names. Reasons include the vast biodiversity of certain groups, the historical typ...

  6. False fracture of the penis.

    PubMed

    Shah, Darshan K; Paul, Elliot M; Meyersfield, Sanford A; Schoor, Richard A

    2003-06-01

    Penile fracture is an uncommon, but well-described, entity that requires emergent treatment. The classic, "text-book" history, a blow to the erect penis accompanied by a "snap," pain, and immediate detumescence, is not universally present. We report 2 cases of "false" penile fracture, a condition that closely mimics "true" penile fracture. Perhaps the most distinguishing symptoms are the absence of the "snap" and gradual detumescence, both of which suggest false fracture but are not specific. It is our intention to bring this condition to the attention of general urologists who may see it in clinical practice and to guide them in its management. PMID:12809921

  7. Evolutionary Psychology and False Confession

    ERIC Educational Resources Information Center

    Bering, Jesse M.; Shackelford, Todd K.

    2005-01-01

    This paper presents comments on Kassin's review, (see record 2005-03019-002) of the psychology of false confessions. The authors note that Kassin's review makes a compelling argument for the need for legal reform in police interrogation practices. Because his work strikes at the heart of the American criminal justice system--its fairness--the…

  8. The Danger of False Dichotomies.

    ERIC Educational Resources Information Center

    LaBoskey, Vicky Kubler

    1998-01-01

    Responds to an article that examined 10 dichotomies in teacher education (SP 527 128), suggesting that too much time and energy are spent debating false dichotomies and addressing two specific dichotomies (preservice versus inservice and campus versus school site). Recommends that professional educators pool their energy and collaborate (rather…

  9. The Psychology of False Confessions

    Microsoft Academic Search

    Richard P. Conti

    Obtaining a confession is one of the most important aims of police interro- gation, and it is estimated that more than 80% of solved criminal cases are solved by a confession. However, a significant number of confessions that result in wrongful convictions are obtained through coercive questioning. This paper examines false con- fessions and discusses the psychological and social factors

  10. Building false memories without suggestions.

    PubMed

    Foster, Jeffrey L; Garry, Maryanne

    2012-01-01

    People can come to remember doing things they have never done. The question we asked in this study is whether people can systematically come to remember performing actions they never really did, in the absence of any suggestion from the experimenter. People built LEGO vehicles, performing some steps but not others. For half the people, all the pieces needed to assemble each vehicle were laid out in order in front of them while they did the building; for the other half, the pieces were hidden from view. The next day, everyone returned for a surprise recognition test. People falsely and confidently remembered having carried out steps they did not; those who saw all the pieces while they built each vehicle were more likely to correctly remember performing steps they did perform but equally likely to falsely remember performing steps they did not. We explain our results using the source monitoring framework: People used the relationships between actions to internally generate the missing, related actions, later mistaking that information for genuine experience. PMID:22774684

  11. Penrose inequality and apparent horizons

    SciTech Connect

    Ben-Dov, Ishai [Enrico Fermi Institute and Department of Physics, University of Chicago, 5640 S. Ellis Avenue, Chicago, Illinois 60637-1433 (United States)

    2004-12-15

    A spherically symmetric spacetime is presented with an initial data set that is asymptotically flat, satisfies the dominant energy condition, and such that on this initial data M<{radical}(A/16{pi}), where M is the total mass and A is the area of the apparent horizon. This provides a counterexample to a commonly stated version of the Penrose inequality, though it does not contradict the true Penrose inequality.

  12. Apparent horizons in the quasispherical Szekeres models

    NASA Astrophysics Data System (ADS)

    Krasi?ski, Andrzej; Bolejko, Krzysztof

    2012-06-01

    The notion of an apparent horizon (AH) in a collapsing object can be carried over from the Lemaître-Tolman to the quasispherical Szekeres models in three ways: 1. Literally by the definition—the AH is the boundary of the region, in which every bundle of null geodesics has negative expansion scalar. 2. As the locus, at which null lines that are as nearly radial as possible are turned toward decreasing areal radius R. These lines are in general nongeodesic. The name “absolute apparent horizon” (AAH) is proposed for this locus. 3. As the boundary of a region, where null geodesics are turned toward decreasing R. The name “light collapse region” is proposed for this region (which is three-dimensional in every space of constant t); its boundary coincides with the AAH. The AH and AAH coincide in the Lemaître-Tolman models. In the quasispherical Szekeres models, the AH is different from (but not disjoint with) the AAH. Properties of the AAH and light collapse region are investigated, and the relations between the AAH and the AH are illustrated with diagrams using an explicit example of a Szekeres metric. It turns out that an observer who is already within the AH is, for some time, not yet within the AAH. Nevertheless, no light signal can be sent through the AH from the inside. The analogue of the AAH for massive particles is also considered.

  13. False memory susceptibility is correlated with categorisation ability in humans

    PubMed Central

    Hunt, Kathryn; Chittka, Lars

    2014-01-01

    Our memory is often surprisingly inaccurate, with errors ranging from misremembering minor details of events to generating illusory memories of entire episodes. The pervasiveness of such false memories generates a puzzle: in the face of selection pressure for accuracy of memory, how could such systematic failures have persisted over evolutionary time? It is possible that memory errors are an inevitable by-product of our adaptive memories and that semantic false memories are specifically connected to our ability to learn rules and concepts and to classify objects by category memberships. Here we test this possibility using a standard experimental false memory paradigm and inter-individual variation in verbal categorisation ability. Indeed it turns out that the error scores are significantly negatively correlated, with those individuals scoring fewer errors on the categorisation test being more susceptible to false memory intrusions in a free recall test. A similar trend, though not significant, was observed between individual categorisation ability and false memory susceptibility in a word recognition task. Our results therefore indicate that false memories, to some extent, might be a by-product of our ability to learn rules, categories and concepts. PMID:25254105

  14. Proactive and Retroactive Effects of Negative Suggestion

    ERIC Educational Resources Information Center

    Brown, Alan S.; Brown, Christine M.; Mosbacher, Joy L.; Dryden, W. Erich

    2006-01-01

    The negative effects of false information presented either prior to (proactive interference; PI) or following (retroactive interference; RI) true information was examined with word definitions (Experiment 1) and trivia facts (Experiment 2). Participants were explicitly aware of which information was true and false when shown, and true-false

  15. Venus - False Color of Bereghinya Planitia

    NASA Technical Reports Server (NTRS)

    1992-01-01

    This false color Magellan image shows a portion of Bereghinya Planitia (plains) in the northern hemisphere of Venus, centered at 31 degrees north latitude, 43 degrees east longitude. The area is 260 kilometers (160 miles) wide and 330 kilometers (200 miles) long. This image was produced from Magellan radar data collected in Cycle 2 of the mission. Cycle 2 was completed January 15, 1992. The area was not imaged during the first cycle because of superior conjunction when the sun was between the Earth and Venus, preventing communication with the spacecraft. This image contains examples of several of the major geologic terrains on Venus and illustrates the basic stratigraphy or sequence of geologic events. The oldest terrains appear as bright, highly-fractured or chaotic highlands rising out of the plains. This is seen in the upper right and lower left quadrants of the image. The chaotic highlands, sometimes called tessera, may represent older and thicker crustal material and occupy about 15 percent of the surface of Venus. Plains surround and embay the fractured highland tessera. Plains are formed by fluid volcanic flows that may have once formed vast lava seas which covered all the low lying surfaces. Plains comprise more than 80 percent of the surface of Venus. The most recent activity in the region is volcanism that produced the radar bright flows best seen in the lower right quadrant of the image. The lava flows in this image are associated with the shield volcano Tepev Mons whose summit is near the lower left corner of the image. The flows are similar to the darker plains volcanics, but apparently have more rugged surfaces that more efficiently scatter the radar signal back to the spacecraft. The geologic sequence is early fracturing of the tessera, flooding by extensive plains lavas and scattered, less extensive individual flows on the plains surface. The simulated hues are based on color images recorded by the Soviet Venera 13 and 14 spacecraft.

  16. Southern Spring in False Color

    NASA Technical Reports Server (NTRS)

    2004-01-01

    [figure removed for brevity, see original site]

    The Odyssey spacecraft has completed a full Mars year of observations of the red planet. For the next several weeks the Image of the Day will look back over this first mars year. It will focus on four themes: 1) the poles - with the seasonal changes seen in the retreat and expansion of the caps; 2) craters - with a variety of morphologies relating to impact materials and later alteration, both infilling and exhumation; 3) channels - the clues to liquid surface flow; and 4) volcanic flow features. While some images have helped answer questions about the history of Mars, many have raised new questions that are still being investigated as Odyssey continues collecting data as it orbits Mars.

    This image was collected June 25, 2003 during the southern spring season. This false color image shows both the layered ice cap and darker 'spots' that are seen only when the sun first lights the polar surface.

    Image information: VIS instrument. Latitude -82.3, Longitude 306 East (54 West). 19 meter/pixel resolution.

    Note: this THEMIS visual image has not been radiometrically nor geometrically calibrated for this preliminary release. An empirical correction has been performed to remove instrumental effects. A linear shift has been applied in the cross-track and down-track direction to approximate spacecraft and planetary motion. Fully calibrated and geometrically projected images will be released through the Planetary Data System in accordance with Project policies at a later time.

    NASA's Jet Propulsion Laboratory manages the 2001 Mars Odyssey mission for NASA's Office of Space Science, Washington, D.C. The Thermal Emission Imaging System (THEMIS) was developed by Arizona State University, Tempe, in collaboration with Raytheon Santa Barbara Remote Sensing. The THEMIS investigation is led by Dr. Philip Christensen at Arizona State University. Lockheed Martin Astronautics, Denver, is the prime contractor for the Odyssey project, and developed and built the orbiter. Mission operations are conducted jointly from Lockheed Martin and from JPL, a division of the California Institute of Technology in Pasadena.

  17. Pathways to False Allegations of Sexual Assault

    Microsoft Academic Search

    Jessica Engle; William ODonohue

    2012-01-01

    Not all allegations of sexual assault are true. Unfortunately, there has been little work on understanding the prevalence of false allegations or pathways to these. This paper proposes 11 pathways to false allegations of sexual assault: (a) lying, (b) implied consent, (c) false memories, (d) intoxication, (e) antisocial personality disorder, (f) borderline personality disorder, (g) histrionic personality disorder, (h) delirium,

  18. 21 CFR 868.5935 - External negative pressure ventilator.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ...2010-04-01 2010-04-01 false External negative pressure ventilator. 868...Therapeutic Devices § 868.5935 External negative pressure ventilator. (a) Identification. An external negative pressure ventilator...

  19. Preoperative and intraoperative infection workup in apparently aseptic revision shoulder arthroplasty.

    PubMed

    Updegrove, Gary F; Armstrong, April D; Kim, H-M Mike

    2015-03-01

    The possibility of infection should be considered in every revision shoulder arthroplasty even in the absence of clinical symptoms and signs of infection because indolent infection is prevalent. Detection of infection in apparently aseptic failed arthroplasties poses a diagnostic challenge as the conventional principles and criteria used for hip and knee arthroplasty are not generally applicable. Propionibacterium acnes and Staphylococcus epidermidis are among the infectious organisms most commonly identified in such situations. Serum inflammatory markers are essential but are often unreliable as they have poor sensitivity in the shoulder. Preoperative shoulder joint aspiration culture is an important step but is subject to high false-negative rates. Lower cutoff values of synovial fluid analysis are used for detection of periprosthetic infection than for native joint infection as demonstrated in the knee literature. Intraoperatively, frozen section should be considered when a diagnosis of infection has not been established even in the presence of clinical suspicion. Gram stain is currently not recommended because of its low sensitivity and negative predictive value. Intraoperative culture is critical and should be performed whenever there is clinical suspicion of infection. Unexpected positive intraoperative cultures are not uncommon, and 6% to 25% of them appear to represent true infection as demonstrated with positive follow-up cultures or subsequent development of infection. In revision shoulder arthroplasty, determining the presence of infection can be difficult. A standardized approach is needed to determine the best course of treatment in this particular clinical setting. PMID:25487903

  20. Children's False Memory and True Disclosure in the Face of Repeated Questions

    ERIC Educational Resources Information Center

    Schaaf, Jennifer M.; Alexander, Kristen Weede; Goodman, Gail S.

    2008-01-01

    The current study was designed to investigate children's memory and suggestibility for events differing in valence (positive or negative) and veracity (true or false). A total of 82 3- and 5-year-olds were asked repeated questions about true and false events, either in a grouped order (i.e., all questions about a certain event asked consecutively)…

  1. Geophysics Fatally Flawed by False Fundamental Philosophy

    NASA Astrophysics Data System (ADS)

    Myers, L. S.

    2004-05-01

    For two centuries scientists have failed to realize Laplace's nebular hypothesis \\(1796\\) of Earth's creation is false. As a consequence, geophysicists today are misinterpreting and miscalculating many fundamental aspects of the Earth and Solar System. Why scientists have deluded themselves for so long is a mystery. The greatest error is the assumption Earth was created 4.6 billion years ago as a molten protoplanet in its present size, shape and composition. This assumption ignores daily accretion of more than 200 tons/day of meteorites and dust, plus unknown volumes of solar insolation that created coal beds and other biomass that increased Earth's mass and diameter over time! Although the volume added daily is minuscule compared with Earth's total mass, logic and simple addition mandates an increase in mass, diameter and gravity. Increased diameter from accretion is proved by Grand Canyon stratigraphy that shows a one kilometer increase in depth and planetary radius at a rate exceeding three meters \\(10 ft\\) per Ma from start of the Cambrian \\(540 Ma\\) to end of the Permian \\(245 Ma\\)-each layer deposited onto Earth's surface. This is unequivocal evidence of passive external growth by accretion, part of a dual growth and expansion process called "Accreation" \\(creation by accretion\\). Dynamic internal core expansion, the second stage of Accreation, did not commence until the protoplanet reached spherical shape at 500-600 km diameter. At that point, gravity-powered compressive heating initiated core melting and internal expansion. Expansion quickly surpassed the external accretion growth rate and produced surface volcanoes to relieve explosive internal tectonic pressure and transfer excess mass (magma)to the surface. Then, 200-250 Ma, expansion triggered Pangaea's breakup, first sundering Asia and Australia to form the Pacific Ocean, followed by North and South America to form the Atlantic Ocean, by the mechanism of midocean ridges, linear underwater volcanoes, that enable planetary expansion the same way cranial sutures permit human skulls to grow to maturity. Expansion is shown by the Asian and Australian trenches, from Kamchatka to the Marianas, and from Samoa to the tip of Macquarie Ridge south of New Zealand, that are mirror images of the western coasts of North and South America. This is clear evidence neither the Atlantic nor the Pacific Ocean existed 250 Ma when Earth was much smaller. In just 250 Ma external accretion and internal core expansion increased Earth's diameter from 7640 km to 12,735 km and increased total surface area to 361,060,000 sq. km, the area occupied by today's oceans-oceans that did not exist 250 Ma when Earth was slightly larger than Mars is today \\(6787 km\\). The fallacy of the nebular hypothesis did not become apparent until after Oliver and Isacks introduced the concept of subduction in 1967. Subduction was based on the false assumption that Earth's diameter is constant and unchanging, and spawned the theory of Plate Tectonics that "revolutionized" geophysics in a short period of time-a "revolution" destined for failure. Evidence is presented showing all solar bodies originate as comets \\(fragments of supernovae explosions\\) captured by the Sun that become meteoroids or asteroids by external accretion of meteorites and dust from over 370 known meteor streams.\\(Terentjeva, 1964\\) Accreation replaces the nebular hypothesis and rejuvenates Carey's Earth Expansion theory that, unfortunately, was pushed aside by plate tectonics because it lacked a plausible mechanism. However, expansion carries an ultimate threat to Mankind's tenure on Earth and exploration of Mars as the future home of Mankind takes on added significance.

  2. Negative mass

    NASA Astrophysics Data System (ADS)

    Hammond, Richard T.

    2015-03-01

    Some physical aspects of negative mass are examined. Several unusual properties, such as the ability of negative mass to penetrate any armor, are analysed. Other surprising effects include the bizarre system of negative mass chasing positive mass, naked singularities and the violation of cosmic censorship, wormholes, and quantum mechanical results as well. In addition, a brief look into the implications for strings is given.

  3. 19 CFR 11.13 - False designations of origin and false descriptions; false marking of articles of gold or silver.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ...descriptions; false marking of articles of gold or silver. 11.13 Section 11.13...descriptions; false marking of articles of gold or silver. (a) Articles which...Articles made in whole or in part of gold or silver or alloys thereof...

  4. 19 CFR 11.13 - False designations of origin and false descriptions; false marking of articles of gold or silver.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ...descriptions; false marking of articles of gold or silver. 11.13 Section 11.13...descriptions; false marking of articles of gold or silver. (a) Articles which...Articles made in whole or in part of gold or silver or alloys thereof...

  5. 19 CFR 11.13 - False designations of origin and false descriptions; false marking of articles of gold or silver.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ...descriptions; false marking of articles of gold or silver. 11.13 Section 11.13...descriptions; false marking of articles of gold or silver. (a) Articles which...Articles made in whole or in part of gold or silver or alloys thereof...

  6. 19 CFR 11.13 - False designations of origin and false descriptions; false marking of articles of gold or silver.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ...descriptions; false marking of articles of gold or silver. 11.13 Section 11.13...descriptions; false marking of articles of gold or silver. (a) Articles which...Articles made in whole or in part of gold or silver or alloys thereof...

  7. 19 CFR 11.13 - False designations of origin and false descriptions; false marking of articles of gold or silver.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ...descriptions; false marking of articles of gold or silver. 11.13 Section 11.13...descriptions; false marking of articles of gold or silver. (a) Articles which...Articles made in whole or in part of gold or silver or alloys thereof...

  8. ``False Positive,'' an Apt Term and Concept for Volcanologists

    NASA Astrophysics Data System (ADS)

    Wunderman, R.

    2010-12-01

    A less-than-bold prediction is that signals that could presage an eruption, but later turn out not to have been predictive (false positives), will continue to vex volcanologists and societies touched by volcanic processes. At present, even at the most carefully monitored volcanoes, many remote-sensing, geophysical, and geochemical clues are often incompletely diagnostic. Even assessing multiple kinds of data cannot ensure successful prediction of eruption or eruptive behavior. Although we’ve witnessed improvements in instrumentation, a growing number of instructive examples, and advances in understanding, the concept of false positives might elevate public understanding since the term is in common use (eg., medical tests). The term helps reveal inherent uncertainty to the press and public, with much-needed emphasis on the limits of the data. Such understanding among the public is critical when scientists forecast an eruption that fails to materialize (“cry wolf”), a circumstance that can have profound negative consequences, including loss of credibility. Bayes’ theorem can calculate probabilities as well as the rates of false positives and false negatives. The rates are a function of both the accuracy of the test and the actual rate of occurrence of the phenomena in question. Globally, rates of occurrence differ for various volcanological processes. For example, dome extrusion is common, whereas caldera collapse, comparatively rare. The latter’s rarity may suggest caution in interpreting precursory signals that could indicate that outcome. Despite the risk of false positives, it may be appropriate to heed test results, even those of marginal reliability, because the consequences of disaster are much greater than the cost of avoidance. For example, risks of uncertain ash plumes detected by VAACs with remote sensing may be minimized by altering an aircraft’s route, a choice less onerous than confronting the danger of ash encounter.

  9. False positive detection of peanut residue in liquid caramel coloring using commercial ELISA kits.

    PubMed

    Stelk, T; Niemann, L; Lambrecht, D M; Baumert, J L; Taylor, S L

    2013-07-01

    Initial food industry testing in our laboratory using enzyme-linked immunosorbent assay (ELISA) methods indicated that the darkest caramel color (class IV) unexpectedly contained traces of peanut protein, a potential undeclared allergen issue. Caramel production centers on the heating of sugars, often glucose, under controlled heat and chemical processing conditions with other ingredients including ammonia, sulfite, and/or alkali salts. These ingredients should not contain any traces of peanut residue. We sought to determine the reliability of commercially available peanut allergen ELISA methods for detection of apparent peanut residue in caramel coloring. Caramel color samples of classes I, II, III, and IV were obtained from 2 commercial suppliers and tested using 6 commercially available quantitative and qualitative peanut ELISA kits. Five lots of class IV caramel color were spiked with a known concentration of peanut protein from light roasted peanut flour to assess recovery of peanut residue using a spike and recovery protocol with either 15 ppm or 100 ppm peanut protein on a kit-specific basis. A false positive detection of peanut protein was found in class IV caramel colors with a range of 1.2 to 17.6 parts per million recovered in both spiked and unspiked liquid caramel color samples. ELISA kit spike/recovery results indicate that false negative results might also be obtained if peanut contamination were ever to actually exist in class IV caramel color. Manufacturers of peanut-free products often test all ingredients for peanut allergen residues using commercial ELISA kits. ELISA methods are not reliable for the detection of peanut in class IV caramel ingredients and their use is not recommended with this matrix. PMID:23647653

  10. Emotional content of true and false memories

    Microsoft Academic Search

    Cara Laney; Elizabeth F. Loftus

    2008-01-01

    Many people believe that emotional memories (including those that arise in therapy) are particularly likely to represent true events because of their emotional content. But is emotional content a reliable indicator of memory accuracy? The current research assessed the emotional content of participants’ pre-existing (true) and manipulated (false) memories for childhood events. False memories for one of three emotional childhood

  11. Effects of Instructions on False Recognition.

    ERIC Educational Resources Information Center

    Mueller, John H.; And Others

    Four experiments were conducted to examine the effects of various processing instructions on the rate of false recognition. The continuous single-item procedure was used, and false recognitions of four types were examined: synonyms, antonyms, nonsemantic associates, and homonyms. The instructions encouraged subjects to think of associates, usages…

  12. Improbability Filtering for Rejecting False Positives

    Microsoft Academic Search

    Brett Browning; Michael H. Bowling; Manuela M. Veloso

    2002-01-01

    Abstract - In this paper we describe a novel approach, called improbability filtering, to rejecting false - positive observations from degrading the tracking performance of an Extended Kalman - Bucy filter False - positives, incorrect observations reported with a high confidence, are a form of non - Gaussian white noise and therefore degrade the tracking performance of an Extended Kalman

  13. LVIS Tree Height Cross Section (false color)

    NSDL National Science Digital Library

    Randall Jones

    1999-09-17

    This animation starts with a false-color map of tree heights north of San Jose, Costa Rica, and changes to a close-up 3D cut-away of a section of the forest, also in false color. Data from LVIS observations taken in March, 1998.

  14. Breast cancer screening: evidence for false reassurance?

    Microsoft Academic Search

    R. de Gelder; E. van As; M. M. A. Tilanus-Linthorst; C. C. M. Bartels; R. Boer; G. Draisma; H. J. de Koning

    2008-01-01

    Tumour stage distribution at repeated mammography screening is, unexpectedly, often not more favourable than stage distribution at first screenings. False reassurance, i.e., delayed symptom presentation due to having participated in earlier screening rounds, might be associated with this, and unfavourably affect prognosis. To assess the role of false reassurance in mammography screening, a consecutive group of 155 breast cancer patients

  15. Negative Influence

    NSDL National Science Digital Library

    William C. Robertson, Ph.D.

    2006-01-01

    This chapter is all about negative numbers, and how to deal with them. They're not all that difficult to understand, but for some reason people get just a little uptight when they see computations involving negative numbers. I'm guessing that the apprehension results from the view that negative numbers mean there are more rules to follow--rules you don't necessarily understand. Well, we'll try and correct that.

  16. Reducing False Positives in Runtime Analysis of Deadlocks

    NASA Technical Reports Server (NTRS)

    Bensalem, Saddek; Havelund, Klaus; Clancy, Daniel (Technical Monitor)

    2002-01-01

    This paper presents an improvement of a standard algorithm for detecting dead-lock potentials in multi-threaded programs, in that it reduces the number of false positives. The standard algorithm works as follows. The multi-threaded program under observation is executed, while lock and unlock events are observed. A graph of locks is built, with edges between locks symbolizing locking orders. Any cycle in the graph signifies a potential for a deadlock. The typical standard example is the group of dining philosophers sharing forks. The algorithm is interesting because it can catch deadlock potentials even though no deadlocks occur in the examined trace, and at the same time it scales very well in contrast t o more formal approaches to deadlock detection. The algorithm, however, can yield false positives (as well as false negatives). The extension of the algorithm described in this paper reduces the amount of false positives for three particular cases: when a gate lock protects a cycle, when a single thread introduces a cycle, and when the code segments in different threads that cause the cycle can actually not execute in parallel. The paper formalizes a theory for dynamic deadlock detection and compares it to model checking and static analysis techniques. It furthermore describes an implementation for analyzing Java programs and its application to two case studies: a planetary rover and a space craft altitude control system.

  17. Simultaneous Genotype Calling and Haplotype Phasing Improves Genotype Accuracy and Reduces False-Positive

    E-print Network

    Yu, Zhaoxia

    of data from the Wellcome Trust Case Control Consortium bipolar disorder and type 2 diabetes studies. For bipolar disorder, the genotype calls in the original study yield 25 markers with apparent false-positive association with bipolar disorder at a p

  18. István Mészáros, the unconscious, and false consciousness.

    PubMed

    Rendon, Mario

    2013-06-01

    Hungarian philosopher István Mészáros' more recent work expands our understanding of consciousness in a way that is particularly relevant to psychoanalysis. He underscores the tragedy of consciousness, increasingly alienated from the totality of our social and individual being, and replaced by its false analog. To make sustainable an anachronistic type of vertical social structure, ideologists of false consciousness join arms with those who control society's historically developed means to reproduce itself and its members. This results in the social phenomenon of alienation, whereby actively produced false consciousness creates a correlate individual unconscious. Mészáros' theory seems compatible with the psychoanalytic paradigms developed by Karen Horney and the Neo-Freudians. PMID:23722401

  19. Apparent horizon in fluid-gravity duality

    SciTech Connect

    Booth, Ivan; Heller, Michal P.; Plewa, Grzegorz; Spalinski, Michal [Department of Mathematics and Statistics, Memorial University of Newfoundland, St. John's, Newfoundland and Labrador, A1C 5S7 (Canada); Instituut voor Theoretische Fysica, Universiteit van Amsterdam, Science Park 904, 1090 GL Amsterdam (Netherlands); Soltan Institute for Nuclear Studies, Hoza 69, 00-681 Warsaw (Poland); Soltan Institute for Nuclear Studies, Hoza 69, 00-681 Warsaw (Poland) and Physics Department, University of Bialystok, 15-424 Bialystok (Poland)

    2011-05-15

    This article develops a computational framework for determining the location of boundary-covariant apparent horizons in the geometry of conformal fluid-gravity duality in arbitrary dimensions. In particular, it is shown up to second order and conjectured to hold to all orders in the gradient expansion that there is a unique apparent horizon which is covariantly expressible in terms of fluid velocity, temperature, and boundary metric. This leads to the first explicit example of an entropy current defined by an apparent horizon and opens the possibility that in the near-equilibrium regime there is preferred foliation of apparent horizons for black holes in asymptotically anti-de Sitter spacetimes.

  20. Stereotypes influence false memories for imagined events.

    PubMed

    Kleider, Heather M; Goldinger, Stephen D; Knuycky, Leslie

    2008-02-01

    Two experiments tested the influences of vivid imagery and person schemata on eyewitness accuracy. Participants watched an event sequence including actors performing stereotype-consistent and inconsistent actions. Additionally, participants either read descriptions of actions (Experiment 1) or vividly imagined actions (Experiment 2). After either 30 minutes or 2 days, recognition memory, source memory, and remember/know judgements were made. After 2 days, false alarms to imagined events increased, relative to the 30-minute test; those false alarms were more often misattributed to stereotype-consistent actors, relative to the same actions in the reading condition. In addition, the accompanying remember judgements were higher for false alarms to imagined events, relative to read events, regardless of stereotype consistency. Overall the results suggest that, over time, vivid imagery reinforces schema activation, increasing stereotype-consistent false memories. PMID:18286415

  1. Can language prediction lead to false memories? 

    E-print Network

    Speed, Laura

    2010-06-30

    The present study sought to investigate the use of prediction during sentence comprehension and whether prediction could lead to false memories for sentences when the ending of a sentence is not properly recovered. Participants listened to sentences...

  2. 20 CFR 356.3 - False claims.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ...Benefits RAILROAD RETIREMENT BOARD ADMINISTRATIVE REMEDIES FOR FRAUDULENT CLAIMS OR STATEMENTS CIVIL MONETARY PENALTY INFLATION ADJUSTMENT § 356.3 False claims. In the case of penalties assessed under 31 U.S.C. 3729 based on actions...

  3. 20 CFR 356.3 - False claims.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ...Benefits RAILROAD RETIREMENT BOARD ADMINISTRATIVE REMEDIES FOR FRAUDULENT CLAIMS OR STATEMENTS CIVIL MONETARY PENALTY INFLATION ADJUSTMENT § 356.3 False claims. In the case of penalties assessed under 31 U.S.C. 3729 based on actions...

  4. 20 CFR 356.3 - False claims.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ...Benefits RAILROAD RETIREMENT BOARD ADMINISTRATIVE REMEDIES FOR FRAUDULENT CLAIMS OR STATEMENTS CIVIL MONETARY PENALTY INFLATION ADJUSTMENT § 356.3 False claims. In the case of penalties assessed under 31 U.S.C. 3729 based on actions...

  5. 20 CFR 356.3 - False claims.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ...Benefits RAILROAD RETIREMENT BOARD ADMINISTRATIVE REMEDIES FOR FRAUDULENT CLAIMS OR STATEMENTS CIVIL MONETARY PENALTY INFLATION ADJUSTMENT § 356.3 False claims. In the case of penalties assessed under 31 U.S.C. 3729 based on actions...

  6. 20 CFR 356.3 - False claims.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ...Benefits RAILROAD RETIREMENT BOARD ADMINISTRATIVE REMEDIES FOR FRAUDULENT CLAIMS OR STATEMENTS CIVIL MONETARY PENALTY INFLATION ADJUSTMENT § 356.3 False claims. In the case of penalties assessed under 31 U.S.C. 3729 based on actions...

  7. Animal cognition: bumble bees suffer 'false memories'.

    PubMed

    Reinhard, Judith

    2015-03-16

    The existence of 'false memories', where individuals remember events that they have never actually experienced, is well established in humans. Now a new study reports that insects similarly form illusory memories through merging of memory traces. PMID:25784044

  8. Right ventricular false tendons, a cadaveric approach

    Microsoft Academic Search

    Marios Loukas; Christopher T. Wartmann; R. Shane Tubbs; Nihal Apaydin; Robert G. Louis Jr; Brandie Black; Robert Jordan

    2008-01-01

    Left ventricular false tendons (LFTs) have been extensively described and recognized by gross anatomic studies. However, there\\u000a is very little information available regarding right ventricular false tendons (RFTs). The aim of our study, therefore, was\\u000a to explore and delineate the morphology, topography and morphometry of the RFTs, and provide a comprehensive picture of their\\u000a anatomy across a broad range of

  9. Review article: the false-bottom ice

    NASA Astrophysics Data System (ADS)

    Alexandrov, D. V.; Jouzel, J.; Nizovtseva, I.; Ryashko, L. B.

    2013-11-01

    Nansen from his observations in the Beaufort Sea published in 1897 noted that heat transfer from the fresh water (with a~temperature of 0 °C) to the arctic salt water (with a temperature of -1.6 °C) is the only source of ice accretion during the polar summer. This transfer mechanism, unusual at first sight, is responsible for the initiation and evolution of a false bottom ice, changing ice properties to a great extent and affecting various processes while interacting with the ocean and the atmosphere. The processes of false bottom ice growth from below (i.e. from the ocean to the atmosphere) become of prime importance in the era of global warming and climate change. In this review, we summarize the theoretical approaches, field and laboratory observations, conducted during more than 100 yr, in order to address the problem of false bottoms to a broad community of readers. We also discuss the recent modeling advances to which we have contributed. A "false bottom" is a thin layer of ice which forms in summer underneath the floe, where fresh water lies between the salt water and the ice. Such false bottoms represent the only significant source of ice growth in the Arctic during the spring-summer period. Their evolution influences the mass balance of the Arctic sea-ice cover, which is recognized as an indicator of climate change. However, the quantity, aerial extent and other properties of false bottoms are difficult to measure because coring under the surface melt ponds leads to direct mixing of surface and under-ice water. This explains why their aerial extent and overall volume is still not known despite the fact that the upper limit of the present-day estimate of the false bottom ice coverage is approximately half of the sea ice surface. The growth of false bottoms also leads to other important consequences for various physical, chemical and biological processes associated with their dynamics.

  10. Astronomy Ranking Task: Apparent and Absolute Magnitude

    E-print Network

    Farritor, Shane

    Astronomy Ranking Task: Apparent and Absolute Magnitude Exercise #4 Description: The table below provides partial magnitude and distance information for five stars (A - E). Star Name Apparent Magnitude Absolute Magnitude Distance from Earth (parsecs) A -1 3 B 5 1 C 0 10 D 1 10,000 E 3 3 A. Ranking

  11. Astronomy Ranking Task: Apparent and Absolute Magnitude

    E-print Network

    Farritor, Shane

    Astronomy Ranking Task: Apparent and Absolute Magnitude Exercise #2 Description: The figure below magnitude. Ranking Order: Greatest 1 _______ 2 _______ 3 _______ 4 _______ 5 _______ Least Or, the apparent magnitude number would be the same for each star. ______ (indicate with check mark). Carefully explain your

  12. Testing of Apparent Child Sex Offender Clustering

    Microsoft Academic Search

    Kenneth A. Clontz; J. Gayle Mericle

    During a previous research project, the authors of this work noticed an apparent clustering of registered child sexual offenders as reflected by street addresses. The following research seeks to determine whether or not this effect is real or apparent. If this correlation exists, does it further relate to income levels of the neighborhood as established by the 2000 U.S. Census

  13. Pleiotropy, apparent stabilizing selection and uncovering fitness

    E-print Network

    Sokolowski, Marla

    Pleiotropy, apparent stabilizing selection and uncovering fitness optima Katrina McGuigan1 , Locke ow- ing to joint effects with fitness, and results in the genetic variation being concentrated with high levels of genetic vari- ation can be used to uncover fitness optima that are defined by apparent

  14. 27 CFR 478.128 - False statement or representation.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... false False statement or representation. 478.128 Section 478...478.128 False statement or representation. (a) Any person who knowingly makes any false statement or representation in applying for any...

  15. 27 CFR 478.128 - False statement or representation.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... false False statement or representation. 478.128 Section 478...478.128 False statement or representation. (a) Any person who knowingly makes any false statement or representation in applying for any...

  16. 27 CFR 478.128 - False statement or representation.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... false False statement or representation. 478.128 Section 478...478.128 False statement or representation. (a) Any person who knowingly makes any false statement or representation in applying for any...

  17. 7 CFR 275.13 - Review of negative cases.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ...2011-01-01 2011-01-01 false Review of negative cases. 275.13 Section...STAMP AND FOOD DISTRIBUTION PROGRAM PERFORMANCE REPORTING SYSTEM Quality Control (QC) Reviews § 275.13 Review of negative cases. (a)...

  18. 7 CFR 275.13 - Review of negative cases.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ...2013-01-01 2013-01-01 false Review of negative cases. 275.13 Section...STAMP AND FOOD DISTRIBUTION PROGRAM PERFORMANCE REPORTING SYSTEM Quality Control (QC) Reviews § 275.13 Review of negative cases. (a)...

  19. 7 CFR 275.13 - Review of negative cases.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ...2014-01-01 2014-01-01 false Review of negative cases. 275.13 Section...STAMP AND FOOD DISTRIBUTION PROGRAM PERFORMANCE REPORTING SYSTEM Quality Control (QC) Reviews § 275.13 Review of negative cases. (a)...

  20. 7 CFR 275.13 - Review of negative cases.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ...2012-01-01 2012-01-01 false Review of negative cases. 275.13 Section...STAMP AND FOOD DISTRIBUTION PROGRAM PERFORMANCE REPORTING SYSTEM Quality Control (QC) Reviews § 275.13 Review of negative cases. (a)...

  1. MTS in false positive reduction for multi-sensor fusion

    NASA Astrophysics Data System (ADS)

    Woodley, Robert; Gosnell, Michael; Cudney, Elizabeth

    2014-05-01

    The Mahalanobis Taguchi System (MTS) is a relatively new tool in the vehicle health maintenance domain, but has some distinct advantages in current multi-sensor implementations. The use of Mahalanobis Spaces (MS) allows the algorithm to identify characteristics of sensor signals to identify behaviors in machines. MTS is extremely powerful with the caveat that the correct variables are selected to form the MS. In this research work, 56 sensors monitor various aspects of the vehicles. Typically, using the MTS process, identification of useful variables is preceded by validation of the measurements scale. However, the MTS approach doesn't directly include any mitigating steps should the measurement scale not be validated. Existing work has performed outlier removal in construction of the MS, which can lead to better validation. In our approach, we modify the outlier removal process with more liberal definitions of outliers to better identify variables' impact prior to identification of useful variables. This subtle change substantially lowered the false positive rate due to the fact that additional variables were retained. Traditional MTS approaches identify useful variables only to the extent they provide usefulness in identifying the positive (abnormal) condition. The impact of removing false negatives is not included. Initial results show our approach can reduce false positive values while still maintaining complete fault identification for this vehicle data set.

  2. An investigation of false positive dosimetry results

    SciTech Connect

    Lewandowski, M.A.; Davis, S.A.; Goff, T.E.; Wu, C.F.

    1996-12-31

    The Waste Isolation Pilot Plant (WIPP) is a facility designed for the demonstration of the safe disposal of transuranic waste. Currently, the radiation source term is confined to sealed calibration and check sources since WIPP has not received waste for disposal. For several years the WIPP Dosimetry Group has operated a Harshaw Model 8800C reader to analyze Harshaw 8801-7776 thermoluminescent cards (3 TLD-700 and 1 TLD-600) with 8805 holder. The frequency of false positive results for quarterly dosimeter exchanges is higher than desired by the Dosimetry Group management. Initial observations suggested that exposure to intense ambient sunlight may be responsible for the majority of the false positive readings for element 3. A study was designed to investigate the possibility of light leaking through the holder and inducing a signal in element 3. This paper discusses the methods and results obtained, with special emphasis placed on recommendations to reduce the frequency of light-induced false positive readings.

  3. Color updating on the apparent motion path.

    PubMed

    Chong, Edmund; Hong, Sang Wook; Shim, Won Mok

    2014-01-01

    When a static stimulus appears successively at two distant locations, we perceive illusory motion of the stimulus across them-long-range apparent motion (AM). Previous studies have shown that when the apparent motion stimuli differ in shape, interpolation between the two shapes is perceived across the AM path. In contrast, the perceived color during AM has been shown to abruptly change from the color of the first stimulus into that of the second, suggesting interpolation does not occur for color during AM. Here, we report the first evidence to our knowledge, that an interpolated color, distinct from the colors of either apparent motion stimulus, is represented as the intermediate percept on the path of apparent motion. Using carefully chosen target colors-cyan, pink, and lime-that are perceptually and neurally intermediate between blue and green, orange and magenta, and green and orange respectively, we show that detection of a target presented on the apparent motion path was impaired when the color of the target was "in-between" the initial and terminal stimulus colors. Furthermore, we show that this feature-specific masking effect for the intermediate color cannot be accounted for by color similarity between the intermediate color and the color of the terminal inducer. Our findings demonstrate that intermediate colors can be interpolated over the apparent motion trajectory as in the case of shape, possibly involving similar interpolation processes for shape and color during apparent motion. PMID:25527146

  4. Loop transformations to prevent false sharing

    SciTech Connect

    Granston, E.D. [Rice Univ., Houston, TX (United States); Montaut, T.; Bodin, F. [IRISA, Rennes (France)

    1995-08-01

    To date, page management in shared virtual memory (SVM) systems has been primarily the responsibility of the run-time system. However, there are some problems that are difficult to resolve efficiently at run time. Chief among these is false sharing. In this paper, a loop transformation theory is developed for identifying and eliminating potential sources of multiple-writer false sharing and other sources of page migration resulting from regular references in numerical applications. Loop nests of one and two dimensions (before blocking) with single-level, DOALL-style parallelism are covered. The potential of these transformations is demonstrated experimentally.

  5. Generation of a bubble universe using a negative energy bath

    E-print Network

    Dong-il Hwang; Dong-han Yeom

    2011-06-28

    This paper suggests a model for a bubble universe using buildable false vacuum bubbles. We study the causal structures of collapsing false vacuum bubbles using double-null simulations. False vacuum bubbles violate the null energy condition and emit negative energy along the outgoing direction through semi-classical effects. If there are a few collapsing false vacuum bubbles and they emit negative energy to a certain region, then the region can be approximated by a negative energy bath, which means the region is homogeneously filled by negative energy. If a false vacuum bubble is generated in the negative energy bath and the tension of the bubble effectively becomes negative in the bath, then the bubble can expand and form an inflating bubble universe. This scenario uses a set of assumptions different from those in previous studies because it does not require tunneling to unbuildable bubbles.

  6. Generation of a bubble universe using a negative energy bath

    E-print Network

    Hwang, Dong-il

    2010-01-01

    In this paper, we suggest a model for a bubble universe using buildable false vacuum bubbles. We study causal structures of collapsing false vacuum bubbles using double-null simulations. False vacuum bubbles violate the null energy condition and emit negative energy along the outgoing direction via semi-classical effects. If there are a few collapsing false vacuum bubbles and they emit negative energy to a certain region, then the region can be approximated by a negative energy bath, that means the region is homogeneously filled by negative energy. If a false vacuum bubble is generated in the negative energy bath and the tension of the bubble effectively becomes negative in the bath, then the bubble can expand and form an inflating bubble universe. This scenario is weaker than previous authors' assumptions because we do not require tunneling to unbuildable bubbles. Finally, we summarize potential problems to realize this scenario.

  7. Vendor cited for false PFC savings claim

    SciTech Connect

    Greenstein, I.

    1983-08-29

    A Cynex power factor controller (PFC) vendor claiming a 60% saving was cited by the Better Business Bureau for false advertising after a user survey revealed that savings were only 20% at best. The company plans no future advertising claims, although it insists that 60% savings are possible. The inventor disagrees. (DCK)

  8. Two false dogmas of information science

    Microsoft Academic Search

    Guy A. Marco

    1996-01-01

    Announces and discusses two false beliefs about information science: that there is a distinct discipline of information science; and that librarians need to study it. Finds several definitions of information science to be defective in the sense of what a definition ought to be. Shows that information science is no more than a gathering of findings from communication, computer science

  9. Fate of the false vacuum: Semiclassical theory

    Microsoft Academic Search

    Sidney Coleman

    1977-01-01

    It is possible for a classical field theory to have two homogeneous stable equilibrium states with different energy densities. In the quantum version of the theory, the state of higher-energy density becomes unstable through barrier penetration; it is false vacuum. This is a the first of two papers developing the qualitative and quantitative semiclassical theory of the decay of such

  10. Diseases of Camelina sativa (false flax)

    Microsoft Academic Search

    G. Séguin-Swartz; C. Eynck; R. K. Gugel; S. E. Strelkov; C. Y. Olivier; J. L. Li; H. Klein-Gebbinck; H. Borhan; C. D. Caldwell; K. C. Falk

    2009-01-01

    There is renewed interest in the crucifer Camelina sativa (false flax, camelina, gold of pleasure) as an alternative oilseed crop because of its potential value for food, feed, and industrial applications. This species is adapted to canola-growing areas in many regions of the world and is generally considered to be resistant to many diseases. A review of the literature indicates

  11. Development of the False-Memory Illusion

    ERIC Educational Resources Information Center

    Brainerd, C. J.; Forrest, T. J.; Karibian, D.; Reyna, V. F.

    2006-01-01

    The counterintuitive developmental trend in the Deese-Roediger-McDermott (DRM) illusion (that false-memory responses increase with age) was investigated in learning-disabled and nondisabled children from the 6- to 14-year-old age range. Fuzzy-trace theory predicts that because there are qualitative differences in how younger versus older children…

  12. Infants' Reasoning about Others' False Perceptions

    ERIC Educational Resources Information Center

    Song, Hyun-joo; Baillargeon, Renee

    2008-01-01

    Prior research suggests that children younger than age 3 or 4 do not understand that an agent may be deceived by an object's misleading appearance. The authors asked whether 14.5-month-olds would give evidence in a violation-of-expectation task that they understand that agents may form false perceptions. Infants first watched events in which an…

  13. Item-specific processing reduces false memories.

    PubMed

    McCabe, David P; Presmanes, Alison G; Robertson, Chuck L; Smith, Anderson D

    2004-12-01

    We examined the effect of item-specific and relational encoding instructions on false recognition in two experiments in which the DRM paradigm was used (Deese, 1959; Roediger & McDermott, 1995). Type of encoding (item-specific or relational) was manipulated between subjects in Experiment 1 and within subjects in Experiment 2. Decision-based explanations (e.g., the distinctiveness heuristic) predict reductions in false recognition in between-subjects designs, but not in within-subjects designs, because they are conceptualized as global shifts in decision criteria. Memory-based explanations predict reductions in false recognition in both designs, resulting from enhanced recollection of item-specific details. False recognition was reduced following item-specific encoding instructions in both experiments, favoring a memory-based explanation. These results suggest that providing unique cues for the retrieval of individual studied items results in enhanced discrimination between those studied items and critical lures. Conversely, enhancing the similarity of studied items results in poor discrimination among items within a particular list theme. These results are discussed in terms of the item-specific/ relational framework (Hunt & McDaniel, 1993). PMID:15875978

  14. Experimental investigation of false positive errors in auditory species occurrence surveys.

    PubMed

    Miller, David A W; Weir, Linda A; Mcclintock, Brett T; Grant, Evan H Campbell; Bailey, Larissa L; Simons, Theodore R

    2012-07-01

    False positive errors are a significant component of many ecological data sets, which in combination with false negative errors, can lead to severe biases in conclusions about ecological systems. We present results of a field experiment where observers recorded observations for known combinations of electronically broadcast calling anurans under conditions mimicking field surveys to determine species occurrence. Our objectives were to characterize false positive error probabilities for auditory methods based on a large number of observers, to determine if targeted instruction could be used to reduce false positive error rates, and to establish useful predictors of among-observer and among-species differences in error rates. We recruited 31 observers, ranging in abilities from novice to expert, who recorded detections for 12 species during 180 calling trials (66,960 total observations). All observers made multiple false positive errors, and on average 8.1% of recorded detections in the experiment were false positive errors. Additional instruction had only minor effects on error rates. After instruction, false positive error probabilities decreased by 16% for treatment individuals compared to controls with broad confidence interval overlap of 0 (95% CI:--46 to 30%). This coincided with an increase in false negative errors due to the treatment (26%;--3 to 61%). Differences among observers in false positive and in false negative error rates were best predicted by scores from an online test and a self-assessment of observer ability completed prior to the field experiment. In contrast, years of experience conducting call surveys was a weak predictor of error rates. False positive errors were also more common for species that were played more frequently but were not related to the dominant spectral frequency of the call. Our results corroborate other work that demonstrates false positives are a significant component of species occurrence data collected by auditory methods. Instructing observers to only report detections they are completely certain are correct is not sufficient to eliminate errors. As a result, analytical methods that account for false positive errors will be needed, and independent testing of observer ability is a useful predictor for among-observer variation in observation error rates. PMID:22908721

  15. Experimental investigation of false positive errors in auditory species occurrence surveys

    USGS Publications Warehouse

    Miller, David A.W.; Weir, Linda A.; McClintock, Brett T.; Grant, Evan H. Campbell; Bailey, Larissa L.; Simons, Theodore R.

    2012-01-01

    False positive errors are a significant component of many ecological data sets, which in combination with false negative errors, can lead to severe biases in conclusions about ecological systems. We present results of a field experiment where observers recorded observations for known combinations of electronically broadcast calling anurans under conditions mimicking field surveys to determine species occurrence. Our objectives were to characterize false positive error probabilities for auditory methods based on a large number of observers, to determine if targeted instruction could be used to reduce false positive error rates, and to establish useful predictors of among-observer and among-species differences in error rates. We recruited 31 observers, ranging in abilities from novice to expert, that recorded detections for 12 species during 180 calling trials (66,960 total observations). All observers made multiple false positive errors and on average 8.1% of recorded detections in the experiment were false positive errors. Additional instruction had only minor effects on error rates. After instruction, false positive error probabilities decreased by 16% for treatment individuals compared to controls with broad confidence interval overlap of 0 (95% CI: -46 to 30%). This coincided with an increase in false negative errors due to the treatment (26%; -3 to 61%). Differences among observers in false positive and in false negative error rates were best predicted by scores from an online test and a self-assessment of observer ability completed prior to the field experiment. In contrast, years of experience conducting call surveys was a weak predictor of error rates. False positive errors were also more common for species that were played more frequently, but were not related to the dominant spectral frequency of the call. Our results corroborate other work that demonstrates false positives are a significant component of species occurrence data collected by auditory methods. Instructing observers to only report detections they are completely certain are correct is not sufficient to eliminate errors. As a result, analytical methods that account for false positive errors will be needed, and independent testing of observer ability is a useful predictor for among-observer variation in observation error rates.

  16. The foraging behavior of granivorous rodents and short-term apparent competition among seeds

    Microsoft Academic Search

    Joseph A. Veech

    2001-01-01

    The foraging behavior of a predator species is thought to be the cause of short-term apparent competition among those prey species that share the predator. Short-term apparent competition is the negative indirect effect that one prey species has on another prey species via its effects on predator foraging behavior. In theory, the density-dependent foraging behavior of gra- nivorous rodents and

  17. Spirit Beholds Bumpy Boulder (False Color)

    NASA Technical Reports Server (NTRS)

    2006-01-01

    As NASA's Mars Exploration Rover Spirit began collecting images for a 360-degree panorama of new terrain, the rover captured this view of a dark boulder with an interesting surface texture. The boulder sits about 40 centimeters (16 inches) tall on Martian sand about 5 meters (16 feet) away from Spirit. It is one of many dark, volcanic rock fragments -- many pocked with rounded holes called vesicles -- littering the slope of 'Low Ridge.' The rock surface facing the rover is similar in appearance to the surface texture on the outside of lava flows on Earth.

    Spirit took this false-color image with the panoramic camera on the rover's 810th sol, or Martian day, of exploring Mars (April 13, 2006). This image is a false-color rendering using camera's 753-nanometer, 535-nanometer, and 432-nanometer filters.

  18. The Problem with False Vacuum Higgs Inflation

    E-print Network

    Malcolm Fairbairn; Philipp Grothaus; Robert Hogan

    2014-03-28

    We investigate the possibility of using the only known fundamental scalar, the Higgs, as an inflaton with minimal coupling to gravity. The peculiar appearance of a plateau or a false vacuum in the renormalised effective scalar potential suggests that the Higgs might drive inflation. For the case of a false vacuum we use an additional singlet scalar field, motivated by the strong CP problem, and its coupling to the Higgs to lift the barrier allowing for a graceful exit from inflation by mimicking hybrid inflation. We find that this scenario is incompatible with current measurements of the Higgs mass and the QCD coupling constant and conclude that the Higgs can only be the inflaton in more complicated scenarios.

  19. False beats in coupled piano string unisons

    NASA Astrophysics Data System (ADS)

    Capleton, Brian

    2004-02-01

    The behavior of a unison pair of piano strings coupled by the soundboard bridge, when one string has localized anisotropy in the reactive part of the bridge admittance for a given partial frequency, can be investigated using a theoretical matrix description. The anisotropy can cause what in piano tuning terminology is referred to as ``false beating'' in a partial of the single string. A mathematical model can be used to illustrate how ``mistunings'' between the strings of the unison (measured when the strings are sounding in isolation from each other) may theoretically arise as a consequence of the normal practice in piano tuning, of eliminating or reducing audible beating in the unison when both strings are sounding. ``False beats'' in a single string partial can be ``inherited'' by a partial of the coupled unison's spectrum, and mistunings between the strings can eliminate or reduce the appearance of this inheritance.

  20. True and False Memories in Maltreated Children

    Microsoft Academic Search

    Mark L. Howe; Dante Cicchetti; Sheree L. Toth; Beth M. Cerrito

    2004-01-01

    Differences in basic memory processes between maltreated and nonmaltreated children were examined in an experiment in which middle-socioeconomic-status (SES; N 560), low-SES maltreated (N 548), and low-SES nonmaltreated (N 551) children (ages 5-7, 8-9, and 10-12 years) studied 12 Deese-Roediger-McDermott lists. Using recall and recognition measures, the results showed that both true and false memories increased with age and, contrary

  1. IPSJ SIG Technical Report false sharing

    E-print Network

    Kasahara, Hironori

    IPSJ SIG Technical Report FFT 1 1 1 1 (FFT) LTE FFT FFT false sharing OSCAR 32 256 FFT 8 SH4A RP2 256 FFT 2 1.97 4 3.9 FFT 256 2 1.91 4 3.32 Automatic Parallelization of Small Point FFT on Multicore (FFT) is one of the most frequently used algorihtms in many applications including digital signal

  2. Evaluating promotional claims as false or misleading.

    PubMed

    Brushwood, David B; Knox, Caitlin A; Liu, Wei; Jenkins, Kevin A

    2013-11-01

    In light of the "false or misleading" standard resulting from the recent legal ruling, it can be concluded that a true claim is one that is both factually and analytically true. Factual truth could be based on the accuracy of the information and the sufficiency of the information. Analytical truth could be based on the scientific foundation for the claim and whether the information within the claim is presented in a balanced way. Regarding the assessment of whether a truthful claim is misleading, the evaluator could consider the relevance, consistency, and context of the information. Standards are important in medication use and medication regulation. Health care professionals who must decide whether a claim is truthful and not misleading will rely on guidance from FDA in determining how to evaluate promotional claims. As the court suggested in the case reviewed here, FDA could take the lead and provide guidance "in differentiating between misleading and false promotion, exaggerations and embellishments, and truthful or non-misleading information." Existing FDA regulations provide a foundation for such guidance. The next step for the agency would be to expand existing guidance to specifically describe how an off-label claim can be identified as either false or misleading. PMID:24128969

  3. Apparent Linear Attenuation Coefficients in Phase Contrast X-Ray Tomography

    PubMed Central

    Yan, Aimin; Wu, Xizeng

    2011-01-01

    In the inline phase contrast x-ray tomography the reconstructed apparent linear attenuation coefficient values may be greatly larger than sample’s linear attenuation coefficients or even be negative. In this work we present a general formula to quantitatively relate the apparent linear attenuation coefficient values in cone-beam phase contrast tomography to sample’s linear attenuation coefficients and refractive indices. This formula overcomes the gross inaccuracy of the existing formula in the literature in analyzing high-resolution phase contrast tomography, and it will be useful for correctly interpreting and quantifying the apparent linear attenuation coefficients in cone-beam x-ray phase contrast tomography. PMID:21691420

  4. 27 CFR 478.128 - False statement or representation.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... true False statement or representation. 478.128 Section 478...478.128 False statement or representation. (a) Any person who knowingly makes any false statement or representation in applying for any...

  5. 27 CFR 478.128 - False statement or representation.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... true False statement or representation. 478.128 Section 478...478.128 False statement or representation. (a) Any person who knowingly makes any false statement or representation in applying for any...

  6. Apparent subdiffusion inherent to single particle tracking.

    PubMed Central

    Martin, Douglas S; Forstner, Martin B; Käs, Josef A

    2002-01-01

    Subdiffusion and its causes in both in vivo and in vitro lipid membranes have become the focus of recent research. We report apparent subdiffusion, observed via single particle tracking (SPT), in a homogeneous system that only allows normal diffusion (a DMPC monolayer in the fluid state). The apparent subdiffusion arises from slight errors in finding the actual particle position due to noise inherent in all experimental SPT systems. A model is presented that corrects this artifact, and predicts the time scales after which the effect becomes negligible. The techniques and results presented in this paper should be of use in all SPT experiments studying normal and anomalous diffusion. PMID:12324428

  7. False positive acetaminophen concentrations in patients with liver injury

    PubMed Central

    Polson, Julie; Wians, Frank H.; Orsulak, Paul; Fuller, Dwain; Murray, Natalie G.; Koff, Jonathan M.; Khan, Adil I.; Balko, Jody A.; Hynan, Linda S.; Lee, William M.

    2013-01-01

    Background Acetaminophen toxicity is the most common form of acute liver failure in the U.S. After acetaminophen overdoses, quantitation of plasma acetaminophen can aid in predicting severity of injury. However, recent case reports have suggested that acetaminophen concentrations may be falsely increased in the presence of hyperbilirubinemia. Methods We tested sera obtained from 43 patients with acute liver failure, mostly unrelated to acetaminophen, utilizing 6 different acetaminophen quantitation systems to determine the significance of this effect. In 36 of the 43 samples with bilirubin concentrations ranging from 1.0-61.5 mg/dl no acetaminophen was detectable by gas chromatography-mass spectroscopy. These 36 samples were then utilized to test the performance characteristics of 2 immunoassay and 4 enzymatic-colorimetric methods. Results Three of four colorimetric methods demonstrated ‘detectable’ values for acetaminophen in from 4 to 27 of the 36 negative samples, low concentration positive values being observed when serum bilirubin concentrations exceeded 10 mg/dl. By contrast, the 2 immunoassay methods (EMIT, FPIA) were virtually unaffected. The false positive values obtained were, in general, proportional to the quantity of bilirubin in the sample. However, prepared samples of normal human serum with added bilirubin showed a dose-response curve for only one of the 4 colorimetric assays. Conclusions False positive acetaminophen tests may result when enzymatic-colorimetric assays are used, most commonly with bilirubin concentrations >10 mg/dl, leading to potential clinical errors in this setting. Bilirubin (or possibly other substances in acute liver failure sera) appears to affect the reliable measurement of acetaminophen, particularly with enzymatic-colorimetric assays. PMID:18279672

  8. False discovery rates in spectral identification

    PubMed Central

    2012-01-01

    Automated database search engines are one of the fundamental engines of high-throughput proteomics enabling daily identifications of hundreds of thousands of peptides and proteins from tandem mass (MS/MS) spectrometry data. Nevertheless, this automation also makes it humanly impossible to manually validate the vast lists of resulting identifications from such high-throughput searches. This challenge is usually addressed by using a Target-Decoy Approach (TDA) to impose an empirical False Discovery Rate (FDR) at a pre-determined threshold x% with the expectation that at most x% of the returned identifications would be false positives. But despite the fundamental importance of FDR estimates in ensuring the utility of large lists of identifications, there is surprisingly little consensus on exactly how TDA should be applied to minimize the chances of biased FDR estimates. In fact, since less rigorous TDA/FDR estimates tend to result in more identifications (at higher 'true' FDR), there is often little incentive to enforce strict TDA/FDR procedures in studies where the major metric of success is the size of the list of identifications and there are no follow up studies imposing hard cost constraints on the number of reported false positives. Here we address the problem of the accuracy of TDA estimates of empirical FDR. Using MS/MS spectra from samples where we were able to define a factual FDR estimator of 'true' FDR we evaluate several popular variants of the TDA procedure in a variety of database search contexts. We show that the fraction of false identifications can sometimes be over 10× higher than reported and may be unavoidably high for certain types of searches. In addition, we further report that the two-pass search strategy seems the most promising database search strategy. While unavoidably constrained by the particulars of any specific evaluation dataset, our observations support a series of recommendations towards maximizing the number of resulting identifications while controlling database searches with robust and reproducible TDA estimation of empirical FDR. PMID:23176207

  9. Astronomy Ranking Task: Apparent and Absolute Magnitude

    E-print Network

    Farritor, Shane

    Astronomy Ranking Task: Apparent and Absolute Magnitude Exercise #1 Description: The figure below is equipped with identical headlights. A. Ranking Instructions: Rank the distance (from greatest to least) that each car is from you. Ranking Order: Greatest 1 _______ 2 _______ 3 _______ 4 _______ Least Or

  10. Astronomy Ranking Task: Apparent and Absolute Magnitude

    E-print Network

    Farritor, Shane

    Astronomy Ranking Task: Apparent and Absolute Magnitude Exercise #3 Description: The figure below shows five stars (A - E) as they appear in the night sky from Earth. The absolute magnitude number: ____________________________________________________________________________ ____________________________________________________________________________ ____________________________________________________________________________ ____________________________________________________________________________ D. Ranking Instructions: Rank the absolute magnitude number (from greatest to least) of each star (A

  11. The dynamic analysis of apparent contours

    Microsoft Academic Search

    Roberto Cipolla; Andrew Blake

    1990-01-01

    The authors develop previous theories of the analysis of deformation of apparent contours under viewer motion. Earlier results showing how surface curvature can be inferred from acceleration of image features are generalized for arbitrary viewer motion and perspective projection. It is shown that relative image acceleration, based on parallax measurements, is robust to uncertainties in robot motion. The theory has

  12. False belief in infancy: a fresh look.

    PubMed

    Heyes, Cecilia

    2014-09-01

    Can infants appreciate that others have false beliefs? Do they have a theory of mind? In this article I provide a detailed review of more than 20 experiments that have addressed these questions, and offered an affirmative answer, using nonverbal 'violation of expectation' and 'anticipatory looking' procedures. Although many of these experiments are both elegant and ingenious, I argue that their results can be explained by the operation of domain-general processes and in terms of 'low-level novelty'. This hypothesis suggests that the infants' looking behaviour is a function of the degree to which the observed (perceptual novelty) and remembered or expected (imaginal novelty) low-level properties of the test stimuli - their colours, shapes and movements - are novel with respect to events encoded by the infants earlier in the experiment. If the low-level novelty hypothesis is correct, research on false belief in infancy currently falls short of demonstrating that infants have even an implicit theory of mind. However, I suggest that the use of two experimental strategies - inanimate control procedures, and self-informed belief induction - could be used in combination with existing methods to bring us much closer to understanding the evolutionary and developmental origins of theory of mind. PMID:24666559

  13. False belief understanding in maltreated children.

    PubMed

    Cicchetti, Dante; Rogosch, Fred A; Maughan, Angeline; Toth, Sheree L; Bruce, Jacqueline

    2003-01-01

    False belief understanding was investigated in maltreated (N = 203), low socioeconomic status (SES) nonmaltreated (N = 143), and middle SES nonmaltreated (N = 172) 3- to 8-year-old children. Contrasts among the three groups provided an opportunity to examine the impact of family contextual influences on theory of mind development. Specifically, child maltreatment served as an "experiment of nature" in order to elucidate theory of mind abilities. Two false belief tasks and language assessments were administered. Among children with a verbal mental age of 49 months or greater, maltreatment was related to delays in the development of theory of mind, beyond the influence of chronological age and SES. The occurrence of maltreatment during the toddler period, onset during the toddler years, and physical abuse were features of maltreatment associated with delay in the development of theory of mind. Findings are discussed in terms of the influence of harsh caregiving on the development of theory of mind. Implications for the understanding of normal developmental processes are highlighted. PMID:14984138

  14. Quantum efficiency and false positive rate

    PubMed Central

    Hallett, P. E.

    1969-01-01

    1. This paper presents an analysis of the efficiency of performance at the absolute threshold of human vision. The data are from the same series as the previous papers (Hallett, 1969b, c) and consist of frequency-of-seeing curves, thresholds, false positive rates and equivalent background measurements, accumulated as small samples over a number of days. 2. Quantum efficiency is defined here as the ratio of the thresholds of an ideal and a real detector performing the same task with the same sampling error. This avoids the problem as to whether the frequency-of-seeing curve of the real detector is exactly a Poisson sum or not. 3. The long-term quantum efficiency can be low (about 0·04) as a result of drifts in the mean threshold. 4. The average short-term quantum efficiency is in the region of 0·1, which is roughly the physiological limit set by Rushton's (1956b) measurements of rhodopsin density in the living rods. If this is correct, then the absorption of a quantum, and not the bleaching of a rhodopsin molecule, is sufficient for the generation of a neural event. 5. Application of a simple signal/noise theory to the data gives solutions close to those suggested by Barlow (1956) and shows that false positives almost invariably arise from errors subsequent to the signal/noise decision process. PMID:5784295

  15. True versus False Positives and Negatives on the "Modified Checklist for Autism in Toddlers"

    ERIC Educational Resources Information Center

    Matson, Johnny L.; Kozlowski, Alison M.; Fitzgerald, Mary E.; Sipes, Megan

    2013-01-01

    Given the importance of early intervention services for children with autism spectrum disorders (ASD), early diagnosis of children is critical. At present, several ASD screeners exist for young children, with the "Modified Checklist for Autism in Toddlers" ("M-CHAT") being one of the most widely researched. While the "M-CHAT" has good sensitivity…

  16. Oligosymptomatic neurosyphilis with false negative CSF-VDRL in HIV-infected individuals?

    PubMed

    Malessa, R; Agelink, M W; Hengge, U; Mertins, L; Gastpar, M; Brockmeyer, N H

    1996-03-19

    The true prevalence of neurosyphilis in HIV-infection is unknown, since a sufficiently sensitive and specific test is lacking. In a prospective study we found reactive serum TPHA and FTA-ABS IgG tests in 95 (31%) of 307 HIV-infected patients. Three of 11 patients with latent syphilis revealed reactive CSF-VDRL tests, six others only demonstrated CSF abnormalities. Resolution of CSF abnormalities during a six month follow up after high dose antibiotic therapy led to the diagnosis of oligosymptomatic or asymptomatic neurosyphilis in all nine patients. Thus, the specificity of the CSF-VDRL was 100%, but the sensitivity was only 33%. The overall prevalence of neurosyphilis was 2.9%, increasing to 9.5% in patients with a reactive serum TPHA. Our study emphasizes the importance of antibiotic therapy for presumptive neurosyphilis in HIV-infected patients with latent syphilis and CSF abnormalities but nonreactive CSF-VDRL tests, even if they are neurologically asymptomatic or present with complaints inconclusive of neurosyphilis. PMID:9367943

  17. False-negative magnetic resonance imaging in early stage of Legg-Calve-Perthes disease

    SciTech Connect

    Elsig, J.P.; Exner, G.U.; von Schulthess, G.K.; Weitzel, M.

    1989-03-01

    We report a 7-year 6-month-old boy with Legg-Calve-Perthes (LCP) disease in whom a magnetic resonance imaging (MRI) was normal during the early symptomatic phase when the /sup 99m/Tc bone scintigraphy showed segmental hypoperfusion of the femoral head suggestive of bone infarction. Only later in the disease did the MRI also show the typical changes of LCP. The follow-up on this patient with bilateral disease leaves no doubt about the diagnosis of LCP. This sequence of a positive scintigram before positive MRI findings may be the exception, but it is important to realize that MRI is not always the most sensitive way to diagnose or exclude LCP as suggested hitherto by the literature.

  18. Reducing False Negative Reads in RFID Data Streams Using an Adaptive Sliding-Window Approach

    PubMed Central

    Massawe, Libe Valentine; Kinyua, Johnson D. M.; Vermaak, Herman

    2012-01-01

    Unreliability of the data streams generated by RFID readers is among the primary factors which limit the widespread adoption of the RFID technology. RFID data cleaning is, therefore, an essential task in the RFID middleware systems in order to reduce reading errors, and to allow these data streams to be used to make a correct interpretation and analysis of the physical world they are representing. In this paper we propose an adaptive sliding-window based approach called WSTD which is capable of efficiently coping with both environmental variation and tag dynamics. Our experimental results demonstrate the efficacy of the proposed approach. PMID:22666027

  19. Urine testing for norcodeine, norhydrocodone, and noroxycodone facilitates interpretation and reduces false negatives

    Microsoft Academic Search

    Edward J. Cone; Anne Zichterman; Rebecca Heltsley; David L. Black; Beverly Cawthon; Tim Robert; Frank Moser; Yale H. Caplan

    2010-01-01

    Urine drug testing of pain patients provides objective information to health specialists regarding patient compliance, diversion, and concurrent illicit drug use. Interpretation of urine test results for semi-synthetic opiates can be difficult because of complex biotransformations of parent drug to metabolites that are also available commercially and may be abused. Normetabolites such as norcodeine, norhydrocodone and noroxycodone are unique metabolites

  20. False positive head-up tilt

    Microsoft Academic Search

    Fabio M Leonelli; Ke Wang; Joyce M Evans; Abhijit R Patwardhan; Michael G Ziegler; Andrea Natale; Charles S Kim; Kathleen Rajikovich; Charles F Knapp

    2000-01-01

    OBJECTIVESThis study examined differences in mechanisms of head-up tilt (HUT)-induced syncope between normal controls and patients with neurocardiogenic syncope.BACKGROUNDA variable proportion of normal individuals experience syncope during HUT. Differences in the mechanisms of HUT-mediated syncope between this group and patients with neurocardiogenic syncope have not been elucidated.METHODSA 30-min 80° HUT was performed in eight HUT-negative volunteers (Group I), eight HUT-positive

  1. 47 CFR 80.1114 - False distress alerts.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ...2012-10-01 false False distress alerts. 80.1114 Section 80.1114...Communications § 80.1114 False distress alerts. The provisions of §§ 80.334 and 80.335 apply to false distress alerts. [68 FR 46980, Aug. 7,...

  2. 47 CFR 80.334 - False distress alerts.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ...2012-10-01 2012-10-01 false False distress alerts. 80.334 Section 80.334 Telecommunication...and Safety Procedures § 80.334 False distress alerts. A distress alert is false if it was transmitted without any...

  3. 47 CFR 80.1114 - False distress alerts.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ...2013-10-01 false False distress alerts. 80.1114 Section 80.1114...Communications § 80.1114 False distress alerts. The provisions of §§ 80.334 and 80.335 apply to false distress alerts. [68 FR 46980, Aug. 7,...

  4. 47 CFR 80.334 - False distress alerts.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ...2011-10-01 2011-10-01 false False distress alerts. 80.334 Section 80.334 Telecommunication...and Safety Procedures § 80.334 False distress alerts. A distress alert is false if it was transmitted without any...

  5. 47 CFR 80.1114 - False distress alerts.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ...2011-10-01 false False distress alerts. 80.1114 Section 80.1114...Communications § 80.1114 False distress alerts. The provisions of §§ 80.334 and 80.335 apply to false distress alerts. [68 FR 46980, Aug. 7,...

  6. 47 CFR 80.1114 - False distress alerts.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ...2010-10-01 false False distress alerts. 80.1114 Section 80.1114...Communications § 80.1114 False distress alerts. The provisions of §§ 80.334 and 80.335 apply to false distress alerts. [68 FR 46980, Aug. 7,...

  7. 47 CFR 80.334 - False distress alerts.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ...2010-10-01 2010-10-01 false False distress alerts. 80.334 Section 80.334 Telecommunication...and Safety Procedures § 80.334 False distress alerts. A distress alert is false if it was transmitted without any...

  8. 47 CFR 80.334 - False distress alerts.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ...2013-10-01 2013-10-01 false False distress alerts. 80.334 Section 80.334 Telecommunication...and Safety Procedures § 80.334 False distress alerts. A distress alert is false if it was transmitted without any...

  9. Opportunity View of 'Gilbert' Layer (False Color)

    NASA Technical Reports Server (NTRS)

    2008-01-01

    This view from NASA's Mars Exploration Rover Opportunity shows bedock within a stratigraphic layer informally named 'Gilbert,' which is the rover's next target after completing an examination of three stratigtaphic layers forming a bright band around the inside of Victoria Crater. The rover will descend deeper into the crater to reach the Gilbert layer.

    Opportunity used its panoramic camera (Pancam) to capture this image with low-sun angle at a local solar time of 3:30 p.m. during the rover's 1,429th Martian day, of sol (Jan. 31, 2008).

    This view combines separate images taken through the Pancam filters centered on wavelengths of 753 nanometers, 535 nanometers and 432 nanometers. It is presented in a false-color stretch to bring out subtle color differences in the scene.

  10. Opportunity View of 'Lyell' Layer (False Color)

    NASA Technical Reports Server (NTRS)

    2008-01-01

    This view from NASA's Mars Exploration Rover Opportunity shows bedrock within a stratigraphic layer informally named 'Lyell,' which is the lowermost of three layers the rover has examined at a bright band around the inside of Victoria Crater.

    Opportunity used its panoramic camera (Pancam) to capture this image with low-sun angle at a local solar time of 3:21 p.m. during the rover's 1,433rd Martian day, of sol (Feb. 4, 2008).

    This view combines separate images taken through the Pancam filters centered on wavelengths of 753 nanometers, 535 nanometers and 432 nanometers. It is presented in a false-color stretch to bring out subtle color differences in the scene.

  11. View from Spirit's Overwintering Position (False Color)

    NASA Technical Reports Server (NTRS)

    2008-01-01

    NASA's Mars Exploration Rover Spirit has this view northward from the position at the north edge of the 'Home Plate' plateau where the rover will spend its third Martian winter.

    Husband Hill is on the horizon. The dark area in the middle distance is 'El Dorado' sand dune field.

    Spirit used its panoramic camera (Pancam) to capture this image during the rover's 1,448th Martian day, of sol (Jan. 29, 2008).

    This view combines separate images taken through the Pancam filters centered on wavelengths of 753 nanometers, 535 nanometers and 432 nanometers. It is presented in a false-color stretch to bring out subtle color differences in the scene.

  12. Remembering, imagining, false memories & personal meanings.

    PubMed

    Conway, Martin A; Loveday, Catherine

    2015-05-01

    The Self-Memory System encompasses the working self, autobiographical memory and episodic memory. Specific autobiographical memories are patterns of activation over knowledge structures in autobiographical and episodic memory brought about by the activating effect of cues. The working self can elaborate cues based on the knowledge they initially activate and so control the construction of memories of the past and the future. It is proposed that such construction takes place in the remembering-imagining system - a window of highly accessible recent memories and simulations of near future events. How this malfunctions in various disorders is considered as are the implication of what we term the modern view of human memory for notions of memory accuracy. We show how all memories are to some degree false and that the main role of memories lies in generating personal meanings. PMID:25592676

  13. Apparent dispersion in transient groundwater flow

    Microsoft Academic Search

    Daniel J. Goode; Leonard F. Konikow

    1990-01-01

    This paper investigates the effects of large-scale temporal velocity fluctuations, particularly changes in the direction of flow, on solute spreading in a two-dimensional aquifer. Relations for apparent longitudinal and transverse dispersivity are developed through an analytical solution for dispersion in a fluctuating, quasi-steady uniform flow field, in which storativity is zero. For transient flow, spatial moments are evaluated from numerical

  14. Apparent oxygen solubility in refractory carbides

    Microsoft Academic Search

    D. Gozzi; M. Montozzi; P. L. Cignini

    1999-01-01

    The occurrence of an apparent solubility of oxygen in polycrystalline NbC, TiC, VC and ZrC is discussed. This is shown by experiments in which the oxygen consumed by the sample is directly measured as a function of temperature in an argon stream at 1.6 bar (rel) where the oxygen partial pressure was as low as 0.8 Pa. The parameter ?,

  15. Rubber friction on (apparently) smooth lubricated surfaces

    E-print Network

    M. Mofidi; B. Prakash; B. N. J. Persson; O. Albohl

    2007-10-18

    We study rubber sliding friction on hard lubricated surfaces. We show that even if the hard surface appears smooth to the naked eye, it may exhibit short wavelength roughness, which may give the dominant contribution to rubber friction. That is, the observed sliding friction is mainly due to the viscoelastic deformations of the rubber by the substrate surface asperities. The presented results are of great importance for rubber sealing and other rubber applications involving (apparently) smooth surfaces.

  16. Apparent Solar Tornado-Like Prominences

    NASA Astrophysics Data System (ADS)

    Panasenco, Olga; Martin, Sara F.; Velli, Marco

    2014-02-01

    Recent high-resolution observations from the Solar Dynamics Observatory (SDO) have reawakened interest in the old and fascinating phenomenon of solar tornado-like prominences. This class of prominences was first introduced by Pettit ( Astrophys. J. 76, 9, 1932), who studied them over many years. Observations of tornado prominences similar to the ones seen by SDO had already been documented by Secchi ( Le Soleil, 1877). High-resolution and high-cadence multiwavelength data obtained by SDO reveal that the tornado-like appearance of these prominences is mainly an illusion due to projection effects. We discuss two different cases where prominences on the limb might appear to have a tornado-like behavior. One case of apparent vortical motions in prominence spines and barbs arises from the (mostly) 2D counterstreaming plasma motion along the prominence spine and barbs together with oscillations along individual threads. The other case of apparent rotational motion is observed in a prominence cavity and results from the 3D plasma motion along the writhed magnetic fields inside and along the prominence cavity as seen projected on the limb. Thus, the "tornado" impression results either from counterstreaming and oscillations or from the projection on the plane of the sky of plasma motion along magnetic-field lines, rather than from a true vortical motion around an (apparent) vertical or horizontal axis. We discuss the link between tornado-like prominences, filament barbs, and photospheric vortices at their base.

  17. Apparent Acceleration and AN Alternative Concordance from Causal Backreaction

    NASA Astrophysics Data System (ADS)

    Bochner, Brett

    2015-01-01

    A phenomenological formalism is presented in which the apparent acceleration of the universe is generated by cosmic structure formation, without resort to Dark Energy, modifications to gravity, or a local void. The observed acceleration results from the combined effect of innumerable local perturbations due to individually virializing systems, overlapping together in a smoothly-inhomogeneous adjustment of the FRW metric, in a process governed by the causal flow of inhomogeneity information outward from each clumped system. After noting how common arguments claiming to limit backreaction are physically unrealistic, models are presented which fit the supernova luminosity distance data essentially as well as ?CDM, while bringing several important cosmological parameters to a new Concordance. These goals are all achieved with a second-generation version of our formalism that accounts for the negative feedback of Causal Backreaction upon itself due to the slowed propagation of gravitational inhomogeneity information.

  18. A Case of Apparent Contact Dermatitis Caused by Toxocara Infection

    PubMed Central

    Makrì, Eleni; Losappio, Laura

    2014-01-01

    Infection from Toxocara species may give rise to a large array of clinical symptoms, including apparent manifestations of allergy such as asthma, urticaria/angioedema, and dermatitis. We report a case, thus far not described, of contact dermatitis attributed to nickel allergy but caused by Toxocara infection. The patient was a 53-year-old woman presenting from 10 years a dermatitis affecting head, neck, and thorax. Patch tests initially performed gave a positive result to nickel, but avoidance of contact with nickel did not result in recovery. The patient referred to our Allergy Service in 2010 because of dermatitis to feet. Patch testing confirmed the positive result for nickel, but expanding the investigation a positive result for IgG antibodies to Toxocara was detected by Western blotting and ELISA. Treatment with mebendazole achieved immediate efficacy on feet dermatitis. Then, two courses of treatment with albendazole resulted in complete regression of dermatitis accompanied by development of negative ELISA and Western blotting for Toxocara antibodies. This report adds another misleading presentation of Toxocara infection as apparent contact dermatitis caused by nickel and suggests bearing in mind, in cases of contact dermatitis not responding to avoidance of the responsible hapten and to medical treatment, the possible causative role of Toxocara. PMID:25580310

  19. Coaching, Truth Induction, and Young Maltreated Children's False Allegations and False Denials

    ERIC Educational Resources Information Center

    Lyon, Thomas D.; Malloy, Lindsay C.; Quas, Jodi A.; Talwar, Victoria A.

    2008-01-01

    This study examined the effects of coaching (encouragement and rehearsal of false reports) and truth induction (a child-friendly version of the oath or general reassurance about the consequences of disclosure) on 4- to 7-year-old maltreated children's reports (N = 198). Children were questioned using free recall, repeated yes-no questions, and…

  20. False-color composite of Oetztal, Austria

    NASA Technical Reports Server (NTRS)

    1994-01-01

    This image is a false-color composite of Oetztal, Austria located in the Central Alps centered at 46.8 degrees north latitude, 10.70 degrees east longitude, at the border between Switzerland (top), Italy (left) and Austria (right and bottom). The area shown is 50 kilometers (30 miles) south of Inssbruck, Austria. This image was acquired by the Spaceborne Imaging Radar-C/X-band Synthetic Aperature Radar (SIR-C/X-SAR) flying on the Space Shuttle Endeavour on its 14th orbit. Approximately one quarter of this image is covered by glaciers, the largest of which, Gepatschferner, is visible as a triangular yellow patch in the center of the scene. The blue areas are lakes (Gepatsch dam at center right; Lake Muta at top right) and glacier ice. The yellow areas are slopes facing the radar and areas of dry snow. Purple corresponds to slopes facing away from the radar. Yellow in the valley bottom corresponds to tree covered areas. The Jet Propulsion Laboratory alternative photo number is P-43890.

  1. Possible and False Biomarkers from Space

    NASA Technical Reports Server (NTRS)

    Bernstein, Max P.

    2004-01-01

    The Search for life in the Solar System is one of NASA's main goals for the coming decade. We may never observe alien life directly; we or our robotic craft may always be removed from it by many years, or meters of crust. If we do find evidence of Life elsewhere in the Solar System it will probably be in form of chemical biomarkers, quintessentially biological molecules that indicate the presence of micro-organisms. What molecules would be truly indicative of alien life? Chlorophyll fragments, which are often used by geochemists are probably far too specific. Simpler molecules, such as fatty acids, amino acids and nucleo-bases might seem to be biomarkers, but they can form non-biotically in space. Alkyl substituted aromatics in ALH 84001 have been invoked as biomarkers, but they are not strong evidence in and of themselves. Understanding the range of nonbiological organic molecules which could act as false biomarkers in space is a prerequisite for any reasonable search for true biomarkers on other worlds. When simple organics arrive at the surface of a body like Europa, either from below or from space, how long do they survive and what do they make? How can we distinguish these from real biomarkers? In this talk I will present some ideas about what might be useful qualities to consider in a potential biomarker, and will ask for advice from the attendant geochemists.

  2. Avoiding the False Peaks in Correlation Discrimination

    SciTech Connect

    Awwal, A S

    2009-07-31

    Fiducials imprinted on laser beams are used to perform video image based alignment of the 192 laser beams in the National Ignition Facility (NIF) of Lawrence Livermore National Laboratory. In many video images, matched filtering is used to detect the location of these fiducials. Generally, the highest correlation peak is used to determine the position of the fiducials. However, when the signal to-be-detected is very weak compared to the noise, this approach totally breaks down. The highest peaks act as traps for false detection. The active target images used for automatic alignment in the National Ignition Facility are examples of such images. In these images, the fiducials of interest exhibit extremely low intensity and contrast, surrounded by high intensity reflection from metallic objects. Consequently, the highest correlation peaks are caused by these bright objects. In this work, we show how the shape of the correlation is exploited to isolate the valid matches from hundreds of invalid correlation peaks, and therefore identify extremely faint fiducials under very challenging imaging conditions.

  3. Earth - False Color Mosaic of the Andes

    NASA Technical Reports Server (NTRS)

    1992-01-01

    This false-color mosaic of the central part of the Andes mountains of South America (70 degrees west longitude, 19 degrees south latitude) is made up of 42 images acquired by the Galileo spacecraft from an altitude of about 25,000 kilometers (15,000 miles). A combination of visible (green) and near-infrared (0.76 and 1.0-micron) filters was chosen for this view to separate regions with distinct vegetation and soil types. The mosaic shows the area where Chile, Peru and Bolivia meet. The Pacific Coast appears at the left of the image-- Galileo captured this view as it traveled west over the Pacific Ocean, looking back at the Andes. Lakes Titicaca and Poopo are nearly black patches at the top and center, respectively; a large light-blue area below and to the left of Lake Poopo is Salar de Uyuni, a dry salt lake some 120 kilometers (75 miles) across. These lakes lie in the Altiplano, a region between the western and eastern Andes, which are covered by clouds. The vegetation-bearing Gran Chaco plains east of the Andes appear pale green. Light-blue patches in the mountains to the north are glaciers.

  4. An Apparent Relationship Between Locoism and Lathyrism

    PubMed Central

    Keeler, Richard F.; James, Lynn F.; Binns, Wayne; Shupe, James L.

    1967-01-01

    An apparent relationship between locoism and lathyrism was investigated. Similarities reported in the literature in botanical relationship, signs produced in affected animals, and chemical characteristics were noted. It was demonstrated that the known lathyrogens, aminoacetonitrile and ?, ?-diaminobutyric acid, as well as an extract from the loco plant (expected to contain lathyrogens if present in the plant) produced many of the abortive, teratogenic and neurologic effects and signs evident in animals in true locoism. Preliminary assay of extracts from the plant suggested the presence of lathyrogens in the loco plant. ImagesFig. 1.Fig. 2.Fig. 3.Fig. 5.Fig. 6.Fig. 7. PMID:4229933

  5. Humoural immune response and pathological analysis in patients with false immune diagnosis of cystic echinococcosis

    PubMed Central

    Chen, X; Zhang, J; Feng, X; Chen, X; Yin, S; Wen, H; Zheng, S

    2014-01-01

    The patients with false immune diagnosis of hydatid disease were investigated for the humoural immune response to analyse the possible reasons and mechanism leading to false immune diagnosis. Two hundred and thirty-nine patients with nature-unknown cysts and 30 healthy controls were detected by immunological assays (four hydatid antigen-based immunogold filtration assay and enzyme-linked immune absorbent assay) and ultrasound. Sensitivity of and specificity of immunological assay and ultrasound were calculated, respectively. The serological diagnosis was compared with surgical pathology to screen the patients with false immune diagnosis for the immunoglobulin measurement and pathological analysis. The history and cyst characteristics were also reviewed. The results indicate the immunoglobulin has little influence on false immunodiagnosis. The false-negative immunodiagnosis was caused by the cysts' inactive status while the false positive caused by previous rupture, antigen cross-reaction. The clinical diagnosis of cystic echinococcosis requires a combination of immunodiagnosis and ultrasonography, which is the necessary complementary confirmation. PMID:24372157

  6. Natural and False Color Views of Europa

    NASA Technical Reports Server (NTRS)

    1996-01-01

    This image shows two views of the trailing hemisphere of Jupiter's ice-covered satellite, Europa. The left image shows the approximate natural color appearance of Europa. The image on the right is a false-color composite version combining violet, green and infrared images to enhance color differences in the predominantly water-ice crust of Europa. Dark brown areas represent rocky material derived from the interior, implanted by impact, or from a combination of interior and exterior sources. Bright plains in the polar areas (top and bottom) are shown in tones of blue to distinguish possibly coarse-grained ice (dark blue) from fine-grained ice (light blue). Long, dark lines are fractures in the crust, some of which are more than 3,000 kilometers (1,850 miles) long. The bright feature containing a central dark spot in the lower third of the image is a young impact crater some 50 kilometers (31 miles) in diameter. This crater has been provisionally named 'Pwyll' for the Celtic god of the underworld.

    Europa is about 3,160 kilometers (1,950 miles) in diameter, or about the size of Earth's moon. This image was taken on September 7, 1996, at a range of 677,000 kilometers (417,900 miles) by the solid state imaging television camera onboard the Galileo spacecraft during its second orbit around Jupiter. The image was processed by Deutsche Forschungsanstalt fuer Luftund Raumfahrt e.V., Berlin, Germany.

    The Jet Propulsion Laboratory, Pasadena, CA, manages the mission for NASA's Office of Space Science, Washington, DC.

    This image and other images and data received from Galileo are posted on the Galileo mission home page on the World Wide Web at http://galileo.jpl.nasa.gov. Background information and educational context for the images can be found at http://www.jpl.nasa.gov/galileo/sepo

  7. Constraining Oxygen False Positives in Planetary Atmospheres

    NASA Astrophysics Data System (ADS)

    Harman, C. E.; Schottelkotte, J. C.; Kasting, J. F.

    2014-03-01

    Oxygen (O2) and ozone (O3) in the present Earth's atmosphere are byproducts of oxygenic photosynthesis coupled with organic carbon burial. On Earth, no known abiotic surface process would be able to generate such an atmosphere, and by extension, lifeless exoplanets are expected to be devoid of O2. As a result, molecular oxygen and ozone are often seen as convincing signposts for life. Recently, however, a number of authors have demonstrated the abiotic generation of molecular oxygen in a planetary atmosphere, either under oxidizing conditions (Hu et al., 2013) or around an M star (Tian et al., 2013). This èfalse positive', if verified, would remove oxygen and ozone from an already short list of easily detectable biosignatures. We explore oxygen false positives with our 1-D photochemical model, updated from Segura et al. (2007). Preliminary results show that if water vapor photolysis longward of ~200 nm is neglected, substantial amounts of CO and O2 can build up in the lower part of the atmosphere. Additionally, the ultimate fate of CO and O2 produced in such atmospheres is strongly dependent on the imposed lower boundary condition, with low depositional velocities corresponding to higher mixing ratios in the lower atmosphere. The deposition velocity of a gas depends on it dissolved concentration, however, and so one needs to consider the chemistry of these gases in solution. Ongoing work seeks to test the conclusions of Tian et al., (2013) by exploring this dependence on ocean chemistry and by including spectra from AD Leo (an active M-dwarf, used by Domagal-Goldman et al., (2011)) to compare with the M-dwarf spectra used by Tian et al.

  8. 'Lyell' Panorama inside Victoria Crater (False Color)

    NASA Technical Reports Server (NTRS)

    2008-01-01

    During four months prior to the fourth anniversary of its landing on Mars, NASA's Mars Exploration Rover Opportunity examined rocks inside an alcove called 'Duck Bay' in the western portion of Victoria Crater. The main body of the crater appears in the upper right of this stereo panorama, with the far side of the crater lying about 800 meters (half a mile) away. Bracketing that part of the view are two promontories on the crater's rim at either side of Duck Bay. They are 'Cape Verde,' about 6 meters (20 feet) tall, on the left, and 'Cabo Frio,' about 15 meters (50 feet) tall, on the right. The rest of the image, other than sky and portions of the rover, is ground within Duck Bay.

    Opportunity's targets of study during the last quarter of 2007 were rock layers within a band exposed around the interior of the crater, about 6 meters (20 feet) from the rim. Bright rocks within the band are visible in the foreground of the panorama. The rover science team assigned informal names to three subdivisions of the band: 'Steno,' 'Smith,' and 'Lyell.'

    This view combines many images taken by Opportunity's panoramic camera (Pancam) from the 1,332nd through 1,379th Martian days, or sols, of the mission (Oct. 23 to Dec. 11, 2007). Images taken through Pancam filters centered on wavelengths of 753 nanometers, 535 nanometers and 432 nanometers were mixed to produce this view, which is presented in a false-color stretch to bring out subtle color differences in the scene. Some visible patterns in dark and light tones are the result of combining frames that were affected by dust on the front sapphire window of the rover's camera.

    Opportunity landed on Jan. 25, 2004, Universal Time, (Jan. 24, Pacific Time) inside a much smaller crater about 6 kilometers (4 miles) north of Victoria Crater, to begin a surface mission designed to last 3 months and drive about 600 meters (0.4 mile).

  9. Spirit's West Valley Panorama (False Color)

    NASA Technical Reports Server (NTRS)

    2008-01-01

    NASA'S Mars Exploration Rover Spirit captured this westward view from atop a low plateau where Sprit spent the closing months of 2007.

    After several months near the base of the plateau called 'Home Plate' in the inner basin of the Columbia Hills range inside Gusev Crater, Spirit climbed onto the eastern edge of the plateau during the rover's 1,306th Martian day, or sol, (Sept. 5, 2007). It examined rocks and soils at several locations on the southern half of Home Plate during September and October. It was perched near the western edge of Home Plate when it used its panoramic camera (Pancam) to take the images used in this view on sols 1,366 through 1,369 (Nov. 6 through Nov. 9, 2007). With its daily solar-energy supply shrinking as Martian summer turned to fall, Spirit then drove to the northern edge of Home Plate for a favorable winter haven. The rover reached that northward-tilting site in December, in time for the fourth Earth-year anniversary of its landing on Mars. Spirit reached Mars on Jan. 4, 2004, Universal Time (Jan. 3, 2004, Pacific Standard Time). It landed at a site at about the center of the horizon in this image.

    This panorama covers a scene spanning left to right from southwest to northeast. The western edge of Home Plate is in the foreground, generally lighter in tone than the more distant parts of the scene. A rock-dotted hill in the middle distance across the left third of the image is 'Tsiolkovski Ridge,' about 30 meters or 100 feet from the edge of Home Plate and about that same distance across. A bump on the horizon above the left edge of Tsiolkovski Ridge is 'Grissom Hill,' about 8 kilometers or 5 miles away. At right, the highest point of the horizon is 'Husband Hill,' to the north and about 800 meters or half a mile away.

    This view combines separate images taken through Pancam filters centered on wavelengths of 753 nanometers, 535 nanometers and 432 nanometers. It is presented in a false-color stretch to bring out subtle color differences in the scene.

  10. Panorama from 'Cape Verde' (False Color)

    NASA Technical Reports Server (NTRS)

    2007-01-01

    NASA's Mars Exploration Rover Opportunity captured this vista of 'Victoria Crater' from the viewpoint of 'Cape Verde,' one of the promontories that are part of the scalloped rim of the crater. Opportunity drove onto Cape Verde shortly after arriving at the rim of Victoria in September 2006. The view combines hundreds of exposures taken by the rover's panoramic camera (Pancam). The camera began taking the component images during Opportunity's 970th Martian day, or sol, on Mars (Oct. 16, 2006). Work on the panorama continued through the solar conjunction period, when Mars was nearly behind the sun from Earth's perspective and communications were minimized. Acquisition of images for this panorama was completed on Opportunity's 991st sol (Nov. 7, 2006).

    The top of Cape Verde is in the immediate foreground at the center of the image. To the left and right are two of the more gradually sloped bays that alternate with the cliff-faced capes or promontories around the rim of the crater. 'Duck Bay,' where Opportunity first reached the rim, is to the right. Beyond Duck Bay counterclockwise around the rim, the next promontory is 'Cabo Frio,' about 150 meters (500 feet) from the rover. On the left side of the panorama is 'Cape St. Mary,' the next promontory clockwise from Cape Verde and about 40 meters (130 feet) from the rover. The vantage point atop Cape Verde offered a good view of the rock layers in the cliff face of Cape St. Mary, which is about 15 meters or 50 feet tall. By about two weeks after the Pancam finished collecting the images for this panorama, Opportunity had driven to Cape St. Mary and was photographing Cape Verde's rock layers.

    The far side of the crater lies about 800 meters (half a mile) away, toward the southeast.

    This view combines images taken through three of the Pancam's filters, admitting light with wavelengths centered at 750 nanometers (near infrared), 530 nanometers (green) and 430 nanometers (violet). It is presented in false color to emphasize differences among materials in the rocks and soils.

  11. Channel with Island in False Color

    NASA Technical Reports Server (NTRS)

    2004-01-01

    [figure removed for brevity, see original site]

    Released 29 March 2004

    The Odyssey spacecraft has completed a full Mars year of observations of the red planet. For the next several weeks the Image of the Day will look back over this first mars year. It will focus on four themes: 1) the poles - with the seasonal changes seen in the retreat and expansion of the caps; 2) craters - with a variety of morphologies relating to impact materials and later alteration, both infilling and exhumation; 3) channels - the clues to liquid surface flow; and 4) volcanic flow features. While some images have helped answer questions about the history of Mars, many have raised new questions that are still being investigated as Odyssey continues collecting data as it orbits Mars.

    This false color image shows part of the Apsus Vallis region. It was collected February 2, 2003 during northern summer season. The local time is 5pm. The image shows a typical channel formation with island created in it.

    Image information: VIS instrument. Latitude 35.1, Longitude 135 East (225 West). 19 meter/pixel resolution.

    Note: this THEMIS visual image has not been radiometrically nor geometrically calibrated for this preliminary release. An empirical correction has been performed to remove instrumental effects. A linear shift has been applied in the cross-track and down-track direction to approximate spacecraft and planetary motion. Fully calibrated and geometrically projected images will be released through the Planetary Data System in accordance with Project policies at a later time.

    NASA's Jet Propulsion Laboratory manages the 2001 Mars Odyssey mission for NASA's Office of Space Science, Washington, D.C. The Thermal Emission Imaging System (THEMIS) was developed by Arizona State University, Tempe, in collaboration with Raytheon Santa Barbara Remote Sensing. The THEMIS investigation is led by Dr. Philip Christensen at Arizona State University. Lockheed Martin Astronautics, Denver, is the prime contractor for the Odyssey project, and developed and built the orbiter. Mission operations are conducted jointly from Lockheed Martin and from JPL, a division of the California Institute of Technology in Pasadena.

  12. More False Friends. Tuckische Fallen des deutsch-englishen Wortschatzes.

    ERIC Educational Resources Information Center

    Breitkreuz, Hartmut

    The second guide to "false friends," or false cognates, in German and English lists and discusses more difficult terms than the first guide. An introductory section defines false friends and discusses different types, and provides a set of symbols for distinguishing them. The first major section lists, alphabetically in German, and contains notes…

  13. Chinese Preschoolers' Implicit and Explicit False-Belief Understanding

    ERIC Educational Resources Information Center

    Wang, Bo; Low, Jason; Jing, Zhang; Qinghua, Qu

    2012-01-01

    Mandarin-speaking preschoolers in Mainland China (3- to 4-year-olds; N = 192) were tested for dissociations between anticipatory looking (AL) and verbal judgments on false-belief tasks. The dissociation between the two kinds of understanding was robust despite direct false-belief test questions using a Mandarin specific think-falsely verb and…

  14. 20 CFR 702.217 - Penalty for false statement, misrepresentation.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ...2011-04-01 2011-04-01 false Penalty for false statement, misrepresentation...Claims Procedures Notice § 702.217 Penalty for false statement, misrepresentation...S.C. 909, if the injury results in death, shall be punished by a fine not...

  15. 20 CFR 702.217 - Penalty for false statement, misrepresentation.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ...2013-04-01 2013-04-01 false Penalty for false statement, misrepresentation...Claims Procedures Notice § 702.217 Penalty for false statement, misrepresentation...S.C. 909, if the injury results in death, shall be punished by a fine not...

  16. 20 CFR 702.217 - Penalty for false statement, misrepresentation.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ...2012-04-01 2012-04-01 false Penalty for false statement, misrepresentation...Claims Procedures Notice § 702.217 Penalty for false statement, misrepresentation...S.C. 909, if the injury results in death, shall be punished by a fine not...

  17. 20 CFR 702.217 - Penalty for false statement, misrepresentation.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ...2010-04-01 2010-04-01 false Penalty for false statement, misrepresentation...Claims Procedures Notice § 702.217 Penalty for false statement, misrepresentation...S.C. 909, if the injury results in death, shall be punished by a fine not...

  18. 20 CFR 702.217 - Penalty for false statement, misrepresentation.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ...2014-04-01 2014-04-01 false Penalty for false statement, misrepresentation...Claims Procedures Notice § 702.217 Penalty for false statement, misrepresentation...S.C. 909, if the injury results in death, shall be punished by a fine not...

  19. Computing the apparent centroid of radar targets

    SciTech Connect

    Lee, C.E.

    1996-12-31

    A high-frequency multibounce radar scattering code was used as a simulation platform for demonstrating an algorithm to compute the ARC of specific radar targets. To illustrate this simulation process, several targets models were used. Simulation results for a sphere model were used to determine the errors of approximation associated with the simulation; verifying the process. The severity of glint induced tracking errors was also illustrated using a model of an F-15 aircraft. It was shown, in a deterministic manner, that the ARC of a target can fall well outside its physical extent. Finally, the apparent radar centroid simulation based on a ray casting procedure is well suited for use on most massively parallel computing platforms and could lead to the development of a near real-time radar tracking simulation for applications such as endgame fuzing, survivability, and vulnerability analyses using specific radar targets and fuze algorithms.

  20. Rapid-antigen detection tests for group a streptococcal pharyngitis: revisiting false-positive results using polymerase chain reaction testing.

    PubMed

    Cohen, Jérémie F; Cohen, Robert; Bidet, Philippe; Levy, Corinne; Deberdt, Patrice; d'Humières, Camille; Liguori, Sandrine; Corrard, François; Thollot, Franck; Mariani-Kurkdjian, Patricia; Chalumeau, Martin; Bingen, Edouard

    2013-06-01

    We investigated mechanisms of the false-positive test results on rapid-antigen detection test (RADT) for group A Streptococcal (GAS) pharyngitis. Most RADT false-positives (76%) were associated with polymerase chain reaction-positive GAS results, suggesting that RADT specificity could be considered close to 100%. Finding that 61% of GAS culture-negative but RADT-positive cases were positive on both GAS polymerase chain reaction and Staphylococcus aureus testing, we posit bacterial inhibition as causative. PMID:23465407

  1. [False positive death certification. Does the Lazarus phenomenon partly explain false positive death certification by rescue services in Germany, Austria and Switzerland?].

    PubMed

    Herff, H; Loosen, S-J; Paal, P; Mitterlechner, T; Rabl, W; Wenzel, V

    2010-04-01

    Apart from misdiagnosis, the Lazarus phenomenon, a spontaneous return of circulation after cardiac arrest, is a potential cause for false positive death certification. Because of medicolegal consequences and thus a negative publication bias, the incidence of false positive death certification is unknown. As a false positive death certification results in criminal prosecution and thus media interest, numerous media archives in Germany, Austria and Switzerland were searched for such reports. A total of nine cases of false positive death certification in these three countries were identified since the early 1990s of which eight occurred in an emergency medical service system setting. Apart from a lack of diligence of emergency physicians, a Lazarus phenomenon could be the reason for such incidents. As definite signs of death will not have developed only a few minutes after stopping CPR it might be difficult for an emergency physician to definitely certify a patient's death in an out-of-hospital setting with 100% safety. Thus, prehospital death certification poses a risk of error and subsequent legal prosecution of the emergency physician, as a Lazarus phenomenon may still occur in this phase. Delegation of death certification from emergency physicians to qualified physicians in a follow-up examination might increase both legal safety for emergency physicians in the field and patient safety. PMID:20224947

  2. Gusev Rocks Solidified from Lava (False Color)

    NASA Technical Reports Server (NTRS)

    2006-01-01

    In recent weeks, as NASA's Mars Exploration Rover Spirit has driven through the basin south of 'Husband Hill,' it has been traversing mainly sand and dune deposits. This week, though, Spirit has been maneuvering along the edge of an arc-shaped feature called 'Lorre Ridge' and has encountered some spectacular examples of basaltic rocks with striking textures. This panoramic camera (Pancam) image shows a group of boulders informally named 'FuYi.' These basaltic rocks were formed by volcanic processes and may be a primary constituent of Lorre Ridge and other interesting landforms in the basin.

    Spirit first encountered basalts at its landing site two years ago, on a vast plain covered with solidified lava that appeared to have flowed across Gusev Crater. Later, basaltic rocks became rare as Spirit climbed Husband Hill. The basaltic rocks that Spirit is now seeing are interesting because they exhibit many small holes or vesicles, similar to some kinds of volcanic rocks on Earth. Vesicular rocks form when gas bubbles are trapped in lava flows and the rock solidifies around the bubbles. When the gas escapes, it leaves holes in the rock. The quantity of gas bubbles in rocks on Husband Hill varies considerably; some rocks have none and some, such as several here at FuYi, are downright frothy.

    The change in textures and the location of the basalts may be signs that Spirit is driving along the edge of a lava flow. This lava may be the same as the basalt blanketing the plains of Spirit's landing site, or it may be different. The large size and frothy nature of the boulders around Lorre Ridge might indicate that eruptions once took place at the edge of the lava flow, where the lava interacted with the rocks of the basin floor. Scientists hope to learn more as Spirit continues to investigate these rocks.

    As Earth approaches the Chinese New Year (The Year of the Dog), the Athena science team decided to use nicknames representing Chinese culture and geography to identify rocks and features investigated by Spirit during the Chinese New Year celebration period. In ancient Chinese myth, FuYi was the first great emperor and lived in the east. He explained the theory of 'Yin' and 'Yang' to his people, invented the net to catch fish, was the first to use fire to cook food, and invented a musical instrument known as the 'Se' to accompany his peoples' songs and dances. Other rocks and features are being informally named for Chinese gods, warriors, inventors, and scientists, as well as rivers, lakes, and mountains.

    Spirit took this image on the rover's Martian day, or sol, 731 (Jan. 23, 2006). This is a false-color composite combining images taken with the Pancam's 750-nanometer, 530-nanometer and 430-nanometer filters.

  3. Do Optimal Prognostic Thresholds in Continuous Physiological Variables Really Exist? Analysis of Origin of Apparent Thresholds, with Systematic Review for Peak Oxygen Consumption, Ejection Fraction and BNP

    PubMed Central

    Leong, Tora; Rehman, Michaela B.; Pastormerlo, Luigi Emilio; Harrell, Frank E.; Coats, Andrew J. S.; Francis, Darrel P.

    2014-01-01

    Background Clinicians are sometimes advised to make decisions using thresholds in measured variables, derived from prognostic studies. Objectives We studied why there are conflicting apparently-optimal prognostic thresholds, for example in exercise peak oxygen uptake (pVO2), ejection fraction (EF), and Brain Natriuretic Peptide (BNP) in heart failure (HF). Data Sources and Eligibility Criteria Studies testing pVO2, EF or BNP prognostic thresholds in heart failure, published between 1990 and 2010, listed on Pubmed. Methods First, we examined studies testing pVO2, EF or BNP prognostic thresholds. Second, we created repeated simulations of 1500 patients to identify whether an apparently-optimal prognostic threshold indicates step change in risk. Results 33 studies (8946 patients) tested a pVO2 threshold. 18 found it prognostically significant: the actual reported threshold ranged widely (10–18 ml/kg/min) but was overwhelmingly controlled by the individual study population's mean pVO2 (r?=?0.86, p<0.00001). In contrast, the 15 negative publications were testing thresholds 199% further from their means (p?=?0.0001). Likewise, of 35 EF studies (10220 patients), the thresholds in the 22 positive reports were strongly determined by study means (r?=?0.90, p<0.0001). Similarly, in the 19 positives of 20 BNP studies (9725 patients): r?=?0.86 (p<0.0001). Second, survival simulations always discovered a “most significant” threshold, even when there was definitely no step change in mortality. With linear increase in risk, the apparently-optimal threshold was always near the sample mean (r?=?0.99, p<0.001). Limitations This study cannot report the best threshold for any of these variables; instead it explains how common clinical research procedures routinely produce false thresholds. Key Findings First, shifting (and/or disappearance) of an apparently-optimal prognostic threshold is strongly determined by studies' average pVO2, EF or BNP. Second, apparently-optimal thresholds always appear, even with no step in prognosis. Conclusions Emphatic therapeutic guidance based on thresholds from observational studies may be ill-founded. We should not assume that optimal thresholds, or any thresholds, exist. PMID:24475020

  4. 12 CFR Appendix B to Part 222 - Model Notices of Furnishing Negative Information

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ...2010-01-01 2010-01-01 false Model Notices of Furnishing Negative Information...222, App. B Appendix B to Part 222—Model Notices of Furnishing Negative Information a. Although use of the model notices is not required, a...

  5. Cortical Dynamics Subserving Visual Apparent Motion

    PubMed Central

    Hanazawa, Akitoshi; Undeman, Calle; Eriksson, David; Valentiniene, Sonata; Roland, Per E.

    2008-01-01

    Motion can be perceived when static images are successively presented with a spatial shift. This type of motion is an illusion and is termed apparent motion (AM). Here we show, with a voltage sensitive dye applied to the visual cortex of the ferret, that presentation of a sequence of stationary, short duration, stimuli which are perceived to produce AM are, initially, mapped in areas 17 and 18 as separate stationary representations. But time locked to the offset of the 1st stimulus, a sequence of signals are elicited. First, an activation traverses cortical areas 19 and 21 in the direction of AM. Simultaneously, a motion dependent feedback signal from these areas activates neurons between areas 19/21 and areas 17/18. Finally, an activation is recorded, traveling always from the representation of the 1st to the representation of the next or succeeding stimuli. This activation elicits spikes from neurons situated between these stimulus representations in areas 17/18. This sequence forms a physiological mechanism of motion computation which could bind populations of neurons in the visual areas to interpret motion out of stationary stimuli. PMID:18375528

  6. Apparent Benzene Solubility in Tetraphenylborate Slurries

    SciTech Connect

    Swingle, R.F.; Peterson, R.A.; Crawford, C.L.

    1997-11-01

    Personnel conducted testing to determine the apparent solubility of benzene in potassium tetraphenylborate (KTPB) slurries. The lack of benzene vapor pressure suppression in these tests indicate that for a 6.5 wt percent solids KTPB slurry in 4.65 M Na+ salt solution at approximately 25 degrees Celsius, no significant difference exists between the solubility of benzene in the slurry and the solubility of benzene in salt solution without KTPB solids. The work showed similar results in slurry with 6,000 mg/L sludge and 2,000 mg/L monosodium titanate added. Slurries containing tetraphenylborate decomposition intermediates (i.e., 4,200 mg/L triphenylboron (3PB), 510 mg/L diphenylborinic acid (2PB) and 1,500 mg/L phenylboric acid (1PB) or 100 mg/L tri-n-butylphosphate (TBP)) also showed no significant difference in benzene solubility form filtrate containing no KTPB solids. Slurry containing 2,000 mg/L Surfynol 420 did exhibit significant additional benzene solubility, as did irradiated slurries. The vapor pressure depression in the irradiated slurries presumably results from dissolution of biphenyl and other tetraphenylborate irradiation products in the benzene.

  7. Heterogeneity of apparently complete poliovirus particles.

    PubMed

    Tumilowicz, J J; Hummeler, K

    1964-05-01

    Tumilowicz, Joseph J. (Children's Hospital of Philadelphia, Philadelphia, Pa.), and Klaus Hummeler. Heterogeneity of apparently complete poliovirus particles. J. Bacteriol. 87:1105-1113. 1964.-A chromatographic procedure was developed for separating the N from the H complement-fixing antigen of poliovirus. This procedure concomitantly effected some separation of classes of N particle. The ratio of physical virus particles (PVP) to plaque-forming units (PFU) in N-reactive fractions varied from 6 to 51. Fractions with the lowest PVP-PFU ratios represented a considerable enrichment of PFU, when compared with the original ratio in each experiment. A direct relationship was found between the ratio of complement-fixing units of N antigen [CFU(N)] to 10(10) PVP and the ratio of PFU to 10(10) PVP for most of the N-reactive fractions. Large differences among the PVP-CFU(N) ratios, along with relatively constant PFU-CFU(N) ratios for most of the N fractions, indicated that N antigen is not distributed equally among non-H particles. Two possibilities, both compatible with the results, were discussed for the manner in which N antigen might be distributed. An absolute value of 10(7) PVP-CFU(N) was proposed for particles with a PVP-PFU ratio of 1. PMID:4289441

  8. Apparent discordant redshift QSO-galaxy associations

    NASA Astrophysics Data System (ADS)

    Lopez-Corredoira, Martin

    2010-11-01

    An "exotic" idea proposed by Viktor Ambartsumian was that new galaxies are formed through the ejection from older active galaxies. Galaxies beget galaxies, instead of the standard scenario in which galaxies stem from the evolution of the seeds derived from fluctuations in the initial density field. This idea is in some way contained in the speculative proposal that some or all QSOs might be objects ejected by nearby galaxies, and that their redshift is not cosmological(Arp, G./M. Burbidge and others). I will discuss some of the arguments for and against this scenario; in particular, I shall talk about the existence of real physical connections in apparently discordant QSO-galaxy redshift associations. On the one hand, there are many statistical correlations of high-redshift QSOs and nearby galaxies that cannot yet be explained in terms of gravitational lensing, biases, or selection effects; and some particular configurations have very low probabilities of being a projection of background objects. Our understanding of QSOs in general is also far from complete. On the other hand, some cases which were claimed to be anomalous in the past have found an explanation in standard terms. As an example, I will show some cases of our own research into this type: statistics of ULXs around nearby galaxies, and the Flesch & Hardcastle candidate QSOs catalog analysis. My own conclusion is neutral.

  9. The cognitive dynamics of negated sentence verification.

    PubMed

    Dale, Rick; Duran, Nicholas D

    2011-07-01

    We explored the influence of negation on cognitive dynamics, measured using mouse-movement trajectories, to test the classic notion that negation acts as an operator on linguistic processing. In three experiments, participants verified the truth or falsity of simple statements, and we tracked the computer-mouse trajectories of their responses. Sentences expressing these facts sometimes contained a negation. Such negated statements could be true (e.g., "elephants are not small") or false (e.g., "elephants are not large"). In the first experiment, as predicted by the classic notion of negation, we found that negation caused more discreteness in the mouse trajectory of a response. The second experiment induced a simple context for these statements, yet negation still increased discreteness in trajectories. A third experiment enhanced the pragmatic context of sentences, and the discreteness was substantially diminished, with one primary measure no longer significantly showing increased discreteness at all. Traditional linguistic theories predict rapid shifts in cognitive dynamics occur due to the nature of negation: It is an operator that reverses the truth or falsity of an interpretation. We argue that these results support both propositional and contextual accounts of negation present in the literature, suggesting that contextual factors are crucial for determining the kind of cognitive dynamics displayed. We conclude by drawing broader lessons about theories of cognition from the case of negation. PMID:21463359

  10. Apparent energy of hydrated biomineral surface and apparent solubility constant: An investigation of hydrozincite

    NASA Astrophysics Data System (ADS)

    Medas, Daniela; De Giudici, Giovanni; Podda, Francesca; Meneghini, Carlo; Lattanzi, Pierfranco

    2014-09-01

    The apparent solubility (Ksapp) of hydrozincite [Zn5(CO3)2(OH)6] was measured in samples of different nature, including natural abiotic (“geologic”), synthetic (abiotic), and natural biominerals. A systematic variation is recorded from log Ksapp = 6.2 ± 0.1 in geologic sample, log Ksapp between 7.0 ± 0.2 and 7.5 ± 0.2 in synthetic analogues, and log Ksapp between 8.8 ± 0.2 and 9.1 ± 0.2 in biomineral samples. Samples were thoroughly characterized by using SEM, TEM, synchrotron radiation X-rays powder diffraction (SR-XRPD), and Zn K-edge X-rays absorption spectroscopy (EXAFS). Refining SR-XRPD data, it was found a significant increase (up to 10%) in the cell volume of synthetic and biologic hydrozincites with respect to geologic samples. EXAFS analysis indicates small, but significant differences in the interatomic distances between samples of different nature. Previous studies had shown that crystal size is in the nanometer range for all samples, but decreases going from geologic to synthetic to biomineral samples. Combining these data with structural data obtained in this study, the effects on solubility of particle size and of cell volume increase were calculated by classical thermodynamic equations. The surface energy of hydrated hydrozincite increases by at least one order of magnitude from geologic to biologic sample. The effect of cell volume variation on apparent solubility is deemed negligible, being of the same order of magnitude of the error in solubility measurements. Thus, the different solubility of investigated samples is most likely ascribed to crystal size and surface energy. The measured apparent solubility constants were used to build predominance diagrams; specifically for biominerals, only the use of apparent Ksapp derived in this study predicts fairly well the seasonal variation of hydrozincite biomineralization at Naracauli, Sardinia.

  11. Decay of False Vacuum via Fuzzy Monopole in String Theory

    E-print Network

    Kasai, Aya

    2015-01-01

    We investigate dielectric branes in false vacua in Type IIB string theory. The dielectric branes are supported against collapsing by lower energy vacua inside spherical or tube-like branes. We claim that such branes can be seeds for semi-classical (or quantum mechanical) decay of the false vacua, which makes the life-time of the false vacua shorter. Also, we discuss a topology change of a bubble corresponding to the fuzzy monopole triggered by dissolving fundamental strings.

  12. De novo and apparent de novo hepatitis B virus infection after liver transplantation

    Microsoft Academic Search

    Bruno Roche; Didier Samuel; Michele Gigou; Cyrille Feray; Veronique Virot; Laurent Schmets; Marie Françoise David; Jean Louis Arulnaden; Alain Bismuth; Michel Reynes; Henri Bismuth

    1997-01-01

    Background\\/Aims: The aim of this study was to clarify the aetiology of apparent de novo HBV infection after liver transplantation.Methods: Twenty out of 570 HBsAg negative patients (3.5%) became HBsAg positive after transplantation and were studied. Donor and recipient sera were retrospectively tested for HBsAg, anti-HBs, anti-HBc, and HBV DNA by PCR. Donor and recipient livers were tested for HBV

  13. Apparent Double Crossing-Over in a Short Genetic Interval in Drosophila melanogaster

    Microsoft Academic Search

    M. M. Green

    1960-01-01

    IN view of the reported occurrence of double crossing-over within a short genetic interval in Aspergillus1 and of the purported existence of negative interference in bacteriophage2, it is worth while to record the recovery in Drosophila melanogaster of apparent double cross-over types within a short genetic interval where interference is nominally expected to be complete. These double cross-overs were found

  14. Earth's Climate Sensitivity: Apparent Inconsistencies in Recent Assessments

    NASA Astrophysics Data System (ADS)

    Schwartz, Stephen E.; Charlson, Robert J.; Kahn, Ralph; Rodhe, Henning

    2014-12-01

    Earth's equilibrium climate sensitivity (ECS) and forcing of Earth's climate system over the industrial era have been re-examined in two new assessments: the Fifth Assessment Report (AR5) of the Intergovernmental Panel on Climate Change (IPCC), and a study by Otto et al. (2013). The ranges of these quantities given in these assessments and also in the Fourth (2007) IPCC Assessment are analyzed here within the framework of a planetary energy balance model, taking into account the observed increase in global mean surface temperature over the instrumental record together with best estimates of the rate of increase of planetary heat content. This analysis shows systematic differences among the several assessments and apparent inconsistencies within individual assessments. Importantly, the likely range of ECS to doubled CO2 given in AR5, 1.5-4.5 K/(3.7 W m-2) exceeds the range inferred from the assessed likely range of forcing, 1.2-2.9 K/(3.7 W m-2), where 3.7 W m-2 denotes the forcing for doubled CO2. Such differences underscore the need to identify their causes and reduce the underlying uncertainties. Explanations might involve underestimated negative aerosol forcing, overestimated total forcing, overestimated climate sensitivity, poorly constrained ocean heating, limitations of the energy balance model, or a combination of effects.

  15. False fire alarms have a negative impact on UW operations False (or nuisance) alarms are very disruptive to UW operations. The alarms

    E-print Network

    Wilcock, William

    partitions and dust barriers ­ Review bid documents and specifications to establish what types of temporary fire partition and dust barrier measures are necessary for the specific job site. Barriers should by taking the following measures prior to and during construction. A pre-construction meeting specifically

  16. Accumulation of p53 protein as an indicator for p53 gene mutation in breast cancer. Occurrence of false-positives and false-negatives.

    PubMed

    Lohmann, D; Ruhri, C; Schmitt, M; Graeff, H; Höfler, H

    1993-03-01

    Accumulation of p53 protein resulting in levels detectable by immunohistochemistry (IHC) has been proposed as an indicator of mutation of the p53 gene. We have investigated a panel of 23 fresh-frozen breast cancers by IHC (PAb 1801), Southern and Northern blot analysis, and direct sequencing of the mutation hot spot regions (exons 5-8) of the p53 gene. Three tumors (13%) showed an intense nuclear staining in the majority of malignant cells, but only one of these showed a mutation of the p53 gene (codon 237, Arg to His). Furthermore, a mutation (5-bp deletion) was identified in a tumor that showed no p53 immunoreactivity. Our results indicate that accumulation of p53 protein, as detectable by IHC, is not a reliable indicator for p53 gene mutation in human breast cancer. PMID:8287224

  17. New Constraints on the False Positive Rate for Short-Period Kepler Planet Candidates

    NASA Astrophysics Data System (ADS)

    Colón, Knicole D.; Morehead, Robert C.; Ford, Eric B.

    2015-01-01

    The Kepler space mission has discovered thousands of potential planets orbiting other stars, thereby setting the stage for in-depth studies of different populations of planets. We present new multi-wavelength transit photometry of small (Rp < 6 Earth radii), short-period (P < 6 days) Kepler planet candidates acquired with the Gran Telescopio Canarias. Multi-wavelength transit photometry allows us to search for wavelength-dependent transit depths and subsequently identify eclipsing binary false positives (which are especially prevalent at the shortest orbital periods). We combine these new observations of three candidates with previous results for five other candidates (Colón & Ford 2011 and Colón, Ford, & Morehead 2012) to provide new constraints on the false positive rate for small, close-in candidates. In our full sample, we identify four candidates as viable planets and four as eclipsing binary false positives. We therefore find a higher false positive rate for small, close-in candidates compared to the lower false positive rate of ~10% determined by other studies for the full sample of Kepler planet candidates (e.g. Fressin et al. 2013). We also discuss the dearth of known planets with periods less than ~2.5 days and radii between ~3 and 11 Earth radii (the so-called 'sub-Jovian desert'), since the majority of the candidates in our study are located in or around this 'desert.' The lack of planets with these orbital and physical properties is not expected to be due to observational bias, as short-period planets are generally easier to detect (especially if they are larger or more massive than Earth). We consider the implications of our results for the other ~20 Kepler planet candidates located in this desert. Characterizing these candidates will allow us to better understand the formation processes of this apparently rare class of planets.

  18. Effects of Non-Differential Exposure Misclassification on False Conclusions in Hypothesis-Generating Studies

    PubMed Central

    Burstyn, Igor; Yang, Yunwen; Schnatter, A. Robert

    2014-01-01

    Despite the theoretical success of obviating the need for hypothesis-generating studies, they live on in epidemiological practice. Cole asserted that “… there is boundless number of hypotheses that could be generated, nearly all of them wrong” and urged us to focus on evaluating “credibility of hypothesis”. Adopting a Bayesian approach, we put this elegant logic into quantitative terms at the study planning stage for studies where the prior belief in the null hypothesis is high (i.e., “hypothesis-generating” studies). We consider not only type I and II errors (as is customary) but also the probabilities of false positive and negative results, taking into account typical imperfections in the data. We concentrate on a common source of imperfection in the data: non-differential misclassification of binary exposure classifier. In context of an unmatched case-control study, we demonstrate—both theoretically and via simulations—that although non-differential exposure misclassification is expected to attenuate real effect estimates, leading to the loss of ability to detect true effects, there is also a concurrent increase in false positives. Unfortunately, most investigators interpret their findings from such work as being biased towards the null rather than considering that they are no less likely to be false signals. The likelihood of false positives dwarfed the false negative rate under a wide range of studied settings. We suggest that instead of investing energy into understanding credibility of dubious hypotheses, applied disciplines such as epidemiology, should instead focus attention on understanding consequences of pursuing specific hypotheses, while accounting for the probability that the observed “statistically significant” association may be qualitatively spurious. PMID:25337942

  19. Effects of non-differential exposure misclassification on false conclusions in hypothesis-generating studies.

    PubMed

    Burstyn, Igor; Yang, Yunwen; Schnatter, A Robert

    2014-01-01

    Despite the theoretical success of obviating the need for hypothesis-generating studies, they live on in epidemiological practice. Cole asserted that "… there is boundless number of hypotheses that could be generated, nearly all of them wrong" and urged us to focus on evaluating "credibility of hypothesis". Adopting a Bayesian approach, we put this elegant logic into quantitative terms at the study planning stage for studies where the prior belief in the null hypothesis is high (i.e., "hypothesis-generating" studies). We consider not only type I and II errors (as is customary) but also the probabilities of false positive and negative results, taking into account typical imperfections in the data. We concentrate on a common source of imperfection in the data: non-differential misclassification of binary exposure classifier. In context of an unmatched case-control study, we demonstrate-both theoretically and via simulations-that although non-differential exposure misclassification is expected to attenuate real effect estimates, leading to the loss of ability to detect true effects, there is also a concurrent increase in false positives. Unfortunately, most investigators interpret their findings from such work as being biased towards the null rather than considering that they are no less likely to be false signals. The likelihood of false positives dwarfed the false negative rate under a wide range of studied settings. We suggest that instead of investing energy into understanding credibility of dubious hypotheses, applied disciplines such as epidemiology, should instead focus attention on understanding consequences of pursuing specific hypotheses, while accounting for the probability that the observed "statistically significant" association may be qualitatively spurious. PMID:25337942

  20. The number of negative modes of the oscillating bounces

    E-print Network

    George Lavrelashvili

    2006-02-10

    The spectrum of small perturbations about oscillating bounce solutions recently discussed in the literature is investigated. Our study supports quite intuitive and expected result: the bounce with N nodes has exactly N homogeneous negative modes. Existence of more than one negative modes makes obscure the relation of these oscillating bounce solutions to the false vacuum decay processes.

  1. False Allegations of Abuse and Neglect when Parents Separate

    ERIC Educational Resources Information Center

    Trocme, Nico; Bala, Nicholas

    2005-01-01

    Objective: The 1998 Canadian Incidence Study of Reported Child Abuse and Neglect (CIS-98) is the first national study to document the rate of intentionally false allegations of abuse and neglect investigated by child welfare services in Canada. This paper provides a detailed summary of the characteristics associated with intentionally false

  2. Creating false memories: Remembering words not presented in lists

    Microsoft Academic Search

    Henry L. Roediger; Kathleen B. McDermott

    1995-01-01

    Two experiments (modeled after J. Deese's 1959 study) revealed remarkable levels of false recall and false recognition in a list learning paradigm. In Experiment 1, subjects studied lists of 12 words (e.g., bed, rest, awake); each list was composed of associates of 1 nonpresented word (e.g., sleep). On immediate free recall tests, the nonpresented associates were recalled 40% of the

  3. The fSAM Model of False Recall

    ERIC Educational Resources Information Center

    Kimball, Daniel R.; Smith, Troy A.; Kahana, Michael J.

    2007-01-01

    The authors report a new theory of false memory building upon existing associative memory models and implemented in fSAM, the first fully specified quantitative model of false recall. Participants frequently intrude unstudied critical words while recalling lists comprising their strongest semantic associates but infrequently produce other…

  4. Effects of Aging and Education on False Memory

    ERIC Educational Resources Information Center

    Lee, Yuh-Shiow; Lee, Chia-Lin; Yang, Hua-Te

    2012-01-01

    This study examined the effects of aging and education on participants' false memory for words that were not presented. Three age groups of participants with either a high or low education level were asked to study lists of semantically related words. Both age and education were found to affect veridical and false memory, as indicated in the…

  5. Using Recall to Reduce False Recognition: Diagnostic and Disqualifying Monitoring

    ERIC Educational Resources Information Center

    Gallo, David A.

    2004-01-01

    Whether recall of studied words (e.g., parsley, rosemary, thyme) could reduce false recognition of related lures (e.g., basil) was investigated. Subjects studied words from several categories for a final recognition memory test. Half of the subjects were given standard test instructions, and half were instructed to use recall to reduce false

  6. Dekker's algorithm for two processes b 2 : boolean init false

    E-print Network

    Popeea, Corneliu - Chair for Foundations of Software Reliability and Theoretical Computer Science

    do begin h noncritical section i b i := true ; while b j do if k = j then begin b i := false ; while k = j do skip ; b i := true end ; hcritical sectioni; k := j; b i := false end ; #12; Dijkstra's algorithm for n processes var b;c: array [1 : : : n] of boolean init true var k; j: integer; while true do

  7. The false memory syndrome: Experimental studies and comparison to confabulations

    PubMed Central

    Mendez, M.F.; Fras, I.A.

    2011-01-01

    False memories, or recollections that are factually incorrect but strongly believed, remain a source of confusion for both psychiatrists and neurologists. We propose model for false memories based on recent experimental investigations, particularly when analyzed in comparison to confabulations, which are the equivalent of false memories from neurological disease. Studies using the Deese/Roedinger–McDermott experimental paradigm indicate that false memories are associated with the need for complete and integrated memories, self-relevancy, imagination and wish fulfillment, familiarity, emotional facilitation, suggestibility, and sexual content. In comparison, confabulations are associated with the same factors except for emotional facilitation, suggestibility, and sexual content. Both false memories and confabulations have an abnormal sense of certainty for their recollections, and neuroanatomical findings implicate decreased activity in the ventromedial frontal lobe in this certainty. In summary, recent studies of false memories in comparison to confabulations support a model of false memories as internally-generated but suggestible and emotionally-facilitated fantasies or impulses, rather than repressed memories of real events. Furthermore, like confabulations, in order for false memories to occur there must be an attenuation of the normal, nonconscious, right frontal “doubt tag” regarding their certainty. PMID:21177042

  8. Queue selection and switching by false clown anemonefish, Amphiprion ocellaris

    Microsoft Academic Search

    JEREMY MITCHELL

    2005-01-01

    Social groups of false clown anemonefish have been described as queues because, following settlement, fish acquire social rank passively by outliving more dominant groupmates. Within each queue, reproduction is restricted to the dominant pair. Therefore, individuals should adopt tactics that maximize their likelihood of attaining social dominance. Field observations indicated that, independent of an anemone's size, postlarval false clowns are

  9. False Belief Understanding in Cantonese-Speaking Children

    ERIC Educational Resources Information Center

    Tardif, Twila; Wellman, Henry M.; Cheung, Kar Man

    2004-01-01

    The present study investigates the performance of 96 Cantonese-speaking three- to five-year-old preschoolers on three false belief tasks--a deceptive object, a change of location, and an unexpected contents task encompassing a variety of task factors. Most importantly, the research examines the possibility that false belief performance depends on…

  10. Gain-Scheduled Fault Tolerance Control Under False Identification

    NASA Technical Reports Server (NTRS)

    Shin, Jong-Yeob; Belcastro, Christine (Technical Monitor)

    2006-01-01

    An active fault tolerant control (FTC) law is generally sensitive to false identification since the control gain is reconfigured for fault occurrence. In the conventional FTC law design procedure, dynamic variations due to false identification are not considered. In this paper, an FTC synthesis method is developed in order to consider possible variations of closed-loop dynamics under false identification into the control design procedure. An active FTC synthesis problem is formulated into an LMI optimization problem to minimize the upper bound of the induced-L2 norm which can represent the worst-case performance degradation due to false identification. The developed synthesis method is applied for control of the longitudinal motions of FASER (Free-flying Airplane for Subscale Experimental Research). The designed FTC law of the airplane is simulated for pitch angle command tracking under a false identification case.

  11. Mixed directional false discovery rate control in multiple pairwise comparisons using weighted p-values.

    PubMed

    Zhao, Haibing; Peddada, Shyamal D; Cui, Xinping

    2015-01-01

    In many applications, researchers are interested in making q pairwise comparisons among k test groups on the basis of m outcome variables. Often, m is very large. For example, such situations arise in gene expression microarray studies involving several experimental groups. Researchers are often not only interested in identifying differentially expressed genes between a given pair of experimental groups, but are also interested in making directional inferences such as whether a gene is up- or downregulated in one treatment group relative to another. In such situations, in addition to the usual errors such as false positive (Type I error) and false negative (Type II error), one may commit directional error (Type III error). For example, in a dose response microarray study, a gene may be declared to be upregulated in the high dose group compared to the low dose group when it is not. In this paper, we introduce a mixed directional false discovery rate (mdFDR) controlling procedure using weighted p-values to select positives in different directions. The weights are defined as the inverse of two times the proportion of either positive or negative discoveries. The proposed procedure has been proved mathematically to control the mdFDR at level ? and to have a larger power (which is defined as the expected proportion of nontrue null hypotheses) than the GSP10 procedure proposed by Guo et al. (2010). Simulation studies and real data analysis are also conducted to show the outperformance of the proposed procedure than the GSP10 procedure. PMID:25410394

  12. False positives complicate ancient pathogen identifications using high-throughput shotgun sequencing

    PubMed Central

    2014-01-01

    Background Identification of historic pathogens is challenging since false positives and negatives are a serious risk. Environmental non-pathogenic contaminants are ubiquitous. Furthermore, public genetic databases contain limited information regarding these species. High-throughput sequencing may help reliably detect and identify historic pathogens. Results We shotgun-sequenced 8 16th-century Mixtec individuals from the site of Teposcolula Yucundaa (Oaxaca, Mexico) who are reported to have died from the huey cocoliztli (‘Great Pestilence’ in Nahautl), an unknown disease that decimated native Mexican populations during the Spanish colonial period, in order to identify the pathogen. Comparison of these sequences with those deriving from the surrounding soil and from 4 precontact individuals from the site found a wide variety of contaminant organisms that confounded analyses. Without the comparative sequence data from the precontact individuals and soil, false positives for Yersinia pestis and rickettsiosis could have been reported. Conclusions False positives and negatives remain problematic in ancient DNA analyses despite the application of high-throughput sequencing. Our results suggest that several studies claiming the discovery of ancient pathogens may need further verification. Additionally, true single molecule sequencing’s short read lengths, inability to sequence through DNA lesions, and limited ancient-DNA-specific technical development hinder its application to palaeopathology. PMID:24568097

  13. On the Causes of Frequency-Dependent Apparent Seismological Q

    NASA Astrophysics Data System (ADS)

    Morozov, Igor B.

    2010-10-01

    Variability of the Earth’s structure makes a first-order impact on attenuation measurements which often does not receive adequate attention. Geometrical spreading (GS) can be used as a simple measure of the effects of such structure. The traditional simplified GS compensation is insufficiently accurate for attenuation measurements, and the residual GS appears as biases in both Q 0 and ? parameters in the frequency-dependent attenuation law Q( f) = Q 0 f ? . A new interpretation approach bypassing Q( f) and using the attenuation coefficient ?( f) = ? + ?f/ Q e( f) resolves this problem by directly measuring the residual GS, denoted ?, and effective attenuation, Q e. The approach is illustrated by re-interpreting several published datasets, including nuclear-explosion and local-earthquake codas, Pn, and synthetic 50-300-s surface waves. Some of these examples were key to establishing the Q( f) concept. In all examples considered, ?( f) shows a linear dependence on the frequency, ? ? 0, and Q e can be considered frequency-independent. Short-period crustal body waves are characterized by positive ? SP values of (0.6-2.0) × 10-2 s-1 interpreted as related to the downward upper-crustal reflectivity. Long-period surface waves show negative ? LP ? -1.9 × 10-5 s-1, which could be caused by insufficient modeling accuracy at long periods. The above ? values also provide a simple explanation for the absorption band observed within the Earth. The band is interpreted as apparent and formed by levels of Q e ? 1,100 within the crust decreasing to Q e ? 120 within the uppermost mantle, with frequencies of its flanks corresponding to ? LP and ? SP. Therefore, the observed absorption band could be purely geometrical in nature, and relaxation or scattering models may not be necessary for explaining the observed apparent Q( f). Linearity of the attenuation coefficient suggests that at all periods, the attenuation of both Rayleigh and Love waves should be principally accumulated at the sub-crustal depths (~38-100 km).

  14. The Illusion of the Positive: The impact of natural and induced mood on older adults’ false recall

    PubMed Central

    Emery, Lisa; Hess, Thomas M.; Elliot, Tonya

    2012-01-01

    Recent research suggests that affective and motivational processes can influence age differences in memory. In the current study, we examine the impact of both natural and induced mood state on age differences in false recall. Older and younger adults performed a version of the Deese-Roediger-McDermott (DRM; Roediger & McDermott, 1995) false memory paradigm in either their natural mood state or after a positive or negative mood induction. Results indicated that, after accounting for age differences in basic cognitive function, age-related differences in positive mood during the testing session were related to increased false recall in older adults. Inducing older adults into a positive mood also exacerbated age differences in false memory. In contrast, veridical recall did not appear to be systematically influenced by mood. Together, these results suggest that positive mood states can impact older adults’ information processing and potentially increase underlying cognitive age differences. PMID:22292431

  15. Apparent Horizons in Vacuum Robinson-Trautman Spacetimes

    E-print Network

    E. W. M. Chow; A. W. -C. Lun

    1995-04-01

    Vacuum asymptotically flat Robinson-Trautman spacetimes are a well known class of spacetimes exhibiting outgoing gravitational radiation. In this paper we describe a method of locating the past apparent horizon in these spacetimes, and discuss the properties of the horizon. We show that the past apparent horizon is non-timelike, and that its surface area is a decreasing function of the retarded time. A numerical simulation of the apparent horizon is also discussed.

  16. Apparent-Strain Correction for Combined Thermal and Mechanical Testing

    NASA Technical Reports Server (NTRS)

    Johnson, Theodore F.; O'Neil, Teresa L.

    2007-01-01

    Combined thermal and mechanical testing requires that the total strain be corrected for the coefficient of thermal expansion mismatch between the strain gage and the specimen or apparent strain when the temperature varies while a mechanical load is being applied. Collecting data for an apparent strain test becomes problematic as the specimen size increases. If the test specimen cannot be placed in a variable temperature test chamber to generate apparent strain data with no mechanical loads, coupons can be used to generate the required data. The coupons, however, must have the same strain gage type, coefficient of thermal expansion, and constraints as the specimen to be useful. Obtaining apparent-strain data at temperatures lower than -320 F is challenging due to the difficulty to maintain steady-state and uniform temperatures on a given specimen. Equations to correct for apparent strain in a real-time fashion and data from apparent-strain tests for composite and metallic specimens over a temperature range from -450 F to +250 F are presented in this paper. Three approaches to extrapolate apparent-strain data from -320 F to -430 F are presented and compared to the measured apparent-strain data. The first two approaches use a subset of the apparent-strain curves between -320 F and 100 F to extrapolate to -430 F, while the third approach extrapolates the apparent-strain curve over the temperature range of -320 F to +250 F to -430 F. The first two approaches are superior to the third approach but the use of either of the first two approaches is contingent upon the degree of non-linearity of the apparent-strain curve.

  17. Age-related changes in False Recognition: An ERP Study 

    E-print Network

    Robb, Lindsey

    2011-01-01

    /new effect (~400 to 800ms) and adapting a paradigm used by Koutstaal (2006) which successfully demonstrated high false recognition in participants using picture stimuli. Participants undertook two explicit forced choice tasks: unintentionally studying picture...

  18. Cognitive neuroscience of false memory: the role of gist memory 

    E-print Network

    Bellamy, Katarina Jane

    2010-01-01

    This thesis explores the role of gist memory and gist representation in the formation of false recognition, specifically in the Deese, Roediger and McDermott Paradigm. We found that normal individuals displayed a range ...

  19. 7 CFR 28.961 - False and misleading information.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ...COMMODITY STANDARDS AND STANDARD CONTAINER REGULATIONS COTTON CLASSING, TESTING, AND STANDARDS Cotton Fiber and Processing Tests Fiber and Processing Tests § 28.961 False and misleading information. The publication or...

  20. Animals in Education: Are We Prisoners of False Sentiment?

    ERIC Educational Resources Information Center

    Minerney, Joseph D.

    1993-01-01

    Asserts that concerns over the use of animals in science education is confounded by the unworthy introduction of false sentiment by animal rights groups, which persist in ignoring the realities of biology. (PR)

  1. 7 CFR 28.961 - False and misleading information.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ...DEPARTMENT OF AGRICULTURE COMMODITY STANDARDS AND STANDARD CONTAINER REGULATIONS COTTON CLASSING, TESTING, AND STANDARDS Cotton Fiber and Processing Tests Fiber and Processing Tests § 28.961 False and misleading information....

  2. 7 CFR 28.961 - False and misleading information.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ...DEPARTMENT OF AGRICULTURE COMMODITY STANDARDS AND STANDARD CONTAINER REGULATIONS COTTON CLASSING, TESTING, AND STANDARDS Cotton Fiber and Processing Tests Fiber and Processing Tests § 28.961 False and misleading information....

  3. 7 CFR 28.961 - False and misleading information.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ...DEPARTMENT OF AGRICULTURE COMMODITY STANDARDS AND STANDARD CONTAINER REGULATIONS COTTON CLASSING, TESTING, AND STANDARDS Cotton Fiber and Processing Tests Fiber and Processing Tests § 28.961 False and misleading information....

  4. 7 CFR 28.961 - False and misleading information.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ...DEPARTMENT OF AGRICULTURE COMMODITY STANDARDS AND STANDARD CONTAINER REGULATIONS COTTON CLASSING, TESTING, AND STANDARDS Cotton Fiber and Processing Tests Fiber and Processing Tests § 28.961 False and misleading information....

  5. False-positive (111)In-pentetreotide Uptake in Gastritis.

    PubMed

    Usmani, Sharjeel; Alshammari, Alshaima

    2013-05-01

    (111)In-pentetreotide [(111)In-octreoscan] is the most widely used radiolabeled somatostatin analog for evaluating neuroendocrine tumor overexpression of somatostatin receptors. False-positives studies of somatostatin receptor scintigraphy have been reported and often the cause is unexplained but assumed to be due to high number of somatostatin receptors in other pathologies. Causes of false-positives include visualization of the gallbladder, nasal mucosa and pulmonary hilar areas in respiratory infections, thyroid abnormalities, accessory spleens, recent Cerebrovascular accidents (CVA's) and activity at the site of a recent surgical incision. In infection or inflammation the cause of false-positive uptake is probably the result of tracer binding by somatostatin receptors on the inflammatory leukocytes. In this case report, we report, a 44-year-old male patient with false-positive (111)In-pentetreotide uptake due to gastritis. PMID:25126002

  6. 50 CFR 216.94 - False statements or endorsements.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ...ADMINISTRATION, DEPARTMENT OF COMMERCE MARINE MAMMALS REGULATIONS GOVERNING THE TAKING AND IMPORTING OF MARINE MAMMALS Dolphin Safe Tuna Labeling § 216.94 False statements or endorsements. Any person who knowingly and willfully makes a...

  7. 50 CFR 216.94 - False statements or endorsements.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ...ADMINISTRATION, DEPARTMENT OF COMMERCE MARINE MAMMALS REGULATIONS GOVERNING THE TAKING AND IMPORTING OF MARINE MAMMALS Dolphin Safe Tuna Labeling § 216.94 False statements or endorsements. Any person who knowingly and willfully makes a...

  8. 50 CFR 216.94 - False statements or endorsements.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ...ADMINISTRATION, DEPARTMENT OF COMMERCE MARINE MAMMALS REGULATIONS GOVERNING THE TAKING AND IMPORTING OF MARINE MAMMALS Dolphin Safe Tuna Labeling § 216.94 False statements or endorsements. Any person who knowingly and willfully makes a...

  9. 50 CFR 216.94 - False statements or endorsements.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ...ADMINISTRATION, DEPARTMENT OF COMMERCE MARINE MAMMALS REGULATIONS GOVERNING THE TAKING AND IMPORTING OF MARINE MAMMALS Dolphin Safe Tuna Labeling § 216.94 False statements or endorsements. Any person who knowingly and willfully makes a...

  10. 50 CFR 216.94 - False statements or endorsements.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ...ADMINISTRATION, DEPARTMENT OF COMMERCE MARINE MAMMALS REGULATIONS GOVERNING THE TAKING AND IMPORTING OF MARINE MAMMALS Dolphin Safe Tuna Labeling § 216.94 False statements or endorsements. Any person who knowingly and willfully makes a...

  11. False alarm mitigation techniques for hyperspectral target detection

    NASA Astrophysics Data System (ADS)

    Pieper, M. L.; Manolakis, D.; Truslow, E.; Cooley, T.; Brueggeman, M.

    2013-05-01

    A challenging problem of major importance in hyperspectral imaging applications is the detection of subpixel objects of military and civilian interest. High false alarm thresholds are required to detect subpixel objects due to the large amount of surrounding background clutter. These high false alarm rates are unacceptable for military purposes, requiring the need for false alarm mitigation (FAM) techniques to weed out the objects of interest. The objective of this paper is to provide a comparison of the implementation of these FAM techniques and their inherent benefits in the whitened detection space. The widely utilized matched filter (MF) and adaptive cosine estimator (ACE) are both based on a linear mixing model (LMM) between a background and object class. The matched filter approximates the object abundance, and the ACE measures the model error. Each of these measurements provides inadequate object separation alone, but by using both the object abundance and model error, the objects can be separated from the false alarms.

  12. The effect of Twitter exposure on false memory formation.

    PubMed

    Fenn, Kimberly M; Griffin, Nicholas R; Uitvlugt, Mitchell G; Ravizza, Susan M

    2014-12-01

    Social media sites such as Facebook and Twitter have increased drastically in popularity. However, information on these sites is not verified and may contain inaccuracies. It is well-established that false information encountered after an event can lead to memory distortion. Therefore, social media may be particularly harmful for autobiographical memory. Here, we tested the effect of Twitter on false memory. We presented participants with a series of images that depicted a story and then presented false information about the images in a scrolling feed that bore either a low or high resemblance to a Twitter feed. Confidence for correct information was similar across the groups, but confidence for suggested information was significantly lower when false information was presented in a Twitter format. We propose that individuals take into account the medium of the message when integrating information into memory. PMID:24825304

  13. Endovascular repair of aortic arch false aneurysm with branched endograft.

    PubMed

    Schiro, Andrew; Kuhan, Ganesh; Pichel, Adam; Farquharson, Finn; Murray, David; Serracino-Inglott, Ferdinand

    2014-09-01

    This case report describes the use of a customized branched device for the treatment of a distal anastomotic false aneurysm in an ascending to descending interposition graft in a 34-year-old Jehovah's Witness with congenital aortic arch interruption. A single branched customized stent graft device was used to successfully exclude the false aneurysm. The procedure was challenging due to the abnormal congenital anatomy. The planning, operative technique, and successful execution are described in this case report. PMID:23958071

  14. Analysis of Postsurgical Aortic False Aneurysm in 27 Patients

    PubMed Central

    Malvindi, Pietro Giorgio; Cappai, Antioco; Raffa, Giuseppe Maria; Barbone, Alessandro; Basciu, Alessio; Citterio, Enrico; Ornaghi, Diego; Tarelli, Giuseppe; Settepani, Fabrizio

    2013-01-01

    Aortic false aneurysm is a rare complication after cardiac surgery. In recent years, improved results have been reported in regard to the surgical management of these high-risk lesions. We retrospectively examined 28 consecutive cases (in 27 patients) of postsurgical aortic false aneurysm diagnosed at our institution from May 1999 through December 2011. Twenty-four patients underwent reoperation. Cardiopulmonary bypass was instituted before sternotomy in 15 patients (63%). Isolated repair of the aortic false aneurysm was performed in 15 patients. Four patients (including one who had already undergone repeat false-aneurysm repair) declined surgery in favor of clinical monitoring. Eleven patients were asymptomatic at the time of diagnosis. In the other 16, the main cause was infection in 7, and previous operation for acute aortic dissection in 9. The in-hospital mortality rate was 16.6% (4 patients, 3 of whom had infective false aneurysms). Relevant postoperative sequelae were noted in 7 patients (29%). The cumulative 1-year and 5-year survival rates were 83% and 62%, respectively. The 4 patients who did not undergo reoperation were alive at a median interval of 23 months (range, 9–37 mo). Two underwent imaging evaluations; in one, computed tomography revealed an 8-mm increase of the false aneurysm's maximal diameter at 34 months. Aortic false aneurysm can develop silently. Surgical procedures should be proposed even to asymptomatic patients because of the unpredictable evolution of the condition. Radical aortic-graft replacement should be chosen rather than simple repair, because recurrent false aneurysm is possible. PMID:23914017

  15. Pixel-based image fusion with false color mapping

    Microsoft Academic Search

    Wei Zhao; Shiyi Mao

    2003-01-01

    In this paper, we propose a pixel-based image fusion algorithm that combines the gray-level image fusion method with the false color mapping. This algorithm integrates two gray-level images presenting different sensor modalities or at different frequencies and produces a fused false-color image. The resulting image has higher information content than each of the original images. The objects in the fused

  16. Clinical Significance of CK19 Negative Breast Cancer

    PubMed Central

    Fujisue, Mamiko; Nishimura, Reiki; Okumura, Yasuhiro; Tashima, Rumiko; Nishiyama, Yasuyuki; Osako, Tomofumi; Toyozumi, Yasuo; Arima, Nobuyuki

    2012-01-01

    Analysis of sentinel lymph nodes (SLNs) by means of One-Step Nucleic Acid Amplification (OSNA) is gaining widespread use as a quick and accurate method. This assay detects the expression level of cytokeratin 19 (CK19) which is present in some but not all breast tumors. In this study, the clinical significance of negative CK19 was investigated in 219 cases of primary breast cancer. In 179 patients with clinically negative nodes, OSNA and imprint smear cytology of SLN were performed simultaneously. The OSNA revealed a node-positive rate of 24.6%. Negative CK19 correlated significantly with negative ER/PgR and higher Ki-67 values, and marginally with higher nuclear grade and p53 overexpression. The triple negative subtype showed lower CK19 expression. OSNA revealed that one of the negative CK19 cases was actually a false negative but this was corrected with the use of the imprint smear cytology. In conclusion, CK19 negativity reflected the aggressiveness of primary breast cancer. OSNA assay used to analyze SLN was useful, but there is a possibility that it will mistakenly detect false negatives in CK19 negative tumors. Therefore, in tumors with negative CK19, the imprint smear cytology may be more useful in cases with macrometastasis. PMID:24216695

  17. False-positive ethanol blood concentrations leading to clinical confusion on Christmas Day.

    PubMed

    Jones, Terry E

    2011-11-01

    A case of altered consciousness in which ethanol ingestion was one of the differential diagnoses is described. Three separate blood samples were conveyed to the hospital biochemistry laboratory and each returned a positive value when assayed via an indirect, enzymatic method. The family strongly denied alcohol ingestion and hence, a few days later, the samples were conveyed to an external laboratory using a 'specific', chromatographic method. These samples were all reported as negative for ethanol. Alternative causes of altered consciousness were restricted by the false-positive ethanol laboratory results. PMID:21854765

  18. Negative-ion states

    SciTech Connect

    Compton, R.N.

    1982-01-01

    In this brief review, we discuss some of the properties of atomic and molecular negative ions and their excited states. Experiments involving photon reactions with negative ions and polar dissociation are summarized. 116 references, 14 figures.

  19. False-alarm characterization in hyperspectral gas-detection applications

    NASA Astrophysics Data System (ADS)

    DiPietro, Robert S.; Truslow, Eric; Manolakis, Dimitris G.; Golowich, Steven E.; Lockwood, Ronald B.

    2012-09-01

    Chemical cloud detection using long-wave infrared (LWIR) hyperspectral-imaging sensors has many civilian and military applications, including chemical warfare threat mitigation, environmental monitoring, and emergency response. Current capabilities are limited by variation in background clutter as opposed to the physics of photon detection, and this makes the statistical characterization of clutter and clutter-induced false alarms essential to the design of practical systems. In this exploratory work, we use hyperspectral data collected both on the ground and in the air to spectrally and spatially characterize false alarms. Focusing on two widely-used detectors, the matched filter (MF) and the adaptive cosine estimator (ACE), we compare empirical false-alarm rates to their theoretical counterparts - detector output under Gaussian, t and t-mixture distributed data - and show that these models often underestimate false-alarm rates. Next, we threshold real detection maps and show that true detections and false alarms often exhibit very different spatial behavior. To exploit this difference and understand how spatial processing affects performance, the spatial behavior of false alarms must be understood. We take a first step in this direction by showing that, although the behavior may `look' quite random, it is not well captured by the complete-spatial-randomness model. Finally, we describe how our findings impact the design of real detection systems.

  20. Surface shape from the deformation of apparent contours

    Microsoft Academic Search

    Roberto Cipolla; Andrew Blake

    1992-01-01

    The spatiotemporal analysis of deforming silhouettes (apparent contours) is here extended using the mathematics of perspective projections and tools from differential geometry. Analysis of the image motion of a silhouette or apparent contour enables computation of local surface curvature along the corresponding contour generator on the surface, assuming viewer motion is known. To perform the analysis, a spatiotemporal parameterization of

  1. Magnetoencephalographic study of speed-dependent responses in apparent motion

    Microsoft Academic Search

    Hovagim Bakardjian; Akira Uchida; Hiroshi Endo; Tsunehiro Takeda

    2002-01-01

    Objectives: There have been only few studies of visually-evoked cortical responses to apparent motion as a function of stimulus speed. Most earlier findings on evoked peak magnitudes and latencies, utilizing various types of smooth and apparent motion stimuli, have demonstrated that greater spatial separation\\/speed resulted in enhanced peak magnitudes, decreasing onset latencies in individual extrastriate neurons and in shorter motor

  2. Sentential Negation in English

    ERIC Educational Resources Information Center

    Mowarin, Macaulay

    2009-01-01

    This paper undertakes a detailed analysis of sentential negation in the English language with Chomsky's Government-Binding theory of Transformational Grammar as theoretical model. It distinguishes between constituent and sentential negation in English. The essay identifies the exact position of Negation phrase in an English clause structure. It…

  3. Multiple weather factors affect apparent survival of European passerine birds.

    PubMed

    Salewski, Volker; Hochachka, Wesley M; Fiedler, Wolfgang

    2013-01-01

    Weather affects the demography of animals and thus climate change will cause local changes in demographic rates. In birds numerous studies have correlated demographic factors with weather but few of those examined variation in the impacts of weather in different seasons and, in the case of migrants, in different regions. Using capture-recapture models we correlated weather with apparent survival of seven passerine bird species with different migration strategies to assess the importance of selected facets of weather throughout the year on apparent survival. Contrary to our expectations weather experienced during the breeding season did not affect apparent survival of the target species. However, measures for winter severity were associated with apparent survival of a resident species, two short-distance/partial migrants and a long-distance migrant. Apparent survival of two short distance migrants as well as two long-distance migrants was further correlated with conditions experienced during the non-breeding season in Spain. Conditions in Africa had statistically significant but relatively minor effects on the apparent survival of the two long-distance migrants but also of a presumably short-distance migrant and a short-distance/partial migrant. In general several weather effects independently explained similar amounts of variation in apparent survival for the majority of species and single factors explained only relatively low amounts of temporal variation of apparent survival. Although the directions of the effects on apparent survival mostly met our expectations and there are clear predictions for effects of future climate we caution against simple extrapolations of present conditions to predict future population dynamics. Not only did weather explains limited amounts of variation in apparent survival, but future demographics will likely be affected by changing interspecific interactions, opposing effects of weather in different seasons, and the potential for phenotypic and microevolutionary adaptations. PMID:23593131

  4. A Theory of False Cognitive Expectancies in Airline Pilots

    NASA Astrophysics Data System (ADS)

    Cortes, Antonio I.

    The Theory of False Cognitive Expectancies was developed by studying high reliability flight operations. Airline pilots depend extensively on cognitive expectancies to perceive, understand, and predict actions and events. Out of 1,363 incident reports submitted by airline pilots to the National Aeronautics and Space Administration Aviation Safety Reporting System over a year's time, 110 reports were found to contain evidence of 127 false cognitive expectancies in pilots. A comprehensive taxonomy was developed with six categories of interest. The dataset of 127 false expectancies was used to initially code tentative taxon values for each category. Intermediate coding through constant comparative analysis completed the taxonomy. The taxonomy was used for the advanced coding of chronological context-dependent visualizations of expectancy factors, known as strands, which depict the major factors in the creation and propagation of each expectancy. Strands were mapped into common networks to detect highly represented expectancy processes. Theoretical integration established 11 sources of false expectancies, the most common expectancy errors, and those conspicuous factors worthy of future study. The most prevalent source of false cognitive expectancies within the dataset was determined to be unconscious individual modeling based on past events. Integrative analyses also revealed relationships between expectancies and flight deck automation, unresolved discrepancies, and levels of situation awareness. Particularly noteworthy were the findings that false expectancies can combine in three possible permutations to diminish situation awareness and examples of how false expectancies can be unwittingly transmitted from one person to another. The theory resulting from this research can enhance the error coding process used during aircraft line oriented safety audits, lays the foundation for developing expectancy management training programs, and will allow researchers to proffer hypotheses for human testing using flight simulators.

  5. A FALSE POSITIVE FOR OCEAN GLINT ON EXOPLANETS: THE LATITUDE-ALBEDO EFFECT

    SciTech Connect

    Cowan, Nicolas B. [Center for Interdisciplinary Exploration and Research in Astrophysics and Department of Physics and Astronomy, Northwestern University, 2131 Tech Drive, Evanston, IL 60208 (United States); Abbot, Dorian S. [Department of Geophysical Sciences, University of Chicago, 5734 South Ellis Avenue, Chicago, IL 60637 (United States); Voigt, Aiko [Max Planck Institute for Meteorology, Bundesstr. 53, D-20146, Hamburg (Germany)

    2012-06-10

    Identifying liquid water on the surface of planets is a high priority, as this traditionally defines habitability. One proposed signature of oceans is specular reflection ('glint'), which increases the apparent albedo of a planet at crescent phases. We post-process a global climate model of an Earth-like planet to simulate reflected light curves. Significantly, we obtain glint-like phase variations even though we do not include specular reflection in our model. This false positive is the product of two generic properties: (1) for modest obliquities, a planet's poles receive less orbit-averaged stellar flux than its equator, so the poles are more likely to be covered in highly reflective snow and ice; and (2) we show that reflected light from a modest-obliquity planet at crescent phases probes higher latitudes than at gibbous phases, therefore a planet's apparent albedo will naturally increase at crescent phase. We suggest that this 'latitude-albedo effect' will operate even for large obliquities: in that case the equator receives less orbit-averaged flux than the poles, and the equator is preferentially sampled at crescent phase. Using rotational and orbital color variations to map the surfaces of directly imaged planets and estimate their obliquity will therefore be a necessary pre-condition for properly interpreting their reflected phase variations. The latitude-albedo effect is a particularly convincing glint false positive for zero-obliquity planets, and such worlds are not amenable to latitudinal mapping. This effect severely limits the utility of specular reflection for detecting oceans on exoplanets.

  6. Implicit false-belief processing in the human brain.

    PubMed

    Schneider, Dana; Slaughter, Virginia P; Becker, Stefanie I; Dux, Paul E

    2014-11-01

    Eye-movement patterns in 'Sally-Anne' tasks reflect humans' ability to implicitly process the mental states of others, particularly false-beliefs - a key theory of mind (ToM) operation. It has recently been proposed that an efficient ToM system, which operates in the absence of awareness (implicit ToM, iToM), subserves the analysis of belief-like states. This contrasts to consciously available belief processing, performed by the explicit ToM system (eToM). The frontal, temporal and parietal cortices are engaged when humans explicitly 'mentalize' about others' beliefs. However, the neural underpinnings of implicit false-belief processing and the extent to which they draw on networks involved in explicit general-belief processing are unknown. Here, participants watched 'Sally-Anne' movies while fMRI and eye-tracking measures were acquired simultaneously. Participants displayed eye-movements consistent with implicit false-belief processing. After independently localizing the brain areas involved in explicit general-belief processing, only the left anterior superior temporal sulcus and precuneus revealed greater blood-oxygen-level-dependent activity for false- relative to true-belief trials in our iToM paradigm. No such difference was found for the right temporal-parietal junction despite significant activity in this area. These findings fractionate brain regions that are associated with explicit general ToM reasoning and false-belief processing in the absence of awareness. PMID:25042446

  7. Deficient cognitive control fuels children's exuberant false allegations.

    PubMed

    Poole, Debra Ann; Dickinson, Jason J; Brubacher, Sonja P; Liberty, Allison E; Kaake, Amanda M

    2014-02-01

    In eyewitness studies as in actual investigations, a minority of children generate numerous false (and sometimes incredulous) allegations. To explore the characteristics of these children, we reinterviewed and administered a battery of tasks to 61 children (ages 4-9 years) who had previously participated in an eyewitness study where a man broke a "germ rule" twice when he tried to touch them. Performance on utilization, response conflict (Luria tapping), and theory of mind tasks predicted the number of false reports of touching (with age and time since the event controlled) and correctly classified 90.16% of the children as typical witnesses or exuberant (more than 3) false reporters. Results of a factor analysis pointed to a common process underlying performance on these tasks that accounted for 49% of the variability in false reports. Relations between task performance and testimony confirmed that the mechanisms underlying occasional intrusions are different from those that drive persistent confabulation and that deficient cognitive control fuels young children's exuberant false reports. PMID:24157217

  8. The Effect of Visual Apparent Motion on Audiovisual Simultaneity

    PubMed Central

    Kwon, Jinhwan; Ogawa, Ken-ichiro; Miyake, Yoshihiro

    2014-01-01

    Visual motion information from dynamic environments is important in multisensory temporal perception. However, it is unclear how visual motion information influences the integration of multisensory temporal perceptions. We investigated whether visual apparent motion affects audiovisual temporal perception. Visual apparent motion is a phenomenon in which two flashes presented in sequence in different positions are perceived as continuous motion. Across three experiments, participants performed temporal order judgment (TOJ) tasks. Experiment 1 was a TOJ task conducted in order to assess audiovisual simultaneity during perception of apparent motion. The results showed that the point of subjective simultaneity (PSS) was shifted toward a sound-lead stimulus, and the just noticeable difference (JND) was reduced compared with a normal TOJ task with a single flash. This indicates that visual apparent motion affects audiovisual simultaneity and improves temporal discrimination in audiovisual processing. Experiment 2 was a TOJ task conducted in order to remove the influence of the amount of flash stimulation from Experiment 1. The PSS and JND during perception of apparent motion were almost identical to those in Experiment 1, but differed from those for successive perception when long temporal intervals were included between two flashes without motion. This showed that the result obtained under the apparent motion condition was unaffected by the amount of flash stimulation. Because apparent motion was produced by a constant interval between two flashes, the results may be accounted for by specific prediction. In Experiment 3, we eliminated the influence of prediction by randomizing the intervals between the two flashes. However, the PSS and JND did not differ from those in Experiment 1. It became clear that the results obtained for the perception of visual apparent motion were not attributable to prediction. Our findings suggest that visual apparent motion changes temporal simultaneity perception and improves temporal discrimination in audiovisual processing. PMID:25295594

  9. False memory in aging: effects of emotional valence on word recognition accuracy.

    PubMed

    Piguet, Olivier; Connally, Emily; Krendl, Anne C; Huot, Jessica R; Corkin, Suzanne

    2008-06-01

    Memory is susceptible to distortions. Valence and increasing age are variables known to affect memory accuracy and may increase false alarm production. Interaction between these variables and their impact on false memory was investigated in 36 young (18-28 years) and 36 older (61-83 years) healthy adults. At study, participants viewed lists of neutral words orthographically related to negative, neutral, or positive critical lures (not presented). Memory for these words was subsequently tested with a remember-know procedure. At test, items included the words seen at study and their associated critical lures, as well as sets of orthographically related neutral words not seen at study and their associated unstudied lures. Positive valence was shown to have two opposite effects on older adults' discrimination of the lures: It improved correct rejection of unstudied lures but increased false memory for critical lures (i.e., lures associated with words studied previously). Thus, increased salience triggered by positive valence may disrupt memory accuracy in older adults when discriminating among similar events. These findings likely reflect a source memory deficit due to decreased efficiency in cognitive control processes with aging. PMID:18573005

  10. Blocking Mimicry Makes True and False Smiles Look the Same

    PubMed Central

    Rychlowska, Magdalena; Cañadas, Elena; Wood, Adrienne; Krumhuber, Eva G.; Fischer, Agneta; Niedenthal, Paula M.

    2014-01-01

    Recent research suggests that facial mimicry underlies accurate interpretation of subtle facial expressions. In three experiments, we manipulated mimicry and tested its role in judgments of the genuineness of true and false smiles. Experiment 1 used facial EMG to show that a new mouthguard technique for blocking mimicry modifies both the amount and the time course of facial reactions. In Experiments 2 and 3, participants rated true and false smiles either while wearing mouthguards or when allowed to freely mimic the smiles with or without additional distraction, namely holding a squeeze ball or wearing a finger-cuff heart rate monitor. Results showed that blocking mimicry compromised the decoding of true and false smiles such that they were judged as equally genuine. Together the experiments highlight the role of facial mimicry in judging subtle meanings of facial expressions. PMID:24670316

  11. False carina: A distinct variant of tracheal bronchus.

    PubMed

    Rahmanian, Ronak; Zheng, Jack; Chadha, Neil K; Kozak, Frederick K; Campbell, Andrew I M; Ludemann, Jeffrey P

    2015-04-01

    Tracheal-bronchus is an aberrant bronchus arising from the lateral tracheal wall, superior to the carina. A "False-carina" can be classified as a sub-type. This clinical entity will be defined and the clinical presentation, diagnosis and management of five patients with variations of the anatomical definition of a False-carina, identified at our institution, will be reviewed. Congenital bronchial abnormalities, including False-carina, have important implications in the overall management of the airway. Management can range from expectant in asymptomatic patients to surgical intervention in cases of recurrent respiratory infections. Awareness and understanding of this clinical entity allows for timely investigation, diagnosis and appropriate intervention. PMID:25683591

  12. Effectiveness of false correction strategy on science reading comprehension

    NASA Astrophysics Data System (ADS)

    Ghent, Cynthia Anne

    False-correction reading strategy theoretically prompted college students to activate their prior knowledge when provided false statements linked to a portion of their biology textbook. This strategy is based in elaborative interrogation theory, which suggests that prompting readers to answer interrogatives about text students are reading increases their comprehension of that text. These interrogatives always asked "why" statements pulled from a text, one sentence in length, were "true." True statements in this study based on a text were converted by the experimenter into false statements, one sentence in length. Students were requested to rewrite each statement (n=12) on average every 200 words in a text as they were reading, converting each false statement into a true statement. These students outperformed other students requested to reread the same biology text twice (an established placebo-control strategy). These students, in turn, outperformed still other students reading an unrelated control text taken from the same textbook used only to establish a prior knowledge baseline for all students included in this study. Students participating in this study were enrolled students in an undergraduate introductory general biology course designed for non-majors. A three-group, posttest-only, randomized experimental control-group design was used to prevent pretest activation of students' prior knowledge thus increasing chances of producing evidence of false-correction effectiveness and to begin augmenting potential generalizability to science classrooms. Students' (n=357) general biology knowledge, verbal ability, and attempts to use the false correction strategy were collected and analyzed. Eight of the participants were interviewed by the researcher in a first attempt in this domain to collect data on participants' points of view about the strategy. The results of this study are not yet recommended for use in authentic school settings as further research is indicated.

  13. [False traumatic aneurysm of the ulnar artery in a teenager].

    PubMed

    Nour, M; Talha, H; El Idrissi, R; Lahraoui, Y; Ouazzani, L; Oubejja, H; Erraji, M; Zerhouni, H; Ettayebi, F

    2014-12-01

    Most aneurysms of hand arteries are traumatic. It is a generally rare unrecognized pathology. Complications are serious (embolism and thromboses of interdigital arteries). Two main causes can be recalled: acute trauma, with development of a false aneurysm; repeated microtrauma (hand hammer syndrome), with occurrence of an arterial dysplasic aneurysm. The diagnosis is based on the presence of a pulsatile mass, with finger dysesthesia, unilateral Raynaud's phenomenon. It is confirmed by duplex Doppler. Arteriography is necessary but can be replaced by an angio-MR. We report a case of false traumatic aneurysm of the ulnar artery in a teenager. This case illustrates this rare condition and opens discussion on therapeutic options. PMID:24970785

  14. Horizons and Tunneling in the Euclidean False Vacuum

    E-print Network

    Kate Marvel; Neil Turok

    2007-12-17

    In the thin-wall approximation, the decay of a gravitating false vacuum to a lower-energy state is affected by the cosmological horizon structure in both spaces. The nucleation radius of a bubble of true vacuum depends on the surface tension of its boundary and equals the false vacuum cosmological horizon at a critical tension. We argue that there is no tunneling instanton solution beyond the critical tension and argue that there is therefore a bound on allowed membrane tension in theories which rely on semiclassical tunneling to relax the cosmological constant.

  15. Arterial false aneurysm in the groin following endovenous laser ablation.

    PubMed

    Ostler, Alexandra E; Holdstock, Judy M; Harrison, Charmaine C; Whiteley, Mark S

    2015-04-01

    Endovenous laser ablation is a minimally invasive catheter-based procedure for the treatment of varicose veins. The procedure involves injecting tumescent anaesthesia around the catheterised truncal vein, before thermal ablation by the laser. We report a case of a false aneurysm arising from a branch of the inferior epigastric artery, following endovenous laser ablation. The false aneurysm was thought to be caused by injury to the artery by the needle used to inject the tumescent anaesthesia. Although a rare complication, newer tumescentless techniques such as mechanicochemical ablation and cyanoacrylate glue would prevent such a complication. PMID:24255091

  16. Negative acoustic index metamaterial

    NASA Astrophysics Data System (ADS)

    Fok, L.; Zhang, X.

    2011-06-01

    Acoustic metamaterials utilizing periodic deep subwavelength resonators can attain negative acoustic properties unavailable in nature. We have developed a negative acoustic index metamaterial for water that combines Helmholtz and rod-spring resonators to control effective bulk modulus and mass density, respectively. Effective properties extracted from full-wave simulations of our metamaterial show that negative real components of bulk modulus and density occur simultaneously, resulting in a negative real component of the acoustic index. Experimental measurements on a sample of this metamaterial confirm that the real components of the acoustic index and bulk modulus attain negative values, but the density does not become negative. The primary causes of this are identified and potential solutions are presented.

  17. NEGATIVE SYMPTOMS IN DEPRESSION

    PubMed Central

    Chaturvedi, Santosh K.; Sarmukaddam, Sanjeev

    1985-01-01

    SUMMARY Negative symptoms have been assessed in 34 cases of major depression (ROC) using the scale for assessment of negative symptoms. Negative symptoms were found to be quite frequently observed in these cases; common negative symptoms were inability to enjoy recreational interests and activities (76%), feelings of anhedonia (64.7%) and physical anergia (55.9%). Poverty of speech was found to be more in younger patients (P < .001). Avolition was seen more frequently in unmarried (P < .05) patients. No other signiticant correlation was noticed between demographic variables and negative symptoms. The implications of evaluating negative symptoms systematically in depressives are for future research especially for prognostication, treatment responses and classification of depression based on such symptoms. PMID:21927088

  18. Fermions Tunneling from Apparent Horizon of FRW Universe

    E-print Network

    Ran Li; Ji-Rong Ren; Dun-Fu Shi

    2008-12-22

    In the paper [arXiv:0809.1554], the scalar particles' Hawking radiation from the apparent horizon of Friedmann-Robertson-Walker(FRW) universe was investigated by using the tunneling formalism. They obtained the Hawking temperature associated with the apparent horizon, which was extensively applied in investigating the relationship between the first law of thermodynamics and Friedmann equations. In this paper, we calculate Fermions' Hawking radiation from the apparent horizon of FRW universe via tunneling formalism. Applying WKB approximation to the general covariant Dirac equation in FRW spacetime background, the radiation spectrum and Hawking temperature of apparent horizon are correctly recovered, which supports the arguments presented in the paper [arXiv:0809.1554].

  19. Apparent Ionic Charge in Electrolyte and Polyelectrolyte Solutions

    ERIC Educational Resources Information Center

    Magdelenat, H.; And Others

    1978-01-01

    Compares average displacements of charged particles under thermal motion alone with those obtained by the action of an external electric field to develop a concept of "apparent charge" to approximate actual structural charge in an electrolyte solution. (SL)

  20. Introduction Alzheimer's disease (AD) has an apparent multifactoral

    E-print Network

    Graves, Michael V.

    'S DISEASE F. TCHANTCHOU, M. GRAVES, D. ORTIZ, A. CHAIntroduction Alzheimer's disease (AD) has an apparent multifactoral etiology that encompasses including dementia, impaired cognition, depression, psychosis, AD and Parkinson's disease (2). Folate- and B

  1. Motion Processing and From-from-Apparent-Motion in Infancy

    E-print Network

    Hirshkowitz, Amy

    2014-08-05

    , Khorram-Sefat, Muckli, Hacker, & Singer, 1998; Liu, Slotnick, & Yantis, 2004). Given that infants in all of the conditions had to construct the motion (apparent motion) to extract the shape, having the luminance information accessible in the same dorsal...

  2. Human vertebral body apparent and hard tissue stiffness

    Microsoft Academic Search

    Fu J. Hou; Susan M. Lang; Susan J. Hoshaw; David A. Reimann; David P. Fyhrie

    1998-01-01

    Cancellous bone apparent stiffness and strength are dependent upon material properties at the tissue level and trabecular architecture. Microstructurally accurate, large-scale finite element (LS-FE) models were used to predict the experimental apparent stiffness of human vertebral cancellous bone and to estimate the trabecular hard tissue stiffness. Twenty-eight LS-FE models of cylindrical human vertebral cancellous bone specimens (8mm in diameter, 9.5mm

  3. Negative Ion Density Fronts

    SciTech Connect

    Igor Kaganovich

    2000-12-18

    Negative ions tend to stratify in electronegative plasmas with hot electrons (electron temperature Te much larger than ion temperature Ti, Te > Ti ). The boundary separating a plasma containing negative ions, and a plasma, without negative ions, is usually thin, so that the negative ion density falls rapidly to zero-forming a negative ion density front. We review theoretical, experimental and numerical results giving the spatio-temporal evolution of negative ion density fronts during plasma ignition, the steady state, and extinction (afterglow). During plasma ignition, negative ion fronts are the result of the break of smooth plasma density profiles during nonlinear convection. In a steady-state plasma, the fronts are boundary layers with steepening of ion density profiles due to nonlinear convection also. But during plasma extinction, the ion fronts are of a completely different nature. Negative ions diffuse freely in the plasma core (no convection), whereas the negative ion front propagates towards the chamber walls with a nearly constant velocity. The concept of fronts turns out to be very effective in analysis of plasma density profile evolution in strongly non-isothermal plasmas.

  4. Negative ion density fronts

    NASA Astrophysics Data System (ADS)

    Kaganovich, Igor

    2001-05-01

    Negative ions tend to stratify in electronegative plasmas with hot electrons (electron temperature Te much larger than ion temperature Ti, Te?Ti). The boundary separating a plasma containing negative ions, and a plasma without negative ions, is usually thin so that the negative ion density falls rapidly to zero—forming a negative ion density front. Theoretical, experimental, and numerical results giving the spatio-temporal evolution of negative ion density fronts during plasma ignition, the steady state, and extinction (afterglow) are reviewed. During plasma ignition, negative ion fronts are the result of the break of smooth plasma density profiles during nonlinear convection. In a steady-state plasma, the fronts are boundary layers with steepening of ion density profiles due to nonlinear convection also. But during plasma extinction, the ion fronts are of a completely different nature. Negative ions diffuse freely in the plasma core (no convection), whereas the negative ion front propagates towards the chamber walls with a nearly constant velocity. The concept of fronts turns out to be very effective in the analysis of plasma density profile evolution in strongly nonisothermal plasmas.

  5. False Paradoxes of Superposition in Electric and Acoustic Waves.

    ERIC Educational Resources Information Center

    Levine, Richard C.

    1980-01-01

    Corrected are several misconceptions concerning the apparently "missing" energy that results when acoustic or electromagnetic waves cancel by destructive interference and the wave impedance reflected to the sources of the wave energy changes so that the input power is reduced. (Author/CS)

  6. The D-Dimer Test for Deep Venous Thrombosis: Gold Standards and Bias in Negative Predictive Value

    Microsoft Academic Search

    John T. Philbrick; Steven Heim

    Background: Because venous ultrasound (US) fails to fully image the calf veins, there is the potential for US gold standard studies to classify patients with calf deep venous thrombosis (DVT) in the nondiseased category, causing bias in test index calculations. A false increase in negative predictive value (NPV) is especially likely because calf DVT false-negative tests will be counted in

  7. An Improved Comprehensive Model for the Apparent Viscosity of Blood

    NASA Astrophysics Data System (ADS)

    Jacobitz, Frank; Anderson, Spencer

    2008-11-01

    An improved comprehensive model for the apparent viscosity of blood is developed and used in simulations of the microcirculation in capillary bundles of rat spinotrapezius muscle fascia. In the microcirculation, the apparent viscosity of blood depends on the local vessel diameter, hematocrit, and shear rate. The proposed comprehensive model extends the apparent viscosity model developed by Pries, Secomb, Gaehtgens, and Gross (Circulation Research, 67, 826-834, 1990), which describes the effect of vessel diameter and hematocrit on the apparent viscosity. A shear thinning term is developed using the experimental data of Lipowsky, Usami, and Chien (Microvascular Research, 19, 297-319, 1980). Curve fits of this data can be combined with equations given in the Pries et al. work to create a system of equations that can be used to find the shear thinning factor. The simulations based on the improved apparent viscosity model use realistic vessel topology for the microvasculature, reconstructed from microscope images of tissue samples, and consider passive and active vessel properties. The numerical method is based on a Hagen-Poiseuille balance in the microvessels and a sparse matrix solver is used to obtain the solution. It was found that the inclusion of the shear factor decreases the overall flowrate in the capillary bundle. Many vessel connections in the fascia are characterized by relatively low shear rates and therefore increased apparent viscosity.

  8. A study of oligoclonal band negative multiple sclerosis

    Microsoft Academic Search

    A Z Zeman; D Kidd; B N McLean; M A Kelly; D A Francis; D H Miller; B E Kendall; P Rudge; E J Thompson; W I McDonald

    1996-01-01

    OBJECTIVES--To determine whether oligoclonal band (OCB) negative multiple sclerosis is a reliable diagnosis and, if so, whether it has a distinctive prognosis. METHODS--Retrospective and matched prospective comparison of the clinical and laboratory features of patients with clinical definite multiple sclerosis with and without intrathecal synthesis of oligoclonal IgG. RESULTS--Thirty four patients were identified with apparent OCB negative clinically definite multiple

  9. A Demonstration of Regression False Positive Selection in Data Mining

    ERIC Educational Resources Information Center

    Pinder, Jonathan P.

    2014-01-01

    Business analytics courses, such as marketing research, data mining, forecasting, and advanced financial modeling, have substantial predictive modeling components. The predictive modeling in these courses requires students to estimate and test many linear regressions. As a result, false positive variable selection ("type I errors") is…

  10. 7 CFR 48.5 - False report or statement.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ...AGRICULTURE FOR THE ENFORCEMENT OF THE PRODUCE AGENCY ACT Violations § 48.5 False...or statement. Any person receiving produce in interstate commerce or in the District...statement to the person from whom such produce was received concerning the...

  11. Young Children's Emerging Ability to Make False Statements

    ERIC Educational Resources Information Center

    Ahern, Elizabeth C.; Lyon, Thomas D.; Quas, Jodi A.

    2011-01-01

    This study examined the origins of children's ability to make consciously false statements, a necessary component of lying. Children 2 to 5 years of age were rewarded for claiming that they saw a picture of a bird when viewing pictures of fish. They were asked outcome questions ("Do you win/lose?"), recognition questions ("Do you have a…

  12. 12. VIEW OF SPACE BETWEEN EAST FALSE PARTITION WALL IN ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    12. VIEW OF SPACE BETWEEN EAST FALSE PARTITION WALL IN CLEAN ROOM (102) AND EAST WALL OF VEHICLE SUPPORT BUILDING SHOWING PREFILTER NEAR SOUTH WALL - Vandenberg Air Force Base, Space Launch Complex 3, Vehicle Support Building, Napa & Alden Roads, Lompoc, Santa Barbara County, CA

  13. Detecting False Positives in Multielement Designs: Implications for Brief Assessments

    ERIC Educational Resources Information Center

    Bartlett, Sara M.; Rapp, John T.; Henrickson, Marissa L.

    2011-01-01

    The authors assessed the extent to which multielement designs produced false positives using continuous duration recording (CDR) and interval recording with 10-s and 1-min interval sizes. Specifically, they created 6,000 graphs with multielement designs that varied in the number of data paths, and the number of data points per data path, using a…

  14. Age Differences in False Recognition Using a Forced Choice Paradigm

    Microsoft Academic Search

    2000-01-01

    Recent findings suggest that older adults may be more susceptible to false recognition responses than younger adults because of age differences in gist-based processing at both encoding and retrieval. It has been suggested that age differences in the quality of memory representations that result from this age-related reliance on gist processing can produce age differences in response criteria, with older

  15. Looking for Childhood Schizophrenia: Case Series of False Positives.

    ERIC Educational Resources Information Center

    Stayer, Catherine; Sporn, Alexandra; Gogtay, Nitin; Tossell, Julia; Lenane, Marge; Gochman, Peter; Rapoport, Judith L.

    2004-01-01

    Extensive experience with the diagnosis of childhood-onset schizophrenia indicates a high rate of false positives. Most mislabeled patients have chronic disabling, affective, or behavioral disorders. The authors report the cases of three children who passed stringent initial childhood-onset schizophrenia "screens" but had no chronic psychotic…

  16. Matched False-Belief Performance during Verbal and Nonverbal Interference

    ERIC Educational Resources Information Center

    Dungan, James; Saxe, Rebecca

    2012-01-01

    Language has been shown to play a key role in the development of a child's theory of mind, but its role in adult belief reasoning remains unclear. One recent study used verbal and nonverbal interference during a false-belief task to show that accurate belief reasoning in adults necessarily requires language (Newton & de Villiers, 2007). The…

  17. Counterfactual Conditionals and False Belief: A Developmental Dissociation

    ERIC Educational Resources Information Center

    Perner, Josef; Sprung, Manuel; Steinkogler, Bettina

    2004-01-01

    The objective of this study was to explore factors that affect the difficulty of counterfactual reasoning in 3-5-year-old children and to shed light on the reason why counterfactual reasoning relates to understanding false belief [Cognitive Development, 13 (1998) 73-90]. Using travel scenarios, the difference between simple scenarios, in which…

  18. Hyperspectral matched filter with false-alarm mitigation

    NASA Astrophysics Data System (ADS)

    Dipietro, Robert S.; Manolakis, Dimitris G.; Lockwood, Ronald B.; Cooley, Thomas; Jacobson, John

    2012-01-01

    One of the fundamental challenges for a hyperspectral imaging surveillance system is the detection of sub-pixel objects in background clutter. The background surrounding the object, which acts as interference, provides the major obstacle to successful detection. One algorithm that is widely used in hyperspectral detection and successfully suppresses the background in many situations is the matched filter detector. However, the matched filter also produces false alarms in many situations. We use three simple and well-established concepts--the target-background replacement model, the matched filter, and Mahalanobis distance--to develop the matched filter with false alarm mitigation (MF-FAM), a dual-threshold detector capable of eliminating many matched filter false alarms. We compare this algorithm to the mixture tuned matched filter (MTMF), a popular approach to matched filter false alarm mitigation found in the ENVI® software environment. The two algorithms are shown to produce nearly identical results using real hyperspectral data, but the MF-FAM is shown to be operationally, computationally, and theoretically simpler than the MTMF.

  19. Fermat Numbers: A False Conjecture Leads to Fun and Fascination

    E-print Network

    Sethuraman, Al

    Fermat Numbers: A False Conjecture Leads to Fun and Fascination B. A. Sethuraman February 13, 2013 1 Introduction The French mathematician Pierre de Fermat (1601­1665) was a veritable giant of number fea- tured his work: the first issue reviewed a book ([1]) on the history of what is known as "Fermat

  20. Narrative dependency and the false belief task in autism

    Microsoft Academic Search

    Evelyn McGregor; Mark Bennett

    2008-01-01

    Several studies have used a cognitive approach to teaching people with autism to pass false belief tasks with a broader aim of developing theory of mind abilities. However, these tasks have certain executive features that may influence performance on the tasks and the potential for generalization. The study examines the influence of narrative support and language level on the ability

  1. Bogus Concerns about the False Prototype Enhancement Effect

    ERIC Educational Resources Information Center

    Homa, Donald; Hout, Michael C.; Milliken, Laura; Milliken, Ann Marie

    2011-01-01

    Two experiments addressed the mechanism responsible for the false prototype effect, the phenomenon in which a prototype gradient can be obtained in the absence of learning. Previous demonstrations of this effect have occurred solely in a single-category paradigm in which transfer patterns are assigned or not to the learning category. We tested the…

  2. Spectral and spatial analysis of false alarms in background data

    Microsoft Academic Search

    Abhishek Sanaka; Shivakar Vulli; Sanjeev Agarwal; Richard Ess; Anh Trang

    2009-01-01

    A significant amount of background data was collected as part of May 2005 tests at an arid site for airborne minefield detection. An extensive library of the target chips for MSI (four bands) and MWIR sensors for false alarms and mines was created from this data collection, as discussed in another paper in the same proceeding. In this paper we

  3. Context Effects and False Memory for Alcohol Words in Adolescents

    PubMed Central

    Zack, Martin; Sharpley, Justin; Dent, Clyde W.; Stacy, Alan W.

    2011-01-01

    This study assessed incidental recognition of Alcohol and Neutral words in adolescents who encoded the words under distraction. Participants were 171 (81 male) 10th grade students, ages 14–16 (M = 15.1) years. Testing was conducted by telephone: Participants listened to a list containing Alcohol and Neutral (Experimental – Group E, n = 92) or only Neutral (Control – Group C, n = 79) words, while counting backwards from 200 by two’s. Recognition was tested immediately thereafter. Group C exhibited higher false recognition of Neutral than Alcohol items, whereas Group E displayed equivalent false rates for both word types. The reported number of alcohol TV ads seen in the past week predicted higher false recognition of Neutral words in Group C and of Alcohol words in Group E. False memory for Alcohol words in Group E was greater in males and high anxiety sensitive participants. These context-dependent biases may contribute to exaggerations in perceived drinking norms previously found to predict alcohol misuse in young drinkers. PMID:19081200

  4. Context effects and false memory for alcohol words in adolescents.

    PubMed

    Zack, Martin; Sharpley, Justin; Dent, Clyde W; Stacy, Alan W

    2009-03-01

    This study assessed incidental recognition of Alcohol and Neutral words in adolescents who encoded the words under distraction. Participants were 171 (87 male) 10th grade students, ages 14-16 (M=15.1) years. Testing was conducted by telephone: Participants listened to a list containing Alcohol and Neutral (Experimental--Group E, n=92) or only Neutral (Control--Group C, n=79) words, while counting backwards from 200 by two's. Recognition was tested immediately thereafter. Group C exhibited higher false recognition of Neutral than Alcohol items, whereas Group E displayed equivalent false rates for both word types. The reported number of alcohol TV ads seen in the past week predicted higher false recognition of Neutral words in Group C and of Alcohol words in Group E. False memory for Alcohol words in Group E was greater in males and high anxiety sensitive participants. These context-dependent biases may contribute to exaggerations in perceived drinking norms previously found to predict alcohol misuse in young drinkers. PMID:19081200

  5. Do 10-Month-Old Infants Understand Others' False Beliefs?

    ERIC Educational Resources Information Center

    Luo, Yuyan

    2011-01-01

    As adults, we know that others' mental states, such as beliefs, guide their behavior and that these mental states can deviate from reality. Researchers have examined whether young children possess adult-like theory of mind by focusing on their understanding about others' false beliefs. The present research revealed that 10-month-old infants seemed…

  6. Observed changes in false springs over the contiguous United States

    NASA Astrophysics Data System (ADS)

    Peterson, Alexander G.; Abatzoglou, John T.

    2014-03-01

    Climate warming fosters an earlier spring green-up that may bring potential benefits to agricultural systems. However, advances in green-up timing may leave early stage vegetation growth vulnerable to cold damage when hard freezes follow green-up resulting in a false spring. Spatiotemporal patterns of green-up dates, last spring freezes, and false springs were examined across the contiguous United States from 1920 to 2013. Results indicate widespread earlier green-up and last spring freeze dates over the period. Observed changes in these dates were asymmetric with the last spring freeze date advancing to earlier in the year relative to green-up date. Although regionally variable, these changes resulted in a reduction in false springs, notably over the past 20 years, except across the intermountain western United States where the advance in green-up timing outpaced that of the last spring freeze. A sensitivity experiment shows that observed decreases in false springs are consistent with a warming climate.

  7. Validity of False Belief Tasks in Blind Children

    ERIC Educational Resources Information Center

    Brambring, Michael; Asbrock, Doreen

    2010-01-01

    Previous studies have reported that congenitally blind children without any additional impairment reveal a developmental delay of at least 4 years in perspective taking based on testing first-order false-belief tasks. These authors interpret this delay as a sign of autism-like behavior. However, the delay may be caused by testing blind children…

  8. False Choices: Why School Vouchers Threaten Our Children's Future.

    ERIC Educational Resources Information Center

    Lowe, Robert, Ed.; Miner, Barbara, Ed.

    1992-01-01

    A voucher system of schooling would destroy the few democratic gains made in public education in recent years, worsen inequalities that already permeate education, and block opportunities for meaningful reform. Articles included in this special issue are: (1) an introduction, "Why We Are Publishing False Choices" ("Rethinking Schools" Editorial…

  9. A Competitive Nonverbal False Belief Task for Children and Apes

    ERIC Educational Resources Information Center

    Krachun, Carla; Carpenter, Malinda; Call, Josep; Tomasello, Michael

    2009-01-01

    A nonverbal false belief task was administered to children (mean age 5 years) and two great ape species: chimpanzees ("Pan troglodytes") and bonobos ("Pan paniscus"). Because apes typically perform poorly in cooperative contexts, our task was competitive. Two versions were run: in both, a human competitor witnessed an experimenter hide a reward in…

  10. Matched False-Belief Performance During Verbal and Nonverbal Interference

    E-print Network

    Saxe, Rebecca

    ). In one such study, exposure to deceptive scenarios without language did not improve false 2011; received in revised form 27 September 2011; accepted 3 October 2011 Abstract Language has been shown to play a key role in the development of a child's theory of mind, but its role in adult belief

  11. Distinguishing Data Transience from False Injection in Sensor Networks

    E-print Network

    Qiao, Daji

    and report a simple statistical digest in addition to the current sensed reading. SSTF is a two-tier system, due to the presence of adversaries who intend to disrupt the functioning of the system, it becomes imperative to shield our system from false data injection attacks. We propose a novel secure statistical

  12. Dynamically removing false features in pyramidal lucas-kanade registration.

    PubMed

    Niu, Yan; Xu, Zhiwen; Che, Xiangjiu

    2014-08-01

    Pyramidal Lucas-Kanade (LK) optical flow is a real-time registration technique widely employed by a variety of cutting edge consumer applications. Traditionally, the LK algorithm is applied selectively to image feature points that have strong spatial variation, which include outliers in textured areas. To detect and discard the falsely selected features, previous methods generally assess the goodness of each feature after the flow computation is completed. Such a screening process incurs additional cost. This paper provides a handy (but not obvious) tool for the users of the LK algorithm to remove false features without degrading the algorithm's efficiency. We propose a confidence predictor, which evaluates the ill-posedness of an LK system directly from the underlying data, at a cost lower than solving the system. We then incorporate our confidence predictor into the course-to-fine LK registration to dynamically detect false features and terminate their flow computation at an early stage. This improves the registration accuracy by preventing the error propagation and maintains (or increases) the computation speed by saving the runtime on false features. Experimental results on state-of-the-art benchmarks validate that our method is more accurate and efficient than related works. PMID:24956365

  13. Siblings, Language, and False Belief in Low-Income Children

    ERIC Educational Resources Information Center

    Tompkins, Virginia; Farrar, M. Jeffrey; Guo, Ying

    2013-01-01

    The authors examined the relationship between number of siblings and false belief understanding (FBU) in 94 low-income 4-5-year-olds. Previous research with middle-income children has shown a positive association between number of siblings and FBU. However, it is unclear whether having multiple siblings in low-income families is related to better…

  14. Replication levels, false presences and the estimation of the presence/absence from eDNA metabarcoding data.

    PubMed

    Ficetola, Gentile F; Pansu, Johan; Bonin, Aurélie; Coissac, Eric; Giguet-Covex, Charline; De Barba, Marta; Gielly, Ludovic; Lopes, Carla M; Boyer, Frédéric; Pompanon, François; Rayé, Gilles; Taberlet, Pierre

    2015-05-01

    Environmental DNA (eDNA) metabarcoding is increasingly used to study the present and past biodiversity. eDNA analyses often rely on amplification of very small quantities or degraded DNA. To avoid missing detection of taxa that are actually present (false negatives), multiple extractions and amplifications of the same samples are often performed. However, the level of replication needed for reliable estimates of the presence/absence patterns remains an unaddressed topic. Furthermore, degraded DNA and PCR/sequencing errors might produce false positives. We used simulations and empirical data to evaluate the level of replication required for accurate detection of targeted taxa in different contexts and to assess the performance of methods used to reduce the risk of false detections. Furthermore, we evaluated whether statistical approaches developed to estimate occupancy in the presence of observational errors can successfully estimate true prevalence, detection probability and false-positive rates. Replications reduced the rate of false negatives; the optimal level of replication was strongly dependent on the detection probability of taxa. Occupancy models successfully estimated true prevalence, detection probability and false-positive rates, but their performance increased with the number of replicates. At least eight PCR replicates should be performed if detection probability is not high, such as in ancient DNA studies. Multiple DNA extractions from the same sample yielded consistent results; in some cases, collecting multiple samples from the same locality allowed detecting more species. The optimal level of replication for accurate species detection strongly varies among studies and could be explicitly estimated to improve the reliability of results. PMID:25327646

  15. Effects of false feedback on affect, cognition, behavior, and postevent processing: the mediating role of self-focused attention.

    PubMed

    Makkar, Steve R; Grisham, Jessica R

    2013-03-01

    Current social phobia models (e.g., Clark & Wells, 1995; Leary & Kowalski, 1995) postulate that socially anxious individuals negatively appraise their anxiety sensations (e.g., sweating, heart racing, blushing) as evidence of poor social performance, and thus fear these anxiety symptoms will be noticed and judged negatively by others. Consequently, they become self-focused and hypervigilant of these sensations and use them to judge how they appear to others. To test this model, high (N=41) and low (N=38) socially anxious participants were shown false physiological feedback regarding an increase or decrease in heart rate prior to and during an impromptu speech task. Relative to participants who observed a false heart rate decrease, those in the increase condition reported higher levels of negative affect, more negative performance appraisals, and more frequent negative ruminative thoughts, and these effects were mediated by an increase in self-focused attention. The unhelpful effects of the physiological feedback were not specific to high socially anxious participants. The results have implications for current cognitive models as well as the treatment of social phobia. PMID:23312431

  16. Positive and negative perfectionism

    Microsoft Academic Search

    L. A. Terry-Short; R. Glynn Owens; P. D. Slade; M. E. Dewey

    1995-01-01

    Previous research into perfectionism has focused on clinical populations resulting in a bias towards a negativistic, pathologically inclined conceptualization. The present study investigated the possibility of distinguishing aspects of perfectionism on the basis of perceived consequences, mirroring a behavioural distinction between positive and negative reinforcement. A 40-item questionnaire, designed to measure perfectionism defined in terms of both positive and negative

  17. Communicating with Negative People

    Microsoft Academic Search

    Adriana Vintean

    2007-01-01

    We all must have been negative at work at one time or another and most of us didn't like to be that way. For some people it is a way of being. Some people seem to flourish in a negative atmosphere. Often people defend their right to be nasty as their legitimate duty. Do Emergency Communications Centers have an over-abundance

  18. Oxygen Stimulation of Apparent Photosynthesis in Flaveria linearis1

    PubMed Central

    Brown, R. Harold; Bouton, Joseph H.; Evans, Philip T.

    1986-01-01

    A plant was found in the C3-C4 intermediate species, Flaveria linearis, in which apparent photosynthesis is stimulated by atmospheric O2 concentrations. A survey of 44 selfed progeny of the plant showed that the O2 stimulation of apparent photosynthesis was passed on to the progeny. When leaves equilibrated at 210 milliliters per liter O2 were transferred to 20 milliliters per liter O2 apparent photosynthesis was initially stimulated, but gradually declined so that at 30 to 40 minutes the rate was only about 80 to 85% of that at 210 milliliters per liter O2. Switching from 20 to 210 milliliters per liter caused the opposite transition in apparent photosynthesis. All other plants of F. linearis reached steady rates within 5 minutes after switching O2 that were 20 to 24% lower in 210 than in 20 milliliters per liter O2. At low intercellular CO2 concentrations and low irradiances, O2 inhibition of apparent photosynthesis of the aberrant plant was similar to that in normal plants, but at an irradiance of 2 millimoles quanta per square meter per second and near 300 microliters per liter CO2 apparent photosynthesis was consistently higher at 210 than at 20 milliliters per liter O2. In morphology and leaf anatomy, the aberrant plant is like the normal plants in F. linearis. The stimulation of apparent photosynthesis at air levels of O2 in the aberrant plant is similar to other literature reports on observations with C3 plants at high CO2 concentrations, high irradiance and/or low temperatures, and may be related to limitation of photosynthesis by triose phosphate utilization. PMID:16664777

  19. Nearly extremal apparent horizons in simulations of merging black holes

    NASA Astrophysics Data System (ADS)

    Lovelace, Geoffrey; Scheel, Mark A.; Owen, Robert; Giesler, Matthew; Katebi, Reza; Szilágyi, Béla; Chu, Tony; Demos, Nicholas; Hemberger, Daniel A.; Kidder, Lawrence E.; Pfeiffer, Harald P.; Afshari, Nousha

    2015-03-01

    The spin angular momentum S of an isolated Kerr black hole is bounded by the surface area A of its apparent horizon: 8? S?slant A, with equality for extremal black holes. In this paper, we explore the extremality of individual and common apparent horizons for merging, rapidly spinning binary black holes. We consider simulations of merging black holes with equal masses M and initial spin angular momenta aligned with the orbital angular momentum, including new simulations with spin magnitudes up to S/{{M}2}=0.994. We measure the area and (using approximate Killing vectors) the spin on the individual and common apparent horizons, finding that the inequality 8? S\\lt A is satisfied in all cases but is very close to equality on the common apparent horizon at the instant it first appears. We also evaluate the Booth-Fairhurst extremality, whose value for a given apparent horizon depends on the scaling of the horizon’s null normal vectors. In particular, we introduce a gauge-invariant lower bound on the extremality by computing the smallest value that Booth and Fairhurst’s extremality parameter can take for any scaling. Using this lower bound, we conclude that the common horizons are at least moderately close to extremal just after they appear. Finally, following Lovelace et al (2008 Phys. Rev. D 78 084017), we construct quasiequilibrium binary-black hole initial data with ‘overspun’ marginally trapped surfaces with 8? S\\gt A. We show that the overspun surfaces are indeed superextremal: our lower bound on their Booth-Fairhurst extremality exceeds unity. However, we confirm that these superextremal surfaces are always surrounded by marginally outer trapped surfaces (i.e., by apparent horizons) with 8? S\\lt A. The extremality lower bound on the enclosing apparent horizon is always less than unity but can exceed the value for an extremal Kerr black hole.

  20. False ventricular tachycardia alarm suppression in the ICU based on the discrete wavelet transform in the ECG signal.

    PubMed

    Salas-Boni, Rebeca; Bai, Yong; Harris, Patricia Rae Eileen; Drew, Barbara J; Hu, Xiao

    2014-01-01

    Over the past few years, reducing the number of false positive cardiac monitor alarms (FA) in the intensive care unit (ICU) has become an issue of the utmost importance. In our work, we developed a robust methodology that, without the need for additional non-ECG waveforms, suppresses false positive ventricular tachycardia (VT) alarms without resulting in false negative alarms. Our approach is based on features extracted from the ECG signal 20 seconds prior to a triggered alarm. We applied a multi resolution wavelet transform to the ECG data 20seconds prior to the alarm trigger, extracted features from appropriately chosen scales and combined them across all available leads. These representations are presented to a L1-regularized logistic regression classifier. Results are shown in two datasets of physiological waveforms with manually assessed cardiac monitor alarms: the MIMIC II dataset, where we achieved a false alarm (FA) suppression of 21% with zero true alarm (TA) suppression; and a dataset compiled by UCSF and General Electric, where a 36% FA suppression was achieved with a zero TA suppression. The methodology described in this work could be implemented to reduce the number of false monitor alarms in other arrhythmias. PMID:25172188

  1. The use of surrogate species in risk assessment: using life history data to safeguard against false negatives.

    PubMed

    Banks, John E; Ackleh, Azmy S; Stark, John D

    2010-02-01

    The use of surrogate species is an important tool in predicting the effects of management decisions or the establishment of protective measures for endangered/threatened species. While relying on a handful of model species to predict the fate of scores of distantly related target species has been criticized, a quantitative measure linking life history traits and population predictions has been sorely missing. We derive here a closed-form expression aimed at determining conditions under which sublethal effects of a toxicant on surrogate species population outcomes will reliably predict outcomes of target (listed) species. We develop a critical threshold in fecundity reduction above which the surrogate species outcomes indicate positive population growth, while the listed species is driven to extinction. Thus we have established a means of determining conditions under which we are prone to making a "Type II" error in assessing ecological risk using surrogate species. Finally, we use the derived expression and life history data to compare outcomes from four different commonly used fish surrogate species (round goby, fathead minnow, smallmouth bass, cutthroat trout) and their target listed species (Chinook and Coho salmon). We illustrate that all four surrogate species fail to predict population outcomes for the listed species in cases of as little as 15% fecundity reduction due to toxicant exposure. Furthermore, surrogate species reliability is a function of toxicant level, so that some species are reliable at some levels but not at others. We discuss the implications of these findings, and outline further analyses that occur as a natural extension of the criteria developed here. PMID:20136742

  2. Using mass spectrometry to detect hydrolysed gluten in beer that is responsible for false negatives by ELISA.

    PubMed

    Colgrave, Michelle L; Goswami, Hareshwar; Blundell, Malcolm; Howitt, Crispin A; Tanner, Gregory J

    2014-11-28

    Gluten is the collective name for a class of proteins found in wheat, rye, barley and oats. Eating gluten triggers an inappropriate auto-immune reaction in ?70 million people globally affected by coeliac disease, where the gut reacts to gluten proteins and this triggers an immune response, resulting in intestinal inflammation and damage. Gluten-free foods are now commonplace, however, it is difficult to accurately determine the gluten content of products claiming to be gluten-free using current methodologies as the antibodies are non-specific, show cross-reactivity and have different affinities for the different classes of gluten. The measurement of gluten in processed products is further confounded by modifications to the proteins that occur during processing and in some case hydrolysis of the proteins. In this study, LC-MS/MS was used to profile whole beer, and two beer fractions representing hydrolysed hordeins (<30 kDa) and hordein peptide fragments (<10 kDa). Subsequently, multiple reaction monitoring (MRM) MS enabled the relative quantification of selected peptide fragments in beer and revealed that certain classes of hordein were prone to hydrolysis (B- and D-hordein). Furthermore, select beers contained very high levels of gluten-derived fragments. Strikingly, those beers that contained high levels of B-hordein fragments gave near zero values by ELISA. The hydrolysed fragments that persist in beer show a dose-dependent suppression of ELISA measurement of gluten despite using a hordein standard for calibration of the assay. The development of MS-based methodology for absolute quantification of gluten is required for the accurate assessment of gluten, including hydrolysed forms, in food and beverages to support the industry, legislation and to protect consumers suffering from CD. PMID:25454134

  3. A meningomyelocele with normal intracranial signs on ultrasound and false-negative amniotic fluid alpha-fetoprotein and acetylcholinesterase

    PubMed Central

    Yoon, Chong Hyeok; Kang, Sang Kyu; Jin, Chan Hee; Park, Moon Sun

    2014-01-01

    Neural tube defects are the major targets of prenatal diagnoses, along with Down syndrome. Prenatal diagnosis of spina bifida is possible at second trimester of gestation through ?-fetoprotein and acetylcholinesterase biochemistry assays and ultrasound. In particular, the discovery of characteristic intracranial signs on ultrasound leads to a very high diagnosis rate. However, it is rare for spina bifida to present without intracranial signs while also showing normal values of maternal serum ?-fetoprotein, amniotic fluid ?-fetoprotein, and acetylcholinesterase. In our hospital, a fetus with spina bifida was delivered at 37+5 weeks' gestation by cesarean section, and was continually followed up over 2 years to date. PMID:24883294

  4. A meningomyelocele with normal intracranial signs on ultrasound and false-negative amniotic fluid alpha-fetoprotein and acetylcholinesterase.

    PubMed

    Yoon, Chong Hyeok; Kang, Sang Kyu; Jin, Chan Hee; Park, Moon Sun; Rho, Jeong Hoon

    2014-05-01

    Neural tube defects are the major targets of prenatal diagnoses, along with Down syndrome. Prenatal diagnosis of spina bifida is possible at second trimester of gestation through ?-fetoprotein and acetylcholinesterase biochemistry assays and ultrasound. In particular, the discovery of characteristic intracranial signs on ultrasound leads to a very high diagnosis rate. However, it is rare for spina bifida to present without intracranial signs while also showing normal values of maternal serum ?-fetoprotein, amniotic fluid ?-fetoprotein, and acetylcholinesterase. In our hospital, a fetus with spina bifida was delivered at 37+5 weeks' gestation by cesarean section, and was continually followed up over 2 years to date. PMID:24883294

  5. To What Extent Could We Detect Field Defects? An Empirical Study of False Negatives in Static Bug Finding Tools

    E-print Network

    Devanbu, Prem

    Finding Tools Ferdian Thung1 , Lucia1 , David Lo1 , Lingxiao Jiang1 , Foyzur Rahman2 , and Premkumar T. Devanbu2 , 1 Singapore Management University, Singapore 2 University of California, Davis {ferdianthung,lucia

  6. Negative tandem mirror

    SciTech Connect

    Poulsen, P.; Allen, S.L.; Casper, T.A.; Grubb, D.P.; Jong, R.A.; Nexsen, W.E.; Porter, G.D.; Simonen, T.C.

    1981-11-30

    A tandem mirror configuration can be created by combining hot electron end cell plasmas with neutral beam pumping. A region of large negative potential formed in each end cell confines electrons in the central cell. The requirement of charge neutrality causes the central cell potential to become negative with respect to ground in order to confine ions as well as electrons. We discuss the method of producing and calculating the desired axial potential profile, and show the calculated axial potential profile and plasma parameters for a negative configuration of TMX-Upgrade.

  7. Kriging without negative weights

    SciTech Connect

    Szidarovszky, F.; Baafi, E.Y.; Kim, Y.C.

    1987-08-01

    Under a constant drift, the linear kriging estimator is considered as a weighted average of n available sample values. Kriging weights are determined such that the estimator is unbiased and optimal. To meet these requirements, negative kriging weights are sometimes found. Use of negative weights can produce negative block grades, which makes no practical sense. In some applications, all kriging weights may be required to be nonnegative. In this paper, a derivation of a set of nonlinear equations with the nonnegative constraint is presented. A numerical algorithm also is developed for the solution of the new set of kriging equations.

  8. Fate of False Vacuum in Superconducting Flux Qubits

    E-print Network

    Ali Izadi Rad; Hesam Zandi; Mehdi Fardmanesh

    2014-11-26

    We propose a similarity between the scenario of fate of false vacuum in cosmology at early universe and the situation in where the quantum state decays in superconducting Flux qubit. This is due to the fact that both cases have two homogeneous stable equilibrium states in scalar field, which in quantum theory, could penetrate through the barrier in different possibilities and hence considered unstable decaying in time. In quantum computation, decay rate is among the most important factors in characteristics of the system like coherency, reliability, measurement fidelity, etc. In this considered potential, the decay rate from the penetrating (False vacuum) state to the stable (absolute minimum) state is achieved to leading order in Planck constant by the approach of Instanton model. In case of the superconducting flux qubit having thin barrier potential, the decay rate is calculated and its relations with actual set of parameters in flux qubit design are introduced.

  9. CDF b-tagging: Measuring efficiency and false positive rate

    SciTech Connect

    Neu, Christopher; /Pennsylvania U.

    2006-06-01

    The CDF experiment has developed several high p{sub T} b-jet identification tools for the Run II physics program at the Tevatron. Herein we describe in detail one such b-tagging tool that exploits the long- lifetime of the b quark by identifying decay vertices significantly displaced from the primary interaction point. The b-tag efficiency is extracted from a b enriched data sample; the method is described, including a discussion of the important systematic effects. The data-driven measurement of the false positive tag rate is also described, as well as an explanation of how the per-jet false positive rate is used to predict the background contribution to the selected sample. Finally we conclude with a discussion of issues that have proven critical for b-tagging at CDF and should be given attention as we prepare b-tagging tools for LHC experiments.

  10. A textural approach for mass false positive reduction in mammography.

    PubMed

    Lladó, X; Oliver, A; Freixenet, J; Martí, R; Martí, J

    2009-09-01

    During the last decade several algorithms have been proposed for automatic mass detection in mammographic images. However, almost all these methods suffer from a high number of false positives. In this paper we propose a new approach for tackling this false positive reduction problem. The key point of our proposal is the use of Local Binary Patterns (LBP) for representing the textural properties of the masses. We extend the basic LBP histogram descriptor into a spatially enhanced histogram which encodes both the local region appearance and the spatial structure of the masses. Support Vector Machines (SVM) are then used for classifying the true masses from the ones being actually normal parenchyma. Our approach is evaluated using 1792 ROIs extracted from the DDSM database. The experiments show that LBP are effective and efficient descriptors for mammographic masses. Moreover, the comparison with current methods illustrates that our proposal obtains a better performance. PMID:19406614

  11. Modality effect in false recognition: evidence from Chinese characters.

    PubMed

    Mao, Wei Bin; Yang, Zhi Liang; Wang, Lin Song

    2010-02-01

    Using the Deese/Roediger-McDermott (DRM) false memory method, Smith and Hunt ( 1998 ) first reported the modality effect on false memory and showed that false recall from DRM lists was lower following visual study than following auditory study, which led to numerous studies on the mechanism of modality effect on false memory and provided many competing explanations. In the present experiment, the authors tested the modality effect in false recognition by using a blocked presentation condition and a random presentation condition. The present experiment found a modality effect different from the results of the previous research; namely, false recognition was shown to be greater following visual study than following auditory study, especially in the blocked presentation condition rather than in the random presentation condition. The authors argued that this reversed modality effect may be due to different encoding and processing characteristics between Chinese characters and English words. Compared with English words, visual graphemes of critical lures in Chinese lists are likely to be activated and encoded in participants' minds, thus it is more difficult for participants to discriminate later inner graphemes from those items presented in visual modality. Hence visual presentation could lead to more false recognition than auditory presentation in Chinese lists. The results in the present experiment demonstrated that semantic activation occurring during the encoding and retrieve phases played an important role in modality effect in false recognition, and our findings might be explained by the activation-monitoring account. Utilisant la méthode de fausse mémoire de Deese/Roediger-McDermott (DRM), Smith et Hunt ( 1998 ) ont d'abord rendu compte de l'effet de modalité sur la fausse mémoire et ils ont montré que le faux rappel à partir des listes de DRM était plus faible suivant une étude visuelle plutôt qu'une étude auditive. Ceci a mené à plusieurs études sur le mécanisme de l'effet de modalité sur la fausse mémoire, lesquelles ont fourni plusieurs explications concurrentes. Dans la présente expérience, les auteurs ont testé l'effet de modalité dans la fausse reconnaissance en utilisant une condition de présentation fixe et une condition de présentation aléatoire. Cette expérience a révélé un effet de modalité différent des résultats obtenus dans les recherches antérieures. En effet, la fausse reconnaissance était plus élevée suivant une étude visuelle plutôt qu'une étude auditive, spécialement dans la condition de présentation fixe. Les auteurs suggèrent que cet effet de modalité inverse peut être dû à des caractéristiques d'encodage et de processus différentes entre les caractères chinois et les mots anglais. Comparativement aux mots anglais, les graphèmes visuels des leurres critiques dans les listes chinoises sont susceptibles d'être activés et encodés dans l'esprit des participants, rendant plus difficile de discriminer les graphèmes intériorisés plus tard de ces items présentés dans la modalité visuelle. Ainsi, la présentation visuelle pourrait mener à davantage de fausse reconnaissance que la présentation auditive dans les listes chinoises. Les résultats de la présente expérience ont démontré que l'activation sémantique se produisait durant l'encodage et que la phase de retrait jouait un rôle important dans l'effet de modalité dans la fausse reconnaissance. Nos résultats peuvent être expliqués par la théorie activation-contrôle. Utilizando el método de Deese/Roediger-McDermott (DRM) de falsa mamoria, Smith y Hunt ( 1998 ) fueron los primeros en encontrar el efecto de modalidad en la falsa memoria y demostraron que los falsos recuerdos del listado DRM fueron más bajos después de un estudio visual que después de un estudio auditivo lo cual llevó a varios estudios sobre el mecanismo del efecto de la modalidad sobre falsos recuerdos y proporcionó varias explicaciones que compiten entre sí. En el presente trabajo, los autores estudiaron el efect

  12. ASSESSING THE SIGNIFICANCE OF APPARENT CORRELATIONS BETWEEN RADIO AND GAMMA-RAY BLAZAR FLUXES

    SciTech Connect

    Pavlidou, V.; Richards, J. L.; Max-Moerbeck, W.; King, O. G.; Pearson, T. J.; Readhead, A. C. S.; Reeves, R.; Stevenson, M. A. [California Institute of Technology, Owens Valley Radio Observatory, Pasadena, CA 91125 (United States); Angelakis, E.; Fuhrmann, L.; Zensus, J. A. [Max-Planck-Institut fuer Radioastronomie, Bonn 53121 (Germany); Giroletti, M. [INAF Istituto di Radioastronomia, Bologna (Italy); Reimer, A. [Institut fuer Astro- und Teilchenphysik and Institut fuer Theoretische Physik, Leopold-Franzes-Universitaet Innsbruck, Innsbruck,Austria (Austria); Healey, S. E.; Romani, R. W.; Shaw, M. S. [Department of Physics/KIPAC, Stanford University, Stanford, CA 94305 (United States)

    2012-06-01

    Whether or not a correlation exists between the radio and gamma-ray flux densities of blazars is a long-standing question, and one that is difficult to answer confidently because of various observational biases, which may either dilute or apparently enhance any intrinsic correlation between radio and gamma-ray luminosities. We introduce a novel method of data randomization to evaluate quantitatively the effect of these biases and to assess the intrinsic significance of an apparent correlation between radio and gamma-ray flux densities of blazars. The novelty of the method lies in a combination of data randomization in luminosity space (to ensure that the randomized data are intrinsically, and not just apparently, uncorrelated) and significance assessment in flux space (to explicitly avoid Malmquist bias and automatically account for the limited dynamical range in both frequencies). The method is applicable even to small samples that are not selected with strict statistical criteria. For larger samples we describe a variation of the method in which the sample is split in redshift bins, and the randomization is applied in each bin individually; this variation is designed to yield the equivalent to luminosity-function sampling of the underlying population in the limit of very large, statistically complete samples. We show that for a smaller number of redshift bins, the method yields a worse significance, and in this way it is conservative: although it may fail to confirm an existing intrinsic correlation in a small sample that cannot be split into many redshift bins, it will not assign a stronger, artificially enhanced significance. We demonstrate how our test performs as a function of number of sources, strength of correlation, and number of redshift bins used, and we show that while our test is robust against common-distance biases and associated false positives for uncorrelated data, it retains the power of other methods in rejecting the null hypothesis of no correlation for correlated data.

  13. Nursing behavior in captive false killer whales (Pseudorca crassidens)

    Microsoft Academic Search

    Steven T. Clark; Daniel K. Odell

    The nursing behavior of two false killer whale (Pseudorca crassidens) calves born at SeaWorld Florida was observed continually during the first 13 weeks of life. Nursing parameters, including total nursing time (mins\\/week), time spent nursing (mins\\/hour), suckles\\/hour, bouts\\/hour, suckles\\/ bout, suckle duration (secs) and bout duration (secs), peaked during the first week of life then slowly diminished. Mean nursing amount

  14. False learning function of an acoustic signal classifier

    NASA Astrophysics Data System (ADS)

    Goncharov, A. N.

    2004-09-01

    In works on statistical pattern recognition that use learning and examination, results of the learning depend not only on the feature efficiencies, but also on the proportion between the capacity of the decision rule, length of the learning sample, and number of features. It is usually difficult to calculate the recognition errors, which connect these basic quantities for a particular classifier, while the calculations are approximate and do not clearly characterize the results obtained in the process of the study. The purpose of this work is to develop a simple, clear, and efficient technique for the experimental estimation of the expected classification errors of the recognition engine employed in learning. The algorithm produces a sample of random noise segments, which is included in the recognition algorithm instead of the features of real signals. Portions of this uniform sample imitate different classes. The false learning function is produced as a result of a successive increase in the number of random features used in the recognition. The corresponding growth of the probability of recognizing artificial classes in such a false learning depends on the length of the learning sample and on the capacity of the decision rule employed. The main result of this work is the false learning function proposed for any particular classifier. The function is obtained for the same length of the learning sample as that of the one used to recognize real signals. The validity of results obtained in real signals can be estimated by comparing this function with experimental signal recognition probabilities with the same number of features. The simple false learning function is useful to characterize the validity of any experimental results on the statistical signal recognition in acoustics, seismoacoustics, and hydroacoustics; in speech recognition; in medical and industrial diagnostics; in radar; and in other fields.

  15. Brane nucleation as decay of the tachyon false vacuum

    SciTech Connect

    Cornalba, Lorenzo; Costa, Miguel S.; Penedones, Joao [Dip. di Fisica e Sez. INFN, Universita di Roma 'Tor Vergata', Rome (Italy); Centro de Fisica do Porto e Departamento de Fisica, Faculdade de Ciencias da Universidade do Porto (Portugal); Centro de Fisica do Porto e Departamento de Fisica, Faculdade de Ciencias da Universidade do Porto (Portugal)

    2005-08-15

    It is well known that spherical D-branes are nucleated in the presence of an external RR electric field. Using the description of D-branes as solitons of the tachyon field on non-BPS D-branes, we show that the brane nucleation process can be seen as the decay of the tachyon false vacuum. This process can describe the decay of flux-branes in string theory or the decay of quintessence potentials arising in flux compactifications.

  16. Children (but Not Adults) Can Inhibit False Memories

    Microsoft Academic Search

    Mark L. Howe

    2005-01-01

    The role of inhibition in children's (5-, 7-, and 11-year-olds') false memory illusions in the Deese- Roediger-McDermott (DRM) paradigm was examined using a list-wise directed-forgetting procedure. Children studiedeitherasingleDRMlist(control)ortwoDRMlistsin succession with a directed-remembering instruction or a directed-forgetting instruction between list presentations. The findings indicated that, like adults, children effectively suppressed the output of true memories when given a di- rected-forgetting instruction.

  17. False-vacuum decay in generalized extended inflation

    NASA Technical Reports Server (NTRS)

    Holman, Richard; Kolb, Edward W.; Vadas, Sharon L.; Wang, Yun

    1990-01-01

    False-vacuum decay was studied in context of generalized extended inflationary theories, and the bubble nucleation rates was computed for these theories in the limit of G(sub N) yields 0. It was found that the time dependence of the nucleation rate can be exponentially strong through the time dependence of the Jordan-Brans-Dicke field. This can have a pronounced effect on whether extended inflation can be successfully implemented.

  18. [False aneurysm on dacron prosthesis, 20 years after aortofemoral bypass].

    PubMed

    Illuminati, G; Bertagni, A; Nasti, A G; Montesano, G

    2001-10-01

    A 85-year-old male developed a false, non septic, non anastomotic aneurysm, 20 years after right aorto-femoral Dacron grafting for claudication. On account of the proximity to the femoral anastomosis, and the association with a profunda femoris stenosis, a conventional surgical repair was preferred to an endovascular treatment. The patient underwent a successful aneurysm resection followed by PTFE interposition between the primary graft and the profunda femoris artery, with uneventful recovery. PMID:11692765

  19. Phonological False Memories in Children and Adults: Evidence for a Developmental Reversal

    ERIC Educational Resources Information Center

    Swannell, Ellen R.; Dewhurst, Stephen A.

    2012-01-01

    False memories created by the Deese/Roediger-McDermott (DRM) procedure typically show a developmental reversal whereby levels of false recall increase with age. In contrast, false memories produced by phonological lists have been shown to decrease as age increases. In the current study we show that phonological false memories, like semantic false

  20. Individual Differences and False Confessions: A Conceptual Replication of Kassin and Kiechel (1996)

    Microsoft Academic Search

    Robert Horselenberg; Harald Merckelbach; Sarah Josephs

    2003-01-01

    In their study, Kassin and Kiechel (1996) falsely accused students of causing a computer crash and found that 69% of them were willing to sign a false confession, 28% internalized guilt, and 9% confabulated details to support their false beliefs. The authors interpreted these results to mean that false confessions can be easily elicited. However, in their study, false confessions

  1. Role of surface in apparent viscosity of glasses.

    PubMed

    Avramov, I

    2014-03-01

    Two problems have intrigued experts for a long time: The one is within the context of the legend of flowing cathedral glass windows and the second is the inaccuracy appearing in very old thermometers of famous scientists. We relate this with the role of the surface on the apparent viscosity of glasses. The apparent viscosity could deviate from the bulk viscosity if the fraction w of the surface molecules, of small samples, is sufficiently large. The effect is more prominent at low temperatures, correspondingly at high viscosities. The interpretation is within the Avramov and Milchev viscosity model, combined with the predictions of the change of heat capacity for extremely small samples. We find that the apparent glass transition temperature could depend on the sample size, in agreement with experimental observations existing in the literature. In addition to glasses, the present results could be of importance for thin films and foams. PMID:24730836

  2. Testing a flexible method to reduce false monsoon onsets.

    PubMed

    Stiller-Reeve, Mathew Alexander; Spengler, Thomas; Chu, Pao-Shin

    2014-01-01

    To generate information about the monsoon onset and withdrawal we have to choose a monsoon definition and apply it to data. One problem that arises is that false monsoon onsets can hamper our analysis, which is often alleviated by smoothing the data in time or space. Another problem is that local communities or stakeholder groups may define the monsoon differently. We therefore aim to develop a technique that reduces false onsets for high-resolution gridded data, while also being flexible for different requirements that can be tailored to particular end-users. In this study, we explain how we developed our technique and demonstrate how it successfully reduces false onsets and withdrawals. The presented results yield improved information about the monsoon length and its interannual variability. Due to this improvement, we are able to extract information from higher resolution data sets. This implies that we can potentially get a more detailed picture of local climate variations that can be used in more local climate application projects such as community-based adaptations. PMID:25105900

  3. Sun-glint false alarm mitigation in a maritime scenario

    NASA Astrophysics Data System (ADS)

    Rossi, Alessandro; Riccobono, Aldo; Landini, Stefano

    2014-10-01

    Airborne hyperspectral imaging can be exploited to detect anomalous objects in the maritime scenario. Due to the objects high contrast with respect to the sea surface, detection can be easily accomplished by means of local anomaly detectors, such as the well-known Reed-Xiaoli (RX) algorithm. During the development of a real-time system for the detection of anomalous pixels, it has been noticed that the performance of detection is deeply affected by the presence of sun-glint. The reflection on the sea surface of the solar radiation produces a high density of alarms, that makes challenging the task of detecting the objects of interest. In this paper, it is introduced a strategy aimed at discriminating the sun-glint false alarms from the effective alarms related to targets of potential interest. False alarms due to glint are mitigated performing a local spatio-spectral analysis on each alarm furnished by the anomaly detector. The technique has been tested on hyperspectral images collected during a measurement campaign carried out near Pisa, Italy. The Selex ES SIMGA hyperspectral sensor was mounted on board of an airplane to collect high spectral resolution images in both the VNIR and SWIR spectral channels. Several experiments were carried out, setting up scenarios with small man-made objects deployed on the sea surface, so as to simulate search and rescue operations. The results have highlighted the effectiveness of the proposed solution in terms of mitigation of false alarms due to sun-glints on the maritime scenario.

  4. False positives to confusable objects predict medial temporal lobe atrophy.

    PubMed

    Kivisaari, Sasa L; Monsch, Andreas U; Taylor, Kirsten I

    2013-09-01

    Animal models agree that the perirhinal cortex plays a critical role in object recognition memory, but qualitative aspects of this mnemonic function are still debated. A recent model claims that the perirhinal cortex is required to recognize the novelty of confusable distractor stimuli, and that damage here results in an increased propensity to judge confusable novel objects as familiar (i.e., false positives). We tested this model in healthy participants and patients with varying degrees of perirhinal cortex damage, i.e., amnestic mild cognitive impairment and very early Alzheimer's disease (AD), with a recognition memory task with confusable and less confusable realistic object pictures, and from whom we acquired high-resolution anatomic MRI scans. Logistic mixed-model behavioral analyses revealed that both patient groups committed more false positives with confusable than less confusable distractors, whereas healthy participants performed comparably in both conditions. A voxel-based morphometry analysis demonstrated that this effect was associated with atrophy of the anteromedial temporal lobe, including the perirhinal cortex. These findings suggest that also the human perirhinal cortex recognizes the novelty of confusable objects, consistent with its border position between the hierarchical visual object processing and medial temporal lobe memory systems, and explains why AD patients exhibit a heightened propensity to commit false positive responses with inherently confusable stimuli. PMID:23609914

  5. [Clinical and experimental study on false lateralizing sign (author's transl)].

    PubMed

    Ishiyama, R

    1978-10-01

    Clinical study is based upon the results of 68 cases of infratentorial tumor which have been examined in the Dept. of Neurosurgery, Tokyo Jikeikae University Hospital during the year 1967--1977. False lateralizing signs (F.L.S.) were studied of 57 cases except 11 pontine tumors. The incidence of this peculiar signs was 19.2% in 57 cases of infratentorial tumors, including 31.5% in 19 cases of cerebellopontine angle tumors, and 23.8% in 21 cases of cerebellar hemisphere tumor. A number of hypotheses have been proposed in the literature with regard to false lateralizing sign. The author presented the idea that elevated counter pressure elicited at a distance from the tumor may play significant role in producing this peculiar signs. Then the author undertook three-dimensional experiment on counter pressure mechanism, in order to elucidate the idea in cooperation with Material section, Trial production No. 1, Nissan Motor Car. Co. Ltd. The result showed that high counter pressure was observed at the contralateral cerebellopontine angle than the ipsilateral one to the compression. This means that when a mass grows at the posterior fossa on one side, lower cranial nerves of the contralateral side are easily compressed by the counter pressure mechanism from purely physical point of view. Therefore, there is a fair chance for the manifestation of false lateralizing signs. PMID:724061

  6. Global parameter optimization for maximizing radioisotope detection probabilities at fixed false alarm rates

    NASA Astrophysics Data System (ADS)

    Portnoy, David; Feuerbach, Robert; Heimberg, Jennifer

    2011-10-01

    Today there is a tremendous amount of interest in systems that can detect radiological or nuclear threats. Many of these systems operate in extremely high throughput situations where delays caused by false alarms can have a significant negative impact. Thus, calculating the tradeoff between detection rates and false alarm rates is critical for their successful operation. Receiver operating characteristic (ROC) curves have long been used to depict this tradeoff. The methodology was first developed in the field of signal detection. In recent years it has been used increasingly in machine learning and data mining applications. It follows that this methodology could be applied to radiological/nuclear threat detection systems. However many of these systems do not fit into the classic principles of statistical detection theory because they tend to lack tractable likelihood functions and have many parameters, which, in general, do not have a one-to-one correspondence with the detection classes. This work proposes a strategy to overcome these problems by empirically finding parameter values that maximize the probability of detection for a selected number of probabilities of false alarm. To find these parameter values a statistical global optimization technique that seeks to estimate portions of a ROC curve is proposed. The optimization combines elements of simulated annealing with elements of genetic algorithms. Genetic algorithms were chosen because they can reduce the risk of getting stuck in local minima. However classic genetic algorithms operate on arrays of Booleans values or bit strings, so simulated annealing is employed to perform mutation in the genetic algorithm. The presented initial results were generated using an isotope identification algorithm developed at Johns Hopkins University Applied Physics Laboratory. The algorithm has 12 parameters: 4 real-valued and 8 Boolean. A simulated dataset was used for the optimization study; the "threat" set of spectra contained 540 SNM and industrial signatures, and the "benign" set of spectra contained 240 NORM and medical signatures. As compared to a random parameter search, the statistical optimization was able to able to find parameters that yield significantly higher probabilities of detection for all probabilities of false alarm from 0 to 0.1 (and equal to for probabilities of false alarm greater than 0.1), in a relatively small number of iterations. The number of iterations used, 1000, is also many fewer than would be required for a reasonable systematic search of the parameter space.

  7. Logo and Negative Numbers.

    ERIC Educational Resources Information Center

    Strawn, Candace A.

    1998-01-01

    Describes LOGO's turtle graphics capabilities based on a sixth-grade classroom's activities with negative numbers and Logo programming. A sidebar explains LOGO and offers suggestions to teachers for using LOGO effectively. (LRW)

  8. Apparent 2-D diffusivity in a ruffled cell membrane.

    PubMed

    King, Michael R

    2004-04-01

    Most biological cell membranes have a microtopology that increases their surface area, including a highly ruffled surface in the case of leukocytes. Thus, molecular membrane diffusivities as measured by fluorescence recovery after photobleaching or other methods are decreased when projected onto a plane. We use a two-dimensional crested cycloid as a parameterized surface to simulate the random-walk diffusion of a molecule within a ruffled membrane. The apparent 2-D diffusivity was then calculated when the ruffled membrane is projected onto a plane. It is shown that the apparent diffusivity decreases as a function of the membrane area, to the -1.4 power. PMID:15019499

  9. On apparent temperature in low-frequency Alfvenic turbulence

    SciTech Connect

    Nariyuki, Yasuhiro [Faculty of Human Development, University of Toyama, 3190, Toyama City, Toyama 930-8555 (Japan)

    2012-08-15

    Low-frequency, parallel propagating Alfvenic turbulence in collisionless plasmas is theoretically studied. Alfvenic turbulence is derived as an equilibrium state (Beltrami field) in the magnetohydrodynamic equations with the pressure anisotropy and multi-species of ions. It is shown that the conservation of the total 'apparent temperature' corresponds to the Bernoulli law. A simple model of the radially expanding solar wind including Alfvenic turbulence is also discussed. The conversion of the wave energy in the 'apparent temperature' into the 'real temperature' is facilitated with increasing radial distance.

  10. Isotropic Single Negative Metamaterials

    Microsoft Academic Search

    Pavel PROTIVA; Michal BLÁHA; Ján ZEHENTNER

    This paper presents the application of simple, and therefore cheap, planar resonators for building 3D isotropic metamaterials. These resonators are: a broad- side-coupled split ring resonator with a magnetic response providing negative permeability; an electric dipole termi- nated by a loop inductor together with a double H-shaped resonator with an electric response providing negative permittivity. Two kinds of 3D isotropic

  11. Negative symptoms in schizophrenia.

    PubMed

    Boutros, Nash N; Mucci, Armida; Diwadkar, Vaibhav; Tandon, Rajiv

    2014-04-01

    Clinical heterogeneity is a confound common to all of schizophrenia research. Deficit schizophrenia has been proposed as a homogeneous disease entity within the schizophrenia syndrome. Utilizing the Schedule for the Deficit Syndrome (SDS) has allowed the definition of a subgroup dominated by persistent clusters of negative symptoms. While a number of studies have appeared over the years examining the electrophysiological correlates of the cluster of negative symptoms in schizophrenia, only a few studies have actually focused on the deficit syndrome (DS). PubMed as well as MEDLINE were searched for all reports indexed for "negative symptoms" or "deficit syndrome" and one of the following electrophysiology assessment tools: electroencephalography (EEG), evoked potentials (EPs), or polysomnography (PSG). While this line of research is evidently in its infancy, two significant trends emerge. First, spectral EEG studies link increased slow wave activity during wakefulness to the prevalence of negative symptoms. Secondly, sleep studies point to an association between decrease in slow wave sleep and prevalence of negative symptoms. Several studies also indicate a relationship of negative symptoms with reduced alpha activity. A host of other abnormalities--including sensory gating and P300 attenuation--are less consistently reported. Two studies specifically addressed electrophysiology of the DS. Both studies provided evidence suggesting that the DS may be a separate disease entity and not simply a severe form of schizophrenia. PMID:23428787

  12. A False Rejection Oriented Threat Model for the Design of Biometric Authentication Systems

    Microsoft Academic Search

    Ileana Buhan; Asker M. Bazen; Pieter H. Hartel; Raymond N. J. Veldhuis

    2006-01-01

    For applications like Terrorist Watch Lists and Smart Guns, a false rejection is more critical than a false acceptance. In this paper a new threat model focusing on false rejections is presented, and the \\

  13. 47 CFR 0.560 - Penalty for false representation of identity.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ...2010-10-01 false Penalty for false representation of identity. 0.560 Section 0.560 Telecommunication FEDERAL...Regulations § 0.560 Penalty for false representation of identity. Any individual who knowingly and willfully requests or...

  14. 47 CFR 0.560 - Penalty for false representation of identity.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ...2011-10-01 false Penalty for false representation of identity. 0.560 Section 0.560 Telecommunication FEDERAL...Regulations § 0.560 Penalty for false representation of identity. Any individual who knowingly and willfully requests or...

  15. 47 CFR 0.560 - Penalty for false representation of identity.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ...2012-10-01 false Penalty for false representation of identity. 0.560 Section 0.560 Telecommunication FEDERAL...Regulations § 0.560 Penalty for false representation of identity. Any individual who knowingly and willfully requests or...

  16. 47 CFR 0.560 - Penalty for false representation of identity.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ...2013-10-01 false Penalty for false representation of identity. 0.560 Section 0.560 Telecommunication FEDERAL...Regulations § 0.560 Penalty for false representation of identity. Any individual who knowingly and willfully requests or...

  17. 47 CFR 80.335 - Procedures for canceling false distress alerts.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... false Procedures for canceling false distress alerts. 80.335 Section 80.335 Telecommunication...335 Procedures for canceling false distress alerts. If a distress alert is inadvertently transmitted, the following...

  18. 47 CFR 80.335 - Procedures for canceling false distress alerts.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... false Procedures for canceling false distress alerts. 80.335 Section 80.335 Telecommunication...335 Procedures for canceling false distress alerts. If a distress alert is inadvertently transmitted, the following...

  19. 47 CFR 80.335 - Procedures for canceling false distress alerts.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... false Procedures for canceling false distress alerts. 80.335 Section 80.335 Telecommunication...335 Procedures for canceling false distress alerts. If a distress alert is inadvertently transmitted, the following...

  20. 47 CFR 80.335 - Procedures for canceling false distress alerts.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... false Procedures for canceling false distress alerts. 80.335 Section 80.335 Telecommunication...335 Procedures for canceling false distress alerts. If a distress alert is inadvertently transmitted, the following...

  1. Occurrence of False-Positive Most Probable Number Tests for Fecal Streptococci in Marine Waters1

    PubMed Central

    Buck, John D.

    1969-01-01

    By the use of the most probable number technique with azide dextrose and ethyl violet azide broths for enterococci, the common occurrence of false-positive tests was noted when marine and estuarine waters were sampled. Organisms isolated included a marine bacterium, gram-positive and gram-negative nonmarine bacteria, and yeasts. All cultures were capable of growth in azide-dextrose, ethyl violet-azide, and KF broths. Representative isolates grew in media containing 0.08% NaN3. The tentatively accepted most probable number method for fecal streptococci is thus of dubious value in assessment of sewage pollution levels in estuarine waters. All positive tubes must be examined microscopically for the presence of nonstreptococcal forms. PMID:4983956

  2. Prenatal Ultrasound Screening: False Positive Soft Markers May Alter Maternal Representations and Mother-Infant Interaction

    PubMed Central

    Viaux-Savelon, Sylvie; Dommergues, Marc; Rosenblum, Ouriel; Bodeau, Nicolas; Aidane, Elizabeth; Philippon, Odile; Mazet, Philippe; Vibert-Guigue, Claude; Vauthier-Brouzes, Danièle; Feldman, Ruth; Cohen, David

    2012-01-01

    Background In up to 5% of pregnancies, ultrasound screening detects a “soft marker” (SM) that places the foetus at risk for a severe abnormality. In most cases, prenatal diagnostic work-up rules out a severe defect. We aimed to study the effects of false positive SM on maternal emotional status, maternal representations of the infant, and mother-infant interaction. Methodology and Principal Findings Utilizing an extreme-case prospective case control design, we selected from a group of 244 women undergoing ultrasound, 19 pregnant women whose foetus had a positive SM screening and a reassuring diagnostic work up, and 19 controls without SM matched for age and education. In the third trimester of pregnancy, within one week after delivery, and 2 months postpartum, we assessed anxiety, depression, and maternal representations. Mother-infant interactions were videotaped during feeding within one week after delivery and again at 2 months postpartum and coded blindly using the Coding Interactive Behavior (CIB) scales. Anxiety and depression scores were significantly higher at all assessment points in the SM group. Maternal representations were also different between SM and control groups at all study time. Perturbations to early mother-infant interactions were observed in the SM group. These dyads showed greater dysregulation, lower maternal sensitivity, higher maternal intrusive behaviour and higher infant avoidance. Multivariate analysis showed that maternal representation and depression at third trimester predicted mother-infant interaction. Conclusion False positive ultrasound screenings for SM are not benign and negatively affect the developing maternal-infant attachment. Medical efforts should be directed to minimize as much as possible such false diagnoses, and to limit their psychological adverse consequences. PMID:22292077

  3. Apparent damage accumulation in cancellous bone using neural networks.

    PubMed

    Hambli, Ridha

    2011-08-01

    In this paper, a neural network model is developed to simulate the accumulation of apparent fatigue damage of 3D trabecular bone architecture at a given bone site during cyclic loading. The method is based on five steps: (i) performing suitable numerical experiments to simulate fatigue accumulation of a 3D micro-CT trabecular bone samples taken from proximal femur for different combinations of loading conditions; (ii) averaging the sample outputs in terms of apparent damage at whole specimen level based on local tissue damage; (iii) preparation of a proper set of corresponding input-output data to train the network to identify apparent damage evolution; (iv) training the neural network based on the results of step (iii); (v) application of the neural network as a tool to estimate rapidly the apparent damage evolution at a given bone site. The proposed NN model can be incorporated into finite element codes to perform fatigue damage simulation at continuum level including some morphological factors and some bone material properties. The proposed neural network based multiscale approach is the first model, to the author's knowledge, that incorporates both finite element analysis and neural network computation to rapidly simulate multilevel fatigue of bone. This is beneficial to develop enhanced finite element models to investigate the role of damage accumulation on bone damage repair during remodelling. PMID:21616468

  4. Apparent Temperature Dependence on Localized Atmospheric Water Vapor

    E-print Network

    Salvaggio, Carl

    the radiance reaching a thermal sensor from a target after passing through the water vapor plume. The DIRSIG and sensor. Water vapor absorption and emission dominates the 8 - 14 µm longwave infrared (LWIR) region [2Apparent Temperature Dependence on Localized Atmospheric Water Vapor Matthew Montanaroa, Carl

  5. INTRODUCTION Unlike Earth, Venus apparently lacks plate tectonics. Thus

    E-print Network

    Jurdy, Donna M.

    INTRODUCTION Unlike Earth, Venus apparently lacks plate tectonics. Thus plumes may be an important at different scales has been attributed to plume or diapiric activ- ity on Venus. Examples of these include activity in the Beta-Atla-Themis region, Venus Audeliz Matias Donna M. Jurdy* Department of Geological

  6. Apparent speed and speed sensitivity during adaptation to motion

    E-print Network

    Bex, Peter

    matching,4,8­12 and estimation of the time that it would take for a line to travel a particular distance.13, and the time constants of adaptation were much faster (5 s) than for recovery (22 s). Part of the loss to motion con- cerns a change in the apparent speed of a subsequently viewed moving pattern. This was first

  7. Thermodynamical Properties of Apparent Horizon in Warped DGP Braneworld

    E-print Network

    Ahmad Sheykhi; Bin Wang; Rong-Gen Cai

    2007-04-30

    In this paper we first obtain Friedmann equations for the $(n-1)$-dimensional brane embedded in the $(n+1)$-dimensional bulk, with intrinsic curvature term of the brane included in the action (DGP model). Then, we show that one can always rewrite the Friedmann equations in the form of the first law of thermodynamics, $dE=TdS+WdV$, at apparent horizon on the brane, regardless of whether there is the intrinsic curvature term on the brane or a cosmological constant in the bulk. Using the first law, we extract the entropy expression of the apparent horizon on the brane. We also show that in the case without the intrinsic curvature term, the entropy expressions are the same by using the apparent horizon on the brane and by using the bulk geometry. When the intrinsic curvature appears, the entropy of apparent horizon on the brane has two parts, one part follows the $n$-dimensional area formula on the brane, and the other part is the same as the entropy in the case without the intrinsic curvature term. As an interesting result, in the warped DGP model, the entropy expression in the bulk and on the brane are not the same. This is reasonable, since in this model gravity on the brane has two parts, one induced from the $(n+1)$-dimensional bulk gravity and the other due to the intrinsic curvature term on the brane.

  8. Apparent sizes of black holes and their alternatives

    Microsoft Academic Search

    James Graber

    2009-01-01

    Observers recently made a non-trivial measurement of the apparent diameter of Sagittarius A*, the black-hole candidate at the center of the Milky Way (Doeleman, et al., Nature, 4 September 2008). At face value, this measurement appears to be more than two sigma smaller than predicted. Better measurements are anticipated within the next five to 10 years, or perhaps much sooner.

  9. Apparent yield stress measurement in cemented paste backfill

    Microsoft Academic Search

    Dragana Simon; Murray Grabinsky

    2012-01-01

    The effect of specimen composition on the apparent yield stress of cemented paste backfill (CPB) is studied using a Brookfield rotational viscometer with vane geometry. The factors that are assessed include binder type and content, selected chemical admixtures (superplasticizers) and pore fluid chemistry (e.g. ionic concentration and pH). The difficulties associated with performing viscosity measurements on high solids content mixtures

  10. Apparent Hubble acceleration from large-scale electroweak domain structure

    E-print Network

    Tommy Anderberg

    2008-11-26

    The observed luminosity deficit of Type Ia supernovae (SNe Ia) at high redshift z can be explained by partial conversion to weak vector bosons of photons crossing large-scale electroweak domain boundaries, making Hubble acceleration only apparent and eliminating the need for a cosmological constant > 0.

  11. Discovery of an Apparent Nova in M81

    NASA Astrophysics Data System (ADS)

    Hornoch, K.; Alfaro, M. Diaz; Ordonez-Etxeberria, I.; Vaduvescu, O.

    2015-01-01

    We report the discovery of an apparent nova in M81 on a co-added 1600-s narrow-band H-alpha CCD image taken with the 2.5-m Isaac Newton Telescope (INT) + WFC at La Palma under ~2.4" seeing on 2015 Jan. 15.126 UT.

  12. Apparent digestible energy value of crude glycerol fed to pigs

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The apparent digestible energy of crude glycerol, a co-product of biodiesel production, was determined in two studies conducted at the Iowa State University Swine Nutrition Research Farm, Ames, IA. In the first study, 24 barrows with an average body weight of 11.0 kg were fed 376 g/d of a basal corn...

  13. Apparent mineralocorticoid excess: Type I and type II

    Microsoft Academic Search

    Franco Mantero; Mario Palermo; Massimiliano D. Petrelli; Rinaldo Tedde; Paul M. Stewart; Cedric H. L. Shackleton

    1996-01-01

    The syndrome of apparent mineralocorticoid excess (AME) is a heritable form of hypertension due to an inborn error of cortisol metabolism and is characterized by hypokalemia and low renin levels despite subnormal or normal levels of aldosterone and other known mineralocorticoids. The syndrome is attributable to congenital deficiency of the enzyme 11?-hydroxydehydrogenase (11?-HSD), which converts cortisol (F) to biologically inactive

  14. Explanation of the apparent sublinear photoconductivity of photorefractive barium titanate

    Microsoft Academic Search

    Daniel Mahgerefteh; Jack Feinberg

    1990-01-01

    We explain the apparent sublinear intensity dependence of photoconductivity in barium titanate. In our model shallow acceptors act as a reservoir for charges optically excited from the donors. As this reservoir fills, the fraction of occupied donors changes appreciably, changing the lifetime of the free carriers. We identify two types of barium titanate crystals having quite different photorefractive characteristics, depending

  15. Bias of apparent tracer ages in heterogeneous environments.

    PubMed

    McCallum, James L; Cook, Peter G; Simmons, Craig T; Werner, Adrian D

    2014-01-01

    The interpretation of apparent ages often assumes that a water sample is composed of a single age. In heterogeneous aquifers, apparent ages estimated with environmental tracer methods do not reflect mean water ages because of the mixing of waters from many flow paths with different ages. This is due to nonlinear variations in atmospheric concentrations of the tracer with time resulting in biases of mixed concentrations used to determine apparent ages. The bias of these methods is rarely reported and has not been systematically evaluated in heterogeneous settings. We simulate residence time distributions (RTDs) and environmental tracers CFCs, SF6 , (85) Kr, and (39) Ar in synthetic heterogeneous confined aquifers and compare apparent ages to mean ages. Heterogeneity was simulated as both K-field variance (?(2) ) and structure. We demonstrate that an increase in heterogeneity (increase in ?(2) or structure) results in an increase in the width of the RTD. In low heterogeneity cases, widths were generally on the order of 10 years and biases generally less than 10%. In high heterogeneity cases, widths can reach 100?s of years and biases can reach up to 100%. In cases where the temporal variations of atmospheric concentration of individual tracers vary, different patterns of bias are observed for the same mean age. We show that CFC-12 and CFC-113 ages may be used to correct for the mean age if analytical errors are small. PMID:23550995

  16. Apparent damage accumulation in cancellous bone using neural networks

    Microsoft Academic Search

    Ridha Hambli

    2011-01-01

    In this paper, a neural network model is developed to simulate the accumulation of apparent fatigue damage of 3D trabecular bone architecture at a given bone site during cyclic loading. The method is based on five steps: (i) performing suitable numerical experiments to simulate fatigue accumulation of a 3D micro-CT trabecular bone samples taken from proximal femur for different combinations

  17. False-positive results after environmental pinworm PCR testing due to Rhabditid nematodes in Corncob bedding.

    PubMed

    Leblanc, Mathias; Berry, Kristina; Graciano, Sandy; Becker, Brandon; Reuter, Jon D

    2014-11-01

    Modern rodent colonies are housed in individually ventilated cages to protect the animals from contamination with adventitious pathogens. Standard health monitoring through soiled-bedding sentinels does not always detect infections, especially in the context of low pathogen prevalence. Recently proposed alternatives include analyzing environmental samples from the cages or rack exhaust by PCR to improve the detection of rodent pathogens but optimal sampling strategies have not yet been established for different microorganisms. Although generally very sensitive and specific, these molecular assays are not foolproof and subject to false-positive and -negative results and should always be interpreted cautiously with an overall understanding of the intrinsic controls and all the variables that may affect the results. Here, we report a limited Aspiculuris tetraptera outbreak in a mouse barrier facility that was detected by fecal PCR in sentinels and confirmed by fecal flotation and direct cecal examination of both sentinels and colony animals. The outbreak led to a widespread survey of all facilities for pinworms by using environmental PCR from ventilated rack exhaust plenums. Environmental PCR suggested an unexpected widespread contamination of all ventilated racks holding nonautoclaved cages, but results could not be confirmed in sentinel or colony animals by fecal flotation, cecal and colonic examination, or cage PCR testing. After additional investigation, the unexpected environmental PCR results were confirmed as false-positive findings due to the nonspecificity of the assay, leading to the amplification of rhabditid nematodes, which are not infectious in rodents but which contaminated the corncob bedding. PMID:25650980

  18. Quantification of false positives within Moon Zoo crater annotations

    NASA Astrophysics Data System (ADS)

    Tar, P.; Thacker, N.

    2014-04-01

    The Moon Zoo citizen science project [1] allows members of the public to annotate lunar images, providing researchers with a wealth of location and size information regarding the population of small craters on the Moon. To date, approximately 4 million images have been inspected. Here, we show how a quantitative pattern recognition system can be used to estimate the quantity of contamination in Moon Zoo data from erroneous annotations. The proposed method produces not only estimates of true verses false crater annotations, but also a full error covariance, with additional conformity checks, which is essential for the meaningful interpretation of measurements, e.g. for plotting error bars.

  19. False Vacuum in the Supersymmetric Mass Varying Neutrinos Model

    E-print Network

    Ryo Takahashi; Morimitsu Tanimoto

    2007-11-04

    We present detailed analyses of the vacuum structure of the scalar potential in a supersymmetric Mass Varying Neutrinos model. The observed dark energy density is identified with false vacuum energy and the dark energy scale of order $(10^{-3}eV)^4$ is understood by gravitationally suppressed supersymmetry breaking scale, $F({TeV})^2/M_{Pl}$, in the model. The vacuum expectation values of sneutrinos should be tiny in order that the model works. Some decay processes of superparticles into acceleron and sterile neutrino are also discussed in the model.

  20. Mechanisms for Generating False Positives for Extrasolar Life

    NASA Astrophysics Data System (ADS)

    Domagal-Goldman, Shawn; Meadows, Victoria; Schwieterman, Edward; Luger, Rodrigo; Wordsworth, Robin; Barnes, Rory; Segura, Antigona; Claire, Mark; Virtual Planetary Laboratory

    2015-01-01

    Future mission concepts designed to look for life generally plan to search for oxygen (O2), ozone (O3), and/or methane (CH4). However, mechanisms exist for generating each of these species abiotically. In this presentation, we will review these processes, and discuss the atmospheres that result from them. In general, false positives can form in atmospheres with severe redox imbalance. This redox imbalance can also be thought of as extreme elemental composition, skewed towards very high or very low O/H ratios. Specific examples of this include: 1) loss of H through the top of a planetary atmosphere that leads to high O/H and an atmosphere rich in O2 and O3 2) atmospheres whose volcanism is O-rich and H-poor (i.e., highly oxidized), which leads to an atmosphere that with high O/H that can accumulate O3 and potentially O2 3) atmospheres in which H escape is slow, leading to low O/H and accumulation of CH4 and 4) atmospheres in which volcanic outgassing is H-rich (highly reduced), leading to low O/H and potential accumulation of CH4. Each of these cases would constitute a 'false positive' for life if O2, O3, or CH4 were detected without obtaining the chemical atmospheric context that could indicate a severe redox imbalance exists.Methods exist for discriminating between these 'false positives' where the gases arise from abiotic sources, and 'true positives' where the gases arise by biological sources. The best means of doing this is to obtain measurements of both O-rich (O2/O3) and H-rich (CH4) species, allowing identification of non-extreme O/H ratios in the atmosphere, and eliminating this abiotic source of O2, O3, and CH4. Because this is the most likely cause of abiotic production of these species, the elimination of this explanation would indicate that these gases were instead likely produced by biology.More specific methods to identify each of these false positives mechanisms also exist, but will not be discussed in detail in this presentation.

  1. Poisoning due to ingestion of Veratrum viride (false hellebore).

    PubMed

    Jaffe, A M; Gephardt, D; Courtemanche, L

    1990-01-01

    We present six cases of poisoning due to ingestion of Veratrum viride (false hellebore) and review the physiology of veratrum alkaloids. Significant bradycardia and hypotension can occur after intoxication by veratrum plants, which grow widely in swampy areas of the eastern and western United States. Nausea and vomiting also occur typically after ingestion. Atropine is the mainstay of therapy, but pressors may be required to maintain blood pressure. Cases of veratrum poisoning have not been widely reported in the emergency medicine literature. PMID:2362117

  2. Shaped graded materials with an apparent negative thermal conductivity C. Z. Fan, Y. Gao, and J. P. Huanga

    E-print Network

    Huang, Ji-Ping

    online 24 June 2008 Based on a first-principles approach, we exploit a class of shaped graded materials to satisfy a sum rule. Such shaped graded materials can serve as good candidates for thermal rectification. © 2008 American Institute of Physics. DOI: 10.1063/1.2951600 First we briefly review the recent

  3. Close Encounters of Two Kinds: False Alarms and Dashed Hopes

    Microsoft Academic Search

    Akshay R. Rao

    2002-01-01

    People are frequently exposed to potentially attractive events that are subsequently and unexpectedly reversed and to potentially painful events, which are also unexpectedly reversed. In the process of being returned to the initial asset position, does the sequence in which the positive and negative events occur matter? This issue of the combined effect of pleasurable and painful stimuli has received

  4. The lossy one-helper conjecture is false

    Microsoft Academic Search

    Aaron B. Wagner; Benjamin G. Kelly; Y. Altug

    2009-01-01

    We describe a scheme for rate-distortion with distributed encoding in which the sources to be compressed contain a common component. We show that this scheme is optimal in some situations and that it strictly improves upon existing schemes, which do not make full use of common components. This resolves in the negative an open question regarding whether independent quantization followed

  5. False Memory for Trauma-Related DRM Lists in Adolescents and Adults with Histories of Child Sexual Abuse

    PubMed Central

    Goodman, Gail S.; Ogle, Christin M.; Block, Stephanie D.; Harris, LaTonya S.; Larson, Rakel P.; Augusti, Else-Marie; Cho, Young Il; Beber, Jonathan; Timmer, Susan; Urquiza, Anthony

    2014-01-01

    The purpose of the present research was to examine Deese-Roediger-McDermott (DRM) false memory for trauma-related and nontrauma-related lists in adolescents and adults with and without documented histories of child sexual abuse (CSA). Individual differences in psychopathology and adult attachment were also explored. Participants were administered free recall and recognition tests after hearing CSA, negative, neutral, and positive DRM lists. In free recall, CSA and negative lists produced the most false memory. In sharp contrast, for recognition, CSA lists enjoyed the highest d’ scores. CSA-group adolescents who evinced greater PTSD symptoms had higher rates of false memory compared to: 1) nonCSA-group adolescents with higher PTSD symptom scores (free recall), and 2) CSA-group adolescents with lower PTSD symptom scores (recognition). Regression analyses revealed that individuals with higher PTSD scores and greater fearful-avoidant attachment tendencies showed less proficient memory monitoring for CSA lists. Implications for trauma and memory development and for translational research are discussed. PMID:23786687

  6. THE XO PLANETARY SURVEY PROJECT: ASTROPHYSICAL FALSE POSITIVES

    SciTech Connect

    Poleski, Radosaw [Astronomical Observatory, University of Warsaw, Al. Ujazdowskie 4, 00-478 Warszawa (Poland); McCullough, Peter R.; Valenti, Jeff A.; Burke, Christopher J.; Machalek, Pavel [Space Telescope Science Institute, 3700 San Martin Drive, Baltimore, MD 21218 (United States); Janes, Kenneth, E-mail: rpoleski@astrouw.edu.p [Astronomy Department, Boston University, 725 Commonwealth Avenue, Boston, MA 02215 (United States)

    2010-07-15

    Searches for planetary transits find many astrophysical false positives as a by-product. There are four main types analyzed in the literature: a grazing-incidence eclipsing binary (EB) star, an EB star with a small radius companion star, a blend of one or more stars with an unrelated EB star, and a physical triple star system. We present a list of 69 astrophysical false positives that had been identified as candidates of transiting planets of the on-going XO survey. This list may be useful in order to avoid redundant observation and characterization of these particular candidates that have been independently identified by other wide-field searches for transiting planets. The list may be useful for those modeling the yield of the XO survey and surveys similar to it. Subsequent observations of some of the listed stars may improve mass-radius relations, especially for low-mass stars. From the candidates exhibiting eclipses, we report three new spectroscopic double-line binaries and give mass function estimations for 15 single-line spectroscopic binaries.

  7. View of 'Cape St. Mary' from 'Cape Verde' (False Color)

    NASA Technical Reports Server (NTRS)

    2006-01-01

    As part of its investigation of 'Victoria Crater,' NASA's Mars Exploration Rover Opportunity examined a promontory called 'Cape St. Mary' from the from the vantage point of 'Cape Verde,' the next promontory counterclockwise around the crater's deeply scalloped rim. This view of Cape St. Mary combines several exposures taken by the rover's panoramic camera into a false-color mosaic. Contrast has been adjusted to improve the visibility of details in shaded areas.

    The upper portion of the crater wall contains a jumble of material tossed outward by the impact that excavated the crater. This vertical cross-section through the blanket of ejected material surrounding the crater was exposed by erosion that expanded the crater outward from its original diameter, according to scientists' interpretation of the observations. Below the jumbled material in the upper part of the wall are layers that survive relatively intact from before the crater-causing impact. Near the base of the Cape St. Mary cliff are layers with a pattern called 'crossbedding,' intersecting with each other at angles, rather than parallel to each other. Large-scale crossbedding can result from material being deposited as wind-blown dunes.

    The images combined into this mosaic were taken during the 970th Martian day, or sol, of Opportunity's Mars-surface mission (Oct. 16, 2006). The panoramic camera took them through the camera's 750-nanometer, 530-nanometer and 430-nanometer filters. The false color enhances subtle color differences among materials in the rocks and soils of the scene.

  8. False recollections and the congruence of suggested information.

    PubMed

    Pérez-Mata, Nieves; Diges, Margarita

    2007-10-01

    In two experiments, congruence of postevent information was manipulated in order to explore its role in the misinformation effect. Congruence of a detail was empirically defined as its compatibility (or match) with a concrete event. Based on this idea it was predicted that a congruent suggested detail would be more easily accepted than an incongruent one. In Experiments 1 and 2 two factors(congruence and truth value ) were manipulated within-subjects, and a two-alternative forced-choice recognition test was used followed by phenomenological judgements. Furthermore, in the second experiment participants were asked to describe four critical items (two seen and two suggested details)to explore differences and similarities between real and unreal memories. Both experiments clearly showed that the congruence of false information caused a robust misinformation effect, so that congruent information was much more accepted than false incongruent information. Furthermore, congruence increased the descriptive and phenomenological similarities between perceived and suggested memories, thus contributing to the misleading effect. PMID:17891682

  9. False positivity of gamma-glutamyl transpeptidase measurement in urine.

    PubMed

    Crivellenti, Leandro Zuccolotto; Mesa, Javier Sousa; Meirelles, Adriana Érica Wilkes Burton; Borin Crivellenti, Sofia; Mireya, Edna Gomes; Canola, Julio Carlos; Hatayde, Mário Roberto; Santana, Aureo Evangelista; Dantas, Márcio; Silva, Gyl Eanes Barros

    2014-05-01

    Although enzymuria tends to be associated to renal injury, there are no studies that have evaluated the presence of the enzyme gamma-glutamyl transpeptidase (GGT) spectrophotometry in the urine using a non-nephrotoxic agent (Nerium oleander) in order to evaluate the possibility of false positive results. The urinary GGT/urinary creatinine concentration ratio (uGGT/uCr) of 10 healthy dogs was calculated and posteriorly confronted with data from clinical evaluation, hematological and serum biochemical profiles, creatinine clearance (CrC), urinalysis, urine protein/creatinine ratio (UPC), electrocardiogram, systemic blood pressure (SBP) and light and electron microscopy. The results for kidney histology, SBP, UPC and CrC were not significantly different in any of the time-points analyzed. However, uGGT/uCr was significantly higher when measured 4 hours and 24 hours after administration of N. oleander. The measurement of the urinary GGT enzyme, as performed in many studies, yielded false positive results in dogs poisoned by a non-nephrotoxic agent. PMID:24456228

  10. Further Evidence for Nonspecificity of Theory of Mind in Preschoolers: Training and Transferability in the Understanding of False Beliefs and False Signs

    ERIC Educational Resources Information Center

    Iao, Lai-Sang; Leekam, Susan; Perner, Josef; McConachie, Helen

    2011-01-01

    In a training study, the authors addressed whether or not preschoolers' difficulty with false belief is due to a domain-specific problem with mental states. Following Slaughter's (1998) design, 57 children who failed a false-belief (FB) pretest received two sessions of training on either an FB, false sign (FS), or control task. All children were…

  11. The Role of the Counterfactually Satisfied Desire in the Lag between False-Belief and False-Emotion Attributions in Children Aged 4-7

    ERIC Educational Resources Information Center

    Bradmetz, Joel; Schneider, Roland

    2004-01-01

    A robust lag was evidenced between the attribution to an individual of a false belief about the world and the attribution of the false emotion associated with this false belief (Bradmetz & Schneider, 1999). This lag was unexpected in the frame of current theories of mind which consider that emotion has a rational cognitive basis. The present paper…

  12. False-positive reduction in CAD mass detection using a competitive classification strategy.

    PubMed

    Li, L; Zheng, Y; Zhang, L; Clark, R A

    2001-02-01

    High false-positive (FP) rate remains to be one of the major problems to be solved in CAD study because too many false-positively cued signals will potentially degrade the performance of detecting true-positive regions and increase the call-back rate in CAD environment. In this paper, we proposed a novel classification method for FP reduction, where the conventional "hard" decision classifier is cascaded with a "soft" decision classification with the objective to reduce false-positives in the cases with multiple FPs retained after the "hard" decision classification. The "soft" classification takes a competitive classification strategy in which only the "best" ones are selected from the pre-classified suspicious regions as the true mass in each case. A neural network structure is designed to implement the proposed competitive classification. Comparative studies of FP reduction on a database of 79 images by a "hard" decision classification and a combined "hard"-"soft" classification method demonstrated the efficiency of the proposed classification strategy. For example, for the high FP sub-database which has only 31.7% of total images but accounts for 63.5% of whole FPs generated in single "hard" classification, the FPs can be reduced for 56% (from 8.36 to 3.72 per image) by using the proposed method at the cost of 1% TP loss (from 69% to 68%) in whole database, while it can only be reduced for 27% (from 8.36 to 6.08 per image) by simply increasing the threshold of "hard" classifier with a cost of TP loss as high as 14% (from 69% to 55%). On the average in whole database, the FP reduction by hybrid "hard"-"soft" classification is 1.58 per image as compared to 1.11 by "hard" classification at the TP costs described above. Because the cases with high dense tissue are of higher risk of cancer incidence and false-negative detection in mammogram screening, and usually generate more FPs in CAD detection, the method proposed in this paper will be very helpful in improving the performance of early detection of breast cancer with CAD. PMID:11243350

  13. Negative regulation contributes to tissue specificity of the immunoglobulin heavy-chain enhancer.

    PubMed Central

    Imler, J L; Lemaire, C; Wasylyk, C; Wasylyk, B

    1987-01-01

    We have identified in and around the immunoglobulin heavy-chain enhancer two apparently distinct negative regulatory elements which repress immunoglobulin H enhancer, simian virus 40 enhancer, and heterologous promoter activity in fibroblasts but not in myeloma cells. We propose that in nonlymphoid cells, negative regulatory elements prevent activation of the immunoglobulin H enhancer by ubiquitous stimulatory trans-acting factors. Images PMID:3039350

  14. 45 CFR 73.735-904 - Resolution of apparent or actual conflicts of interest.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ...Resolution of apparent or actual conflicts of interest. 73.735-904 Section...Resolution of apparent or actual conflicts of interest. (a) Disqualification...resolving apparent or actual conflicts of interest when the interest or...

  15. Realistic artificial DNA sequences as negative controls for computational genomics

    PubMed Central

    Caballero, Juan; Smit, Arian F. A.; Hood, Leroy; Glusman, Gustavo

    2014-01-01

    A common practice in computational genomic analysis is to use a set of ‘background’ sequences as negative controls for evaluating the false-positive rates of prediction tools, such as gene identification programs and algorithms for detection of cis-regulatory elements. Such ‘background’ sequences are generally taken from regions of the genome presumed to be intergenic, or generated synthetically by ‘shuffling’ real sequences. This last method can lead to underestimation of false-positive rates. We developed a new method for generating artificial sequences that are modeled after real intergenic sequences in terms of composition, complexity and interspersed repeat content. These artificial sequences can serve as an inexhaustible source of high-quality negative controls. We used artificial sequences to evaluate the false-positive rates of a set of programs for detecting interspersed repeats, ab initio prediction of coding genes, transcribed regions and non-coding genes. We found that RepeatMasker is more accurate than PClouds, Augustus has the lowest false-positive rate of the coding gene prediction programs tested, and Infernal has a low false-positive rate for non-coding gene detection. A web service, source code and the models for human and many other species are freely available at http://repeatmasker.org/garlic/. PMID:24803667

  16. Realistic artificial DNA sequences as negative controls for computational genomics.

    PubMed

    Caballero, Juan; Smit, Arian F A; Hood, Leroy; Glusman, Gustavo

    2014-07-01

    A common practice in computational genomic analysis is to use a set of 'background' sequences as negative controls for evaluating the false-positive rates of prediction tools, such as gene identification programs and algorithms for detection of cis-regulatory elements. Such 'background' sequences are generally taken from regions of the genome presumed to be intergenic, or generated synthetically by 'shuffling' real sequences. This last method can lead to underestimation of false-positive rates. We developed a new method for generating artificial sequences that are modeled after real intergenic sequences in terms of composition, complexity and interspersed repeat content. These artificial sequences can serve as an inexhaustible source of high-quality negative controls. We used artificial sequences to evaluate the false-positive rates of a set of programs for detecting interspersed repeats, ab initio prediction of coding genes, transcribed regions and non-coding genes. We found that RepeatMasker is more accurate than PClouds, Augustus has the lowest false-positive rate of the coding gene prediction programs tested, and Infernal has a low false-positive rate for non-coding gene detection. A web service, source code and the models for human and many other species are freely available at http://repeatmasker.org/garlic/. PMID:24803667

  17. Volumetric single negative metamaterials

    Microsoft Academic Search

    J. Zehentner; J. Machac

    This paper presents the results of a study of bulk single negative isotropic metamaterials. Magnetic and electric metamaterials are treated separately. The same approach was used for developing anisotropic particles with magnetic or electric responses. A volumetric isotropic medium was made up consecutively from unit cells with cubic symmetry of the particles, and in parallel by random or quasi-periodic location

  18. Negative Binomial Experiment

    NSDL National Science Digital Library

    Kyle Siegrist

    This resource consists of a Java applet and descriptive text. The applet illustrates the number of trials needed to get a specified number of successes in Bernoulli trials, in terms of random points on a discrete timeline. The applet illustrates the negative binomial distribution. The number of successes and the probability of success can be varied.

  19. Optically induced 'negative forces'

    NASA Astrophysics Data System (ADS)

    Dogariu, Aristide; Sukhov, Sergey; Sáenz, José

    2013-01-01

    Attracting objects with optical beams may seem like science fiction, but various schemes already do this, albeit with some caveats and limitations. The most recent progress in this emerging field is reviewed, with particular emphasis on manipulation of small objects by optically induced 'negative forces'.

  20. Inventing Negative Numbers

    NSDL National Science Digital Library

    2008-10-10

    In this quick time video segment from Cyberchase, viewers learn about extending a vertical number line below zero as they watch the CyberSquad rescue the Cyberspace Council, which is being held captive by Hacker in a tall building. This video is also featured in the lesson plan: "Introducing Negative Numbers" (cataloged separately). Teaching Tips and a transcript are included.

  1. The apparent torsional barrier reduction effect in methanol complexes

    SciTech Connect

    Tan, Xue Qing; Sun, Linghong; Kuczkowski, R.L. [Univ. of Michigan, Ann Arbor, MI (United States)

    1995-12-31

    Rotational analyses of several methanol complexes have indicated that the methyl group torsional barrier heights in these complexes are substantially lower than in bare methanol. It was proposed recently that this barrier reduction effect is only apparent. It results from neglect of the large amplitude {open_quotes}librational{close_quotes} motion of the hydroxyl hydrogen in methanol. Fraser et al. proposed a simple Hamiltonian to analize this effect, where v{sub 1} is the potential barrier that hinders the hydroxyl group internal rotation (or wagging). Data taken for CH{sub 3}OH{center_dot}Ar, CH{sub 3}OH{center_dot}SO{sub 2}, and CH{sub 3}OH{center_dot}HCl will be presented to illustrate the barrier reduction effect. Isotopic variation of the apparent barrier height will be used to check the validity of the model. The physical significance of v{sub i} in these complexes will be discussed.

  2. The Apparent Velocity and Acceleration of Relativistically Moving Objects

    E-print Network

    Austen Berlet; Dennis G. C. McKeon; Farrukh Chishtie; Martin Houde

    2011-02-22

    Although special relativity limits the actual velocity of a particle to $c$, the velocity of light, the observed velocity need not be the same as the actual velocity as the observer is only aware of the position of a particle at the time in the past when it emits the detected signal. We consider the apparent speed and acceleration of a particle in two cases, one when the particle is moving with a constant speed and the other when it is moving with a constant acceleration. One curious feature of our results is that in both cases, if the actual velocity of the particle approaches $c$, then the apparent velocity approaches infinity when it is moving toward the observer and $c/2$ when it is moving away from the observer.

  3. Wavelength dependence of the apparent diameter of retinal blood vessels

    NASA Astrophysics Data System (ADS)

    Park, Robert; Twietmeyer, Karen; Chipman, Russell; Beaudry, Neil; Salyer, David

    2005-04-01

    Imaging of retinal blood vessels may assist in the diagnosis and monitoring of diseases such as glaucoma, diabetic retinopathy, and hypertension. However, close examination reveals that the contrast and apparent diameter of vessels are dependent on the wavelength of the illuminating light. In this study multispectral images of large arteries and veins within enucleated swine eyes are obtained with a modified fundus camera by use of intravitreal illumination. The diameters of selected vessels are measured as a function of wavelength by cross-sectional analysis. A fixed scale with spectrally independent dimension is placed above the retina to isolate the chromatic effects of the imaging system and eye. Significant apparent differences between arterial and venous diameters are found, with larger diameters observed at shorter wavelengths. These differences are due primarily to spectral absorption in the cylindrical blood column.

  4. Apparent prevalence of dourine in the Khomas region of Namibia.

    PubMed

    Kumba, F F; Claasen, B; Petrus, P

    2002-12-01

    A 15-year record of the results of horse sera from the Khomas region of Namibia tested by the complement fixation test for dourine at the Central Veterinary Laboratory in Windhoek before clearing the respective animals for export and competitive sport were subjected to statistical analysis. The range of percentage positive, taken as the apparent prevalence of dourine for the region, during the period of study, was 0-29.09%; the average regional level of apparent prevalence was 8.33%. These figures were thought to be lower than the real situation due to some bias in the sampling criteria. For more accurate results, the more reliable enzyme-linked immunosorbent assay techniques are recommended for use in sero-surveys for dourine in Khomas and other regions of Namibia to provide a basis for development of effective control strategies against the disease. PMID:12625381

  5. Defect-assisted apparent lowering of band offsets

    NASA Astrophysics Data System (ADS)

    Stievenard, D.; Letartre, X.; Lannoo, M.; Ababou, S.; Guillot, G.

    1994-04-01

    We present a study of the emission of electrons from a well into the conduction band of the associated barrier. The process involved is not the usual thermionic one but a defect-assisted tunneling process, occurring from the quantum states of the well to the energy levels of the conduction band of the associated barrier, and via the energy level associated with a defect located in the barrier. This tunneling process occurs because there is band bending of the conduction band associated with the charge located in the well. This mechanism results in an apparent lowering of the band offset, which is a function of the ionization energy ?0 associated with the defect. Evidence of this effect is obtained on a AlxIn1-xAs/GayIn1-yAs/AlxIn1-xAs quantum well. The apparent offset lowering is measured using the admittance spectroscopy technique and is consistent with theory.

  6. Police Officer Schema of Sexual Assault Reports: Real Rape, Ambiguous Cases, and False Reports.

    PubMed

    Venema, Rachel M

    2014-11-12

    While extensive research has studied sexual assault reporting behaviors and described negative experiences with the criminal justice system among victim-survivors, fewer studies have explored police officer attitudes, knowledge, and thought processes that may affect victims' perceptions of negative interactions and unsatisfactory outcomes within reported sexual assault cases. This study explores police officer understanding of the definition of sexual assault and characteristics that influence their perceptions and response. Ten police officers were interviewed within one police department in a midsized city in the Great Lakes region. The study uses a modified grounded theory approach. Findings suggest that officers employ distinct schema of reported sexual assaults. Case characteristics, perceived credibility of the victim, and types of evidence formed categorizations of false reports, ambiguous cases, and legitimate sexual assaults. Police officers describe the ways in which perceptions of the case may or may not influence the response and point to areas for improvement within police procedure. The study findings provide insight into recommendations for improved police interviewing and response to reported sexual assaults. PMID:25395222

  7. Judged displacement in apparent vertical and horizontal motion

    Microsoft Academic Search

    Timothy L. Hubbard; Jamshed J. Bharucha

    1988-01-01

    The judged vanishing point of a target traveling along a vertical or horizontal trajectory at uniform velocity was examined.\\u000a In Experiments 1 and 2, subjects indicated the vanishing point by positioning a cross hair. Judged vanishing point was displaced\\u000a forward in the direction of motion, and the magnitude of the displacement increased with the apparent velocity of the target.\\u000a Displacement

  8. Unagreement is an Illusion. Apparent person mismatches and nominal structure

    E-print Network

    Höhn, Georg F.K.

    2015-01-01

    and gender are expressed on both the subject and the verb, the relevant markings may not be contradictory. Interestingly, languages occasionally seem to violate this requirement (cf. e.g. Corbett 2006, ch. 5). One such apparent agreement mismatch has been... added and translation adapted. Unagreement is an Illusion 3 In this paper I will not be concerned with the gender-mismatch phenomena often observed for Slavic languages (e.g. Corbett 2006, 158). I also distinguish unagreement from Collins and Postal...

  9. Article de synthse Le peptide apparent l'hormone

    E-print Network

    Boyer, Edmond

    and kidney in a way similar to that of para- thyroid hormone. PTHrP released by fetal parathyroid glandsArticle de synthèse Le peptide apparenté à l'hormone parathyroïdienne (PTHrP) JP Barlet MJ Davicco rencontrée dans certaines formes de cancers humains et animaux, présente de nombreuses analogies avec l'hormone

  10. Apparent kinetics of high temperature oxidative decomposition of microalgal biomass.

    PubMed

    Ali, Saad Aldin M; Razzak, Shaikh A; Hossain, Mohammad M

    2014-10-28

    The oxidative thermal characteristics of two microalgae species biomass Nannochloropsis oculta and Chlorella vulgaris have been investigated. The apparent kinetic parameters for the microalgal biomass oxidation process are estimated by fitting the experimental data to the nth order rate model. Also, the iso-conversional methods Kissinger-Akahira-Sunose (KAS) and Flynn-Wall-Ozawa (FWO) were used to evaluate the apparent activation energy. The results indicate that biomass of different microalgae strains exhibit different thermal behavior and characteristics. In addition, growth parameters and medium composition can affect the biomass productivity and composition. This would have significant impact on the thermal decomposition trend of the biomass. The kinetic modeling of the oxidation reaction with direct model fitting method shows good prediction to the experimental data. The apparent activation energies estimated by KAS and FWO methods for N. oculta were 149.2 and 151.8kJ/mol, respectively, while for C. vulgaris were 214.4 and 213.4kJ/mol, respectively. PMID:25459869

  11. Corrections of surface fissure effect on apparent resistivity measurements

    NASA Astrophysics Data System (ADS)

    Gance, J.; Sailhac, P.; Malet, J.-P.

    2015-02-01

    Electrical resistivity tomography (ERT) is a useful tool to detect and track water flow paths in the subsoil. However, measurements are strongly affected by subsurface heterogeneities such as fissures of different sizes and genesis (shrinking-swelling, macropores and deformation). In this work, we focus on surface fissures characterized by dimensions lower than the interelectrode spacing and correct their effect on apparent resistivity pseudo-sections by incorporating fissure geometry in the topography. We show that fissures with depths greater than 0.10 times the interelectrode spacing for a dipole-dipole array and equal to 0.16 for the gradient array and the Wenner-Schlumberger arrays create significant anomalies (greater than 5 per cent) in the pseudo-section. Surface fissure widths and dip angles have little effect with respect to the fissure depths which can increase the apparent resistivity up to 200 per cent. The clogging of the fissures with water or soil material decreases the anomaly effect linearly with the percentage of filling. The correction of apparent resistivity values is possible for relatively simple fissure geometries and only requires a manual survey of the surface fissures. It allows to improve the quality of the inverted resistivity section by mitigating the inversion artefacts and therefore a better interpretation.

  12. Social sampling explains apparent biases in judgments of social environments.

    PubMed

    Galesic, Mirta; Olsson, Henrik; Rieskamp, Jörg

    2012-12-01

    How people assess their social environments plays a central role in how they evaluate their life circumstances. Using a large probabilistic national sample, we investigated how accurately people estimate characteristics of the general population. For most characteristics, people seemed to underestimate the quality of others' lives and showed apparent self-enhancement, but for some characteristics, they seemed to overestimate the quality of others' lives and showed apparent self-depreciation. In addition, people who were worse off appeared to enhance their social position more than those who were better off. We demonstrated that these effects can be explained by a simple social-sampling model. According to the model, people infer how others are doing by sampling from their own immediate social environments. Interplay of these sampling processes and the specific structure of social environments leads to the apparent biases. The model predicts the empirical results better than alternative accounts and highlights the importance of considering environmental structure when studying human cognition. PMID:23104680

  13. Diffuse sorption modeling: apparent H/Na, or the same, Al/Na exchange on clays.

    PubMed

    Pivovarov, Sergey

    2009-08-15

    Clay minerals are specified by permanent negative surface charge. In solutions of sodium salts, the surface of clay is covered by exchangeable sodium ions. In an acidic field (pH<4-6), sodium ions are displaced from the surface. This apparent H/Na exchange is conditioned by dissolution of alumina, followed by Al/Na exchange. Two kinds of published experimental data were considered in order to follow Al/Na exchange: the first is direct measurement of exchangeable sodium and aluminum in clay, and the second is exchange sorption of trace metal. Because of the equivalency of ionic exchange, trace metal acts as a probe, indicating the sodium content in clay. These experimental data were successfully modeled with use of the Poisson-Boltzmann equation, with the assumption that all exchange cations are located in the diffuse layer. PMID:19464695

  14. Six consecutive false positive cases from cell-free fetal DNA testing in a single referring centre

    PubMed Central

    Dugo, Nella; Padula, Francesco; Mobili, Luisa; Brizzi, Cristiana; D’Emidio, Laura; Cignini, Pietro; Mesoraca, Alvaro; Bizzoco, Domenico; Cima, Antonella; Giorlandino, Claudio

    2014-01-01

    Introduction recent studies have proposed the introduction of cell-free fetal DNA testing (NIPT-Non Invasive Prenatal Testing) in routine clinical practice emphasizing its high sensibility and specificity. In any case, false positive and false negative findings may result from placental mosaicism, because cell-free fetal DNA originates mainly from placenta. Case we report six cases of women who underwent chorionic villus sampling (CVS) or amniocentesis to confirm the results from NIPT: two Turner syndromes, two Triple X, one Patau syndrome, one Edward syndrome. Results using classic cytogenetic analysis and, also, Array - Comparative Genomic Hybridization (Array CGH) the karyotype of all 5 fetuses was found to be normal. Conclusion results from NIPT must always be confirmed by invasive prenatal diagnosis. It is mandatory to inform the patient that the CVS and amniocentesis still represent the only form of prenatal diagnostic test available. PMID:25332757

  15. False alarm recognition in hyperspectral gas plume identification

    DOEpatents

    Conger, James L. (San Ramon, CA); Lawson, Janice K. (Tracy, CA); Aimonetti, William D. (Livermore, CA)

    2011-03-29

    According to one embodiment, a method for analyzing hyperspectral data includes collecting first hyperspectral data of a scene using a hyperspectral imager during a no-gas period and analyzing the first hyperspectral data using one or more gas plume detection logics. The gas plume detection logic is executed using a low detection threshold, and detects each occurrence of an observed hyperspectral signature. The method also includes generating a histogram for all occurrences of each observed hyperspectral signature which is detected using the gas plume detection logic, and determining a probability of false alarm (PFA) for all occurrences of each observed hyperspectral signature based on the histogram. Possibly at some other time, the method includes collecting second hyperspectral data, and analyzing the second hyperspectral data using the one or more gas plume detection logics and the PFA to determine if any gas is present. Other systems and methods are also included.

  16. False-color composite image of Raco, Michigan

    NASA Technical Reports Server (NTRS)

    1994-01-01

    This image is a false color composite of Raco, Michigan, centered at 46.39 north latitude and 84.88 east longitude. This image was acquired by the Spaceborne Imaging Radar-C/X-band Synthetic Aperture Radar (SIR-C/X-SAR) on the 20th orbit of the Shuttle Endeavour. The area shown is approximately 20 kilometers by 50 kilometers. Raco is located at the eastern end of Michigan's upper peninsula, west of Sault Ste. Marie and south of Whitefish Bay on Lake Superior. In this color representation, darker areas in the image are smooth surfaces such as frozen lakes and other non-forested areas. The colors are related to the types of trees and the brightness is related to the amount of plant material covering the surface, called forest biomass. The Jet Propulsion Laboratory alternative photo number is P-43882.

  17. Rover's Wheel Churns Up Bright Martian Soil (False Color)

    NASA Technical Reports Server (NTRS)

    2009-01-01

    NASA's Mars Exploration Rover Spirit acquired this mosaic on the mission's 1,202nd Martian day, or sol (May 21, 2007), while investigating the area east of the elevated plateau known as 'Home Plate' in the 'Columbia Hills.' The mosaic shows an area of disturbed soil, nicknamed 'Gertrude Weise' by scientists, made by Spirit's stuck right front wheel.

    The trench exposed a patch of nearly pure silica, with the composition of opal. It could have come from either a hot-spring environment or an environment called a fumarole, in which acidic, volcanic steam rises through cracks. Either way, its formation involved water, and on Earth, both of these types of settings teem with microbial life.

    The image is presented here in false color that is used to bring out subtle differences in color.

  18. Daisy in Full Bloom on 'Mazatzal' (False Color)

    NASA Technical Reports Server (NTRS)

    2004-01-01

    This image from NASA's Mars Exploration Rover Spirit shows a daisy pattern created by the rover's rock abrasion tool on a rock dubbed 'Mazatzal.' The pattern was made as the rover brushed dust away from a large enough area of the surface of the wind-scalloped, volcanic rock to match the field of view of the rover's miniature thermal emission spectrometer. As Spirit ground into the surface with the diamond cutting teeth of the rock abrasion tool, a mineral-filled fracture in the rock suggested the possible presence of past water. The circles cut by the tool are about 5 centimeters (2 inches) in diameter.

    Spirit acquired this image on Sol 86 (March 31, 2004) with the panoramic camera's 753-nanometer, 535-nanometer, and 432-nanometer filters. The image is presented here in false color that is used to bring out subtle color differences.

  19. Apparent Survival Rates of Forest Birds in Eastern Ecuador Revisited: Improvement in Precision but No Change in Estimates

    PubMed Central

    Blake, John G.; Loiselle, Bette A.

    2013-01-01

    Knowledge of survival rates of Neotropical landbirds remains limited, with estimates of apparent survival available from relatively few sites and species. Previously, capture-mark-recapture models were used to estimate apparent survival of 31 species (30 passerines, 1 Trochilidae) from eastern Ecuador based on data collected from 2001 to 2006. Here, estimates are updated with data from 2001-2012 to determine how additional years of data affect estimates; estimates for six additional species are provided. Models assuming constant survival had highest support for 19 of 31 species when based on 12 years of data compared to 27 when based on six; models incorporating effects of transients had the highest support for 12 of 31 species compared to four when based on 12 and six years, respectively. Average apparent survival based on the most highly-supported model (based on model averaging, when appropriate) was 0.59 (± 0.02 SE) across 30 species of passerines when based on 12 years and 0.57 (± 0.02) when based on six. Standard errors of survival estimates based on 12 years were approximately half those based on six years. Of 31 species in both data sets, estimates of apparent survival were somewhat lower for 13, somewhat higher for 17, and remained unchanged for one; confidence intervals for estimates based on six and 12 years of data overlapped for all species. Results indicate that estimates of apparent survival are comparable but more precise when based on longer-term data sets; standard error of the estimates was negatively correlated with numbers of captures (rs?=??0.72) and recaptures (rs?=??0.93, P<0.001 in both cases). Thus, reasonable estimates of apparent survival may be obtained with relatively few years of data if sample sizes are sufficient. PMID:24312519

  20. Quantum engineering of apparent tunneling height in ultra thin Pb films

    NASA Astrophysics Data System (ADS)

    Kim, Jungdae; Qin, Shengyong; Shih, Chih-Kang Ken

    2008-03-01

    The thickness dependence of tunneling decay constant (?) for ultra thin Pb films is studied with various sample biases by using low temperature STM. It is found that quantum well states (QWS) have a strong influence on the tunneling decay constant ?. While the decay constant versus layer thickness (? vs. L) clearly shows bilayer oscillations, we found that the apparent contrast in ? vs. L also show strong bias dependence. Depending on the bias voltage, contrast reversal in the apparent oscillation of ? vs. L can be precisely tuned when the tunneling into the sample empty states. This result also shows that ?-oscillation does not necessarily imply the work function oscillation. We further show that in this case, the parallel component of crystal momentum plays a critical role in tunneling process and is largely responsible for the observed phenomena. On the other hand, at negative sample bias, we show that the measured decay constants well reflect the variation of surface workfunction. In this case, the layer-dependent surface work functions indeed show bi-layer oscillations and the signature of phase slip due to non-perfect phase matching between Fermi wavelength and the vertical lattice constant.

  1. Line tension and reduction of apparent contact angle associated with electric double layers

    E-print Network

    Aaron Dörr; Steffen Hardt

    2014-11-05

    The line tension of an electrolyte wetting a non-polar substrate is computed analytically and numerically. The results show that, depending on the value of the apparent contact angle, positive or negative line tension values may be obtained. Furthermore, a significant difference between Young's contact angle and the apparent contact angle measured several Debye lengths remote from the three-phase contact line occurs. When applying the results to water wetting highly charged surfaces, line tension values of the same order of magnitude as found in recent experiments can be achieved. Therefore, the theory presented may contribute to the understanding of line tension measurements and points to the importance of the electrostatic line tension. Being strongly dependent on the interfacial charge density, electrostatic line tension is found to be tunable via the pH value of the involved electrolyte. As a practical consequence, the stability of nanoparticles adsorbed at fluid-fluid interfaces is predicted to be dependent on the pH value. The theory is suited for future incorporation of effects due to surfactants where even larger line tension values can be expected.

  2. Line tension and reduction of apparent contact angle associated with electric double layers

    NASA Astrophysics Data System (ADS)

    Dörr, Aaron; Hardt, Steffen

    2014-08-01

    The line tension of an electrolyte wetting a non-polar substrate is computed analytically and numerically. The results show that, depending on the value of the apparent contact angle, positive or negative line tension values may be obtained. Furthermore, a significant difference between Young's contact angle and the apparent contact angle measured several Debye lengths remote from the three-phase contact line occurs. When applying the results to water wetting highly charged surfaces, line tension values of the same order of magnitude as found in recent experiments can be achieved. Therefore, the theory presented may contribute to the understanding of line tension measurements and points to the importance of the electrostatic line tension. Being strongly dependent on the interfacial charge density, electrostatic line tension is found to be tunable via the pH value of the involved electrolyte. As a practical consequence, the stability of nanoparticles adsorbed at fluid-fluid interfaces is predicted to be dependent on the pH value. The theory is suited for future incorporation of effects due to surfactants where even larger line tension values can be expected.

  3. Effect of surface fissure on apparent resistivity measurements

    NASA Astrophysics Data System (ADS)

    Sailhac, P.; Gance, J.; Malet, J.

    2013-12-01

    Fissures are features of interest, prone to create preferential flow path, modifying locally the soil hydrogeological behavior. Electrical Resistivity Tomography (ERT) is a suitable tool to monitor such preferential flow path. However, this technique is not efficient in the presence of surface fissure, due to a bad resistivity recovering around the fissure vicinity during the inversion process. Therefore, we propose a description of fissure effect on raw apparent resistivity on three resistivity arrays. The purposes of the study are multiple. First, we aim at making ERT users aware of surface fissure effect, and propose a first help to interpret basically resistivity pseudo sections. Second, we propose to ERT users to automatically conduct a surface fissure survey on the studied profile, in order to consider each fissure in a forward DC model and to suppress their effect. Finally, this study is only a first step toward 2D fissure shape inversion, and time-lapse monitoring of fissure drying and filling. In this study, we create a fissure model based on different geomorphological descriptors. After describing the FEM-DC forward modeling strategy, we investigate the fissure effect on pseudo section of apparent resistivity for a Wenner-Schlumberger (WS), a dipole-dipole (DD) and a gradient (GRAD) array. We determine a fissure detectability threshold for each array and perform a sensitivity analysis on the different fissure parameters (position, width, depth, dip angles...). The crack filling or drying effect is also investigated. The possibility to remove fissure effect and to propose a first interpretation of time-lapse data is illustrated on real data. This study show again the higher sensitivity of the DD array compared to the GRAD and WS arrays. Not only the maximal amplitude in the pseudo section is higher for the DD array, but also the anomaly pattern created by the fissure is much larger for this acquisition geometry. The minimal depth detectable for the DD array is 0.1 times the electrode spacing, and 0.16 for the GRAD and WS arrays. Globally, fissure opening width and dip angle have little impact compared to the fissure depth which can make vary apparent resistivity for more than 200 %. Apparent resistivities quantitative and qualitative interpretation is very difficult in this case and fissure geometry effect must be removed from apparent resistivity pseudo-section. The fissure water filling tends to suppress linearly the topographic effect with the percentage of filling. The conductive effect, produced by the addition of conductive water in the fissure, interacts constructively with fissure effect, but is less pronounced (maximum 15 % compared to the 60% of the fissure shape effect).

  4. Dynamics of false vacuum bubbles: beyond the thin shell approximation

    E-print Network

    Jakob Hansen; Dong-il Hwang; Dong-han Yeom

    2009-11-08

    We numerically study the dynamics of false vacuum bubbles which are inside an almost flat background; we assumed spherical symmetry and the size of the bubble is smaller than the size of the background horizon. According to the thin shell approximation and the null energy condition, if the bubble is outside of a Schwarzschild black hole, unless we assume Farhi-Guth-Guven tunneling, expanding and inflating solutions are impossible. In this paper, we extend our method to beyond the thin shell approximation: we include the dynamics of fields and assume that the transition layer between a true vacuum and a false vacuum has non-zero thickness. If a shell has sufficiently low energy, as expected from the thin shell approximation, it collapses (Type 1). However, if the shell has sufficiently large energy, it tends to expand. Here, via the field dynamics, field values of inside of the shell slowly roll down to the true vacuum and hence the shell does not inflate (Type 2). If we add sufficient exotic matters to regularize the curvature near the shell, inflation may be possible without assuming Farhi-Guth-Guven tunneling. In this case, a wormhole is dynamically generated around the shell (Type 3). By tuning our simulation parameters, we could find transitions between Type 1 and Type 2, as well as between Type 2 and Type 3. Between Type 2 and Type 3, we could find another class of solutions (Type 4). Finally, we discuss the generation of a bubble universe and the violation of unitarity. We conclude that the existence of a certain combination of exotic matter fields violates unitarity.

  5. A new approach to the "apparent survival" problem: estimating true survival rates from mark-recapture studies.

    PubMed

    Gilroy, James J; Virzi, Thomas; Boulton, Rebecca L; Lockwood, Julie L

    2012-07-01

    Survival estimates generated from live capture-mark-recapture studies may be negatively biased due to the permanent emigration of marked individuals from the study area. In the absence of a robust analytical solution, researchers typically sidestep this problem by simply reporting estimates using the term "apparent survival." Here, we present a hierarchical Bayesian multistate model designed to estimate true survival by accounting for predicted rates of permanent emigration. Initially we use dispersal kernels to generate spatial projections of dispersal probability around each capture location. From these projections, we estimate emigration probability for each marked individual and use the resulting values to generate bias-adjusted survival estimates from individual capture histories. When tested using simulated data sets featuring variable detection probabilities, survival rates, and dispersal patterns, the model consistently eliminated negative biases shown by apparent survival estimates from standard models. When applied to a case study concerning juvenile survival in the endangered Cape Sable Seaside Sparrow (Ammodramus maritimus mirabilis), bias-adjusted survival estimates increased more than twofold above apparent survival estimates. Our approach is applicable to any capture-mark-recapture study design and should be particularly valuable for organisms with dispersive juvenile life stages. PMID:22919897

  6. On negative inertial defect

    Microsoft Academic Search

    Takeshi Oka

    1995-01-01

    Morino's general formula for inertial defect has been applied to planar molecules with very low out-of-plane vibrations in order to explain negative inertial defects reported for such molecules. The obtained simple formula is combined with an empirical proportionality relation between zero point inertial defect ?0 and ?Icc for ordinary molecules to give semi-empirical relations between the inertial defect ?0, the

  7. Evaluating Negative Benefits

    E-print Network

    Beedles, William L.

    1978-03-01

    is consistent with the con- 2 elusions of Robichek and Myers (hereafter, R and M) [3 and 4] . However, the example above illustrates the limited generality of the R and M works, limited in the sense that they considered only the special type of benefits with...]. Using this, they claim that increasing risk causes the factors 2 An anonymous referee pointed out the importance of emphasizing these observations. 174 to decrease in magnitude. However, negative projected benefits have certainty equivalent factors...

  8. Algebra Balance Scales - Negatives

    NSDL National Science Digital Library

    Utah State University

    2009-07-01

    This site provides a virtual balance on which the student can represent (and then solve) simple linear equations with integer answers. Conceptually, positive weights (unit-blocks and x-boxes) push the pans of the scale downward. Negative values are represented by balloons which can be attached to the pans of the scale. The student can then manipulate the weights to solve the equation while simultaneously seeing a visual display of these effects on the equation.

  9. Double-negative acoustic metamaterial

    NASA Astrophysics Data System (ADS)

    Li, Jensen; Chan, C. T.

    2004-11-01

    We show here the existence of acoustic metamaterial, in which both the effective density and bulk modulus are simultaneously negative, in the true and strict sense of an effective medium. Our double-negative acoustic system is an acoustic analogue of Veselago’s medium in electromagnetism, and shares many unique consequences, such as negative refractive index. The double negativity in acoustics is derived from low-frequency resonances, as in the case of electromagnetism, but the negative density and modulus are derived from a single resonance structure as distinct from electromagnetism in which the negative permeability and negative permittivity originates from different resonance mechanisms.

  10. Possible Meteorites in the Martian Hills (False Color)

    NASA Technical Reports Server (NTRS)

    2006-01-01

    From its winter outpost at 'Low Ridge' inside Gusev Crater, NASA's Mars Exploration Rover Spirit took this spectacular, color mosaic of hilly, sandy terrain and two potential iron meteorites. The two light-colored, smooth rocks about two-thirds of the way up from the bottom of the frame have been labeled 'Zhong Shan' and 'Allan Hills.'

    The two rocks' informal names are in keeping with the rover science team's campaign to nickname rocks and soils in the area after locations in Antarctica. Zhong Shang is an Antarctic base that the People's Republic of China opened on Feb. 26, 1989, at the Larsemann Hills in Prydz Bay in East Antarctica. Allan Hills is a location where researchers have found many Martian meteorites, including the controversial ALH84001, which achieved fame in 1996 when NASA scientists suggested that it might contain evidence for fossilized extraterrestrial life. Zhong Shan was the given name of Dr. Sun Yat-sen (1866-1925), known as the 'Father of Modern China.' Born to a peasant family in Guangdong, Sun moved to live with his brother in Honolulu at age 13 and later became a medical doctor. He led a series of uprisings against the Qing dynasty that began in 1894 and eventually succeeded in 1911. Sun served as the first provisional president when the Republic of China was founded in 1912.

    The Zhong Shan and Allan Hills rocks, at the left and right, respectively, have unusual morphologies and miniature thermal emission spectrometer signatures that resemble those of a rock known as 'Heat Shield' at the Meridiani site explored by Spirit's twin, Opportunity. Opportunity's analyses revealed Heat Shield to be an iron meteorite.

    Spirit acquired this false-color image on the rover's 872nd Martian day, or sol (June 16, 2006), using exposures taken through three of the panoramic camera's filters, centered on wavelengths of 750 nanometers, 530 nanometers, and 430 nanometers. The image is presented in false color to emphasize differences among materials in the rocks and soil.

  11. Discovery of Two Apparent Novae in M81

    NASA Astrophysics Data System (ADS)

    Hornoch, K.; McCormac, J.; Vaduvescu, O.

    2013-06-01

    We report the discovery of two apparent novae in the M81 galaxy on a co-added 1600-s, narrow-band H-alpha CCD image taken with the 2.5-m Isaac Newton Telescope (INT) + WFC at La Palma in ~1.5" seeing on 2013 June 3.905 UT. The new objects are visible on individual 400-s frames and well visible on the co-added image (see the finding chart linked below), but are not present on numerous narrow-band H-alpha archival images from the INT down to a limiting magnitude as faint as H-alpha = 22.7.

  12. Discovery of an Apparent Nova in M81

    NASA Astrophysics Data System (ADS)

    Hornoch, K.; Vaduvescu, O.; Gonzalez, A.

    2013-04-01

    We report the discovery of an apparent nova in the M81 galaxy on a co-added 2000-s narrow-band H-alpha CCD image taken with the 2.5-m Isaac Newton Telescope (INT) + WFC at La Palma in ~1.4" seeing on Apr. 5.946 UT. The new object is visible on individual 400-s frames and well visible on the co-added image (see the finding chart linked below), but is not present on numerous narrow-band H-alpha archival images from the INT down to limiting magnitude as faint as H-alpha = 21.7.

  13. QT Interval Prolongation Predicts Cardiovascular Mortality inan Apparently Healthy Population

    Microsoft Academic Search

    Evert G. Schouten; Jacqueline M. Dekker; Peter Meppelink; Frans J. Kok

    2010-01-01

    Background. Inmyocardial infarction patients, heart rate-adjusted QT interval (QT), an electrocardiographic indicator ofsympathetic balance, isprognostic forsurvival. Methods andResults. Ina 28-year follow-up, theassociation betweenQT,andall-cause, cardiovascular, andischemic heartdisease mortality was studied ina population of3,091 apparently healthy Dutchcivil servants andtheir spouses,aged40-65 years,whoparticipated ina medical examination during 1953-1954. Moderate (QTc, 420-440 msec)andextensive (QTc, more than440msec)QTcprolongations significantly predict all-cause mortality during thefirst 15yearsamong men (adjusted

  14. Dynamics of the Cosmological Apparent Horizon: Surface Gravity & Temperature

    E-print Network

    Alexis Helou

    2015-02-14

    In the context of thermodynamics applied to our cosmological apparent horizon, we explicit in greater details our previous work which established the Friedmann Equations from projection of Hayward's Unified First Law. In particular, we show that the dynamical Hayward-Kodama surface gravity is perfectly well-defined and is suitable for this derivation. We then relate this surface gravity to a physical notion of temperature, and show this has constant, positive sign for any kind of past-inner trapping horizons. Hopefully this will clarify the choice of temperature in a dynamical Friedmann-Lema\\^itre-Roberston-Walker spacetime.

  15. False positive reactivity of recombinant, diagnostic, glycoproteins produced in High Five insect cells: effect of glycosylation.

    PubMed

    Hancock, Kathy; Narang, Someet; Pattabhi, Sowmya; Yushak, Melinda L; Khan, Azra; Lin, Seh-Ching; Plemons, Robert; Betenbaugh, Michael J; Tsang, Victor C W

    2008-01-31

    Baculovirus-mediated expression of recombinant proteins for use in diagnostic assays is commonplace. We expressed a diagnostic antigen for cysticercosis, GP50, caused by the larval stage of Taenia solium, in both High Five and Sf9 insect cells. Upon evaluation of the specificity of recombinant GP50 (rGP50) in a western blot assay, we observed that 12.5% (21/168) of the serum samples from persons with a variety of parasitic infections other than cysticercosis reacted positive when rGP50 was produced in High Five cells. The same samples reacted negative when rGP50 was produced in Sf9 cells. The false positive reactivities of these other parasitic infection sera were abolished when rGP50, expressed in High Five cells, was deglycosylated. In addition, the same sera that reacted with rGP50 from High Five cells also reacted with recombinant human transferrin (rhTf) when expressed in High Five cells, but not Sf9 cells. High Five cells, but not Sf9 cells, modify many glycoproteins with a core alpha(1,3)-fucose. This same modification is found in the glycoproteins of several parasitic worms and is known to be immunogenic. Since the distribution of these worms is widespread and millions of people are infected, the use of recombinant proteins with N-linked glycosylation produced in High Five cells for diagnostic antigens is likely to result in a number of false positive reactions and a decrease in assay specificity. PMID:17868684

  16. Six month impact of false positives in an Australian infant hearing screening programme

    PubMed Central

    Poulakis, Z; Barker, M; Wake, M

    2003-01-01

    Aims: To assess short and longer term parent reported impacts of false positive referrals in the Victorian Infant Hearing Screening Program (VIHSP). Methods: Mailed retrospective case-control survey of infants consecutively referred to VIHSP between December 1998 and April 1999 for whom audiology did not confirm permanent hearing loss, comprising 137 infants screened with a neonatal risk factor questionnaire and 148 older infants screened with two consecutive behavioural (distraction) tests. The two control groups comprised non-referred screened infants matched by domicile, age, and gender. Main outcome measures were parent reported emotions experienced before and after child's audiology test, parent estimated impact of hearing loss, the Child Vulnerability Scale, audiology assessment satisfaction questionnaire, and questions relating to their child's hearing and language development. Results: Final sample: at risk cases (AR) 108 (79% response), at risk controls 64 (51%); distraction test cases (DT) 103 (70%), distraction test controls 53 (41%). Parents across all groups believed that hearing loss would have major effects on a child's language (91–96%), schooling (81–91%), and employment opportunities (67–75%). Before audiology, 71% (AR) and 72% (DT) of case parents were anxious/worried, falling to 4% and 15% afterwards. After the test 82% (AR) and 79% (DT) reported relief, but 19% and 18% continued to feel worried. Ongoing concerns about hearing, language, development, and general health were comparable for AR cases compared to controls, and for DT cases compared to controls. Conclusions: Hearing screening tests are generally well received. Parents are realistic about the impact of childhood hearing loss and report a range of negative emotions when a false positive hearing screen requires referral. Although most are reassured by a normal test, a substantial number report continuing concern. PMID:12495952

  17. Stability of streambanks formed in partially saturated soils and effects of negative pore water pressures: the Sieve River (Italy)

    Microsoft Academic Search

    Massimo Rinaldi; Nicola Casagli

    1999-01-01

    Streambanks of alluvial channels are usually composed of loose materials, which are unsaturated in ambient conditions. Unsaturated soils are subject to negative pore water pressures, which cause an apparent cohesion. The latter is the main factor in allowing the stability of near-vertical banks. Even during moderate in-bank flow events, the apparent cohesion can be strongly reduced as the material approaches

  18. Underwater audiogram of a false killer whale (Pseudorca crassidens).

    PubMed

    Thomas, J; Chun, N; Au, W; Pugh, K

    1988-09-01

    Underwater audiograms are available for only a few odontocete species. A false killer whale (Pseudorca crassidens) was trained at Sea Life Park in Oahu, Hawaii for an underwater hearing test using a go/no-go response paradigm. Over a 6-month period, auditory thresholds from 2-115 kHz were measured using an up/down staircase psychometric technique. The resulting audiogram showed hearing sensitivities below 64 kHz similar to those of belugas (Delphinapterus leucas) and Atlantic bottlenosed dolphins (Tursiops truncatus). Above 64 kHz, this Pseudorca had a rapid decrease in sensitivity of about 150 dB per octave. A similar decrease in sensitivity occurs at 32 kHz in the killer whale, at 50 kHz in the Amazon River dolphin, at 120 kHz in the beluga, at 140 kHz in the bottlenosed dolphin, and at 140 kHz in the harbor porpoise. The most sensitive range of hearing was from 16-64 kHz (a range of 10 dB from the maximum sensitivity). This range corresponds with the peak frequency of echolocation pulses recorded from captive Pseudorca. PMID:3183211

  19. 'Gibson' Panorama by Spirit at 'Home Plate' (False Color)

    NASA Technical Reports Server (NTRS)

    2006-01-01

    NASA's Mars Exploration Rover Spirit acquired this high-resolution view of intricately layered exposures of rock while parked on the northwest edge of the bright, semi-circular feature known as 'Home Plate.' The rover was perched at a 27-degree upward tilt while creating the panorama, resulting in the 'U' shape of the mosaic. In reality, the features along the 1-meter to 2-meter (1-foot to 6.5-foot) vertical exposure of the rim of Home Plate in this vicinity are relatively level. Rocks near the rover in this view, known as the 'Gibson' panorama, include 'Barnhill,' 'Rogan,' and 'Mackey.'

    Spirit acquired 246 separate images of this scene using 6 different filters on the panoramic camera (Pancam) during the rover's Martian days, or sols, 748 through 751 (Feb. 9 through Feb. 12, 2006). The field of view covers 160 degrees of terrain around the rover. This image is a false-color rendering using using Pancam's 753-nanometer, 535-namometer, and 432-nanometer filters, presented to enhance many subtle color differences between rocks and soils in the scene. Image-to-image seams have been eliminated from the sky portion of the mosaic to better simulate the vista a person standing on Mars would see.

  20. Development of pH-responsive fluorescent false neurotransmitters.

    PubMed

    Lee, Minhee; Gubernator, Niko G; Sulzer, David; Sames, Dalibor

    2010-07-01

    We introduce pH-responsive fluorescent false neurotransmitters (pH-responsive FFNs) as novel probes that act as vesicular monoamine transporter (VMAT) substrates and ratiometric fluorescent pH sensors. The development of these agents was achieved by systematic molecular design that integrated several structural elements, including the aminoethyl group (VMAT recognition), halogenated hydroxy-coumarin core (ratiometric optical pH sensing in the desired pH range), and N- or C-alkylation (modulation of lipophilicity). Of 14 compounds that were synthesized, the probe Mini202 was selected based on the highest uptake in VMAT2-transfected HEK cells and desirable optical properties. Using Mini202, we measured the pH of catecholamine secretory vesicles in PC-12 cells (pH approximately 5.9) via two-photon fluorescence microscopy. Incubation with methamphetamine led to an increase in vesicular pH (pH approximately 6.4), consistent with a proposed mechanism of action of this psychostimulant, and eventually to redistribution of vesicular content (including Mini202) from vesicles to cytoplasm. Mini202 is sufficiently bright, photostable, and suitable for two-photon microscopy. This probe will enable fundamental neuroscience and neuroendocrine research as well as drug screening efforts. PMID:20540519

  1. False-Positive Head-Impulse Test in Cerebellar Ataxia

    PubMed Central

    Kremmyda, Olympia; Kirchner, Hanni; Glasauer, Stefan; Brandt, Thomas; Jahn, Klaus; Strupp, Michael

    2012-01-01

    The objective of this study was to compare the findings of the bedside head-impulse test (HIT), passive head rotation gain, and caloric irrigation in patients with cerebellar ataxia (CA). In 16 patients with CA and bilaterally pathological bedside HIT, vestibuloocular reflex (VOR) gains were measured during HIT and passive head rotation by scleral search coil technique. Eight of the patients had pathologically reduced caloric responsiveness, while the other eight had normal caloric responses. Those with normal calorics showed a slightly reduced HIT gain (mean?±?SD: 0.73?±?0.15). In those with pathological calorics, gains 80 and 100?ms after the HIT as well as the passive rotation VOR gains were significantly lower. The corrective saccade after head turn occurred earlier in patients with pathological calorics (111?±?62?ms after onset of the HIT) than in those with normal calorics (191?±?17?ms, p?=?0.0064). We identified two groups of patients with CA: those with an isolated moderate HIT deficit only, probably due to floccular dysfunction, and those with combined HIT, passive rotation, and caloric deficit, probably due to a peripheral vestibular deficit. From a clinical point of view, these results show that the bedside HIT alone can be false-positive for establishing a diagnosis of a bilateral peripheral vestibular deficit in patients with CA. PMID:23162531

  2. After Attempted Sample Delivery on Sol 60, False Color

    NASA Technical Reports Server (NTRS)

    2008-01-01

    This view from the Surface Stereo Imager on NASA's Phoenix Mars Lander on the mission's 60th Martian day, or sol, (July 26, 2008) was taken after the lander's scoop sprinkled a soil sample over Thermal and Evolved-Gas Analyzer (TEGA).

    The upper part of the picture shows the robotic arm scoop parked open-face down above the TEGA after delivery. The TEGA doors farthest to the right were open to receive the sample into one of TEGA's eight ovens. Not enough material reached the oven to allow an analysis to begin. Some of the soil sample can be seen at the bottom of the adjacent pair of doors.

    This view is presented in false color, which makes the reddish color of the soil-sample material easy to see.

    The Phoenix Mission is led by the University of Arizona, Tucson, on behalf of NASA. Project management of the mission is by NASA's Jet Propulsion Laboratory, Pasadena, Calif. Spacecraft development is by Lockheed Martin Space Systems, Denver.

  3. Three frequency false-color image of Prince Albert, Canada

    NASA Technical Reports Server (NTRS)

    1994-01-01

    This is a three-frequency, false color image of Prince Albert, Canada, centered at 53.91 north latitude and 104.69 west longitude. It was produced using data from the X-band, C-band and L-band radars that comprise the Spaceborne Imaging Radar-C/X-band Synthetic Aperture Radar (SIR-C/X-SAR). SIR-C/X-SAR acquired this image on the 20th orbit of the Shuttle Endeavour. The area is located 40 km north and 30 km east of the town of Prince Albert in the Saskatchewan province of Canada. The image covers the area east of the Candle Lake, between gravel surface highways 120 and 106 and west of 106. The area in the middle of the image covers the entire Nipawin (Narrow Hills) provincial park. Most of the dark blue areas in the image are the ice covered lakes. The dark area on the top right corner of the image is the White Gull Lake north of the intersection of highway 120 and 913. The right middle part of the image shows Lake Ispuchaw and Lower Fishing Lake. The deforested areas are shown by light

  4. False-color composite image of Prince Albert, Canada

    NASA Technical Reports Server (NTRS)

    1994-01-01

    This is a false color composite of Prince Albert, Canada, centered at 53.91 north latitude and 104.69 west longitude. This image was acquired by the Spaceborne Imaging Radar-C/X-band Synthetic Aperture Radar (SIR-C/X-SAR) on the 20th orbit of the Shuttle Endeavour. The area is located 40 km north and 30 km east of the town of Prince Albert in the Saskatchewan province of Canada. The image covers the area east of the Candle Lake, between gravel surface highways 120 and 106 and west of 106. The area in the middle of the image covers the entire Nipawin (Narrow Hills) provincial park. The look angle of the radar is 30 degrees and the size of the image is approximately 20 kilometers by 50 kilometers (12 by 30 miles). Most of the dark areas in the image are the ice-covered lakes in the region. The dark area on the top right corner of the image is the White Gull Lake north of the intersection of Highway 120 and 913. The right middle part of the image shows Lake Ispuchaw and Lower Fishing Lake

  5. HOME INSECURITY: NO ALARMS, FALSE ALARMS, AND SIGINT

    SciTech Connect

    Lamb, Logan M [ORNL

    2014-01-01

    The market share of home security systems has substantially increased as vendors incorporate more desirable features: intrusion detection, automation, wireless, and LCD touch panel controls. Wireless connectivity allows vendors to manufacture cheaper, more featureful products that require little to no home modification to install. Consumer win, since adding devices is easier. The result: an ostensibly more secure, convenient, and connected home for a larger number of citizens. Sadly, this hypothesis is flawed; the idea of covering a home with more security sensors does not translate into a more secure home. Additionally, the number of homes using these vulnerable systems is large, and the growth rate is increasing producing a even larger problem. In this talk, I will demonstrate a generalized approach for compromising three systems: ADT, the largest home security dealer in North America; Honeywell, one of the largest manufacturers of security devices; and Vivint, a top 5 security dealer. We will suppress alarms, create false alarms, and collect artifacts that facilitate tracking the movements of individuals in their homes.

  6. Novel insights into false recollection: a model of déjà vécu.

    PubMed

    O'Connor, Akira R; Lever, Colin; Moulin, Chris J A

    2010-01-01

    The thesis of this paper is that déjà experiences can be separated into two forms: déjà vu, arising from the erroneous sensation of familiarity, and déjà vécu, arising from the erroneous sensation of recollection. We summarise a series of cases for whom déjà vécu is experienced frequently and for extended periods, and seek to differentiate their experiences from "healthy" déjà experiences by non-brain-damaged participants. In reviewing our cases, we stress two novel ideas: that déjà vécu in these cases is delusion-like; and that these cases experience déjà vécu for stimuli that are especially novel or unusual. Here we present a novel cognitive neuroscientific hypothesis of déjà vécu. This hypothesis assumes that the signal of retrieval from memory is neurally dissociable from the contents of retrieval. We suggest that a region downstream of the hippocampus signals "recollection" by detecting the timing of firing in hippocampal output neurons relative to the theta oscillation. Disruptions to this "temporal coding" mechanism result in false signals of recollection which may occur without actual retrieval and which, ironically, may arise particularly during situations of contextual novelty. PMID:20394115

  7. Three frequency false color image of Flevoland, the Netherlands

    NASA Technical Reports Server (NTRS)

    1994-01-01

    This is a three-frequency false color image of Flevoland, the Netherlands, centered at 52.4 degrees north latitude, 5.4 degrees east longitude. This image was acquired by the Spaceborne Imaging Radar-C and X-Band Synthetic Aperture Radar (SIR-C/X-SAR) aboard the Shuttle Endeavour. The area shown covers an area approximately 25 kilometers by 28 kilometers. Flevoland, which fills the lower two-thirds of the image, is a very flat area that is made up of reclaimed land that is used for agriculture and forestry. At the top of the image, across the canal from Flevoland, is an older forest shown in red; the city of Harderwijk is shown in white on the shore of the canal. At this time of the year, the agricultural fields are bare soil, and they show up in this image in blue. The dark blue areas are water and the small dots in the canal are boats. The Jet Propulsion Laboratory alternative photo number is P-43941.

  8. True and false symmetries in the classification of optical scatterers

    NASA Astrophysics Data System (ADS)

    Crosta, Giovanni F.; Videen, Gorden

    2014-05-01

    A plane wave is scattered by a potential of bounded support. Translation, rotation and reflection of the potential, q0 induce transformations of the scattered wave. The latter can be represented by means of Born sequences, where q0 appears under the integral sign: non-local formulas are thus derived, the properties of which are discussed. Next, the symmetries induced by the 1st BORN approximation are addressed. Invariance of the squared modulus of the scattering amplitude holds for translation and reflection. The transformation T? := 13 +?3?=1??A?, with {??;} real and {A?} the generators of rotations in IR3, is investigated. Conditions on the {? ?} are derived, by which the scattering amplitude coming from the first BORN approximation is invariant to T?. As an application, these "false symmetries" are compared to those induced by limited angular resolution of a detector in light scattering experiments. Namely, scattering patterns are made available by the TAOS (Two-dimensional Angle-resolved Optical Scattering) method, which consists of detecting single airborne aerosol particles and collecting the intensity of the light they scatter from a pulsed, monochromatic laser beam. The optics and the detector properties determine the resolution at which a pattern is saved. The implications on the performance of TAOS pattern analysis are briefly discussed.

  9. Sulfur-Rich Rocks and Dirt (False Color)

    NASA Technical Reports Server (NTRS)

    2005-01-01

    NASA's Mars Rover Spirit has been analyzing sulfur-rich rocks and surface materials in the 'Columbia Hills' in Gusev Crater on Mars. This image of a very soft, nodular, layered rock nicknamed 'Peace' in honor of Martin Luther King Jr. shows a 4.5-centimeter-wide (1.8-inch-wide) hole Spirit ground into the surface with the rover's rock abrasion tool. The high sulfur content of the rock measured by Spirit's alpha particle X-ray spectrometer and its softness measured by the abrasion tool are probably evidence of past alteration by water. Spirit's panoramic camera took this false-color image on martian day, or sol, 381 (Jan. 27, 2005), using Pancam filters at wavelengths of 750, 530, and 430 nanometers. Darker red hues in the image correspond to greater concentrations of oxidized soil and dust. Bluer hues correspond to sulfur-rich rock excavated or exposed by the abrasion tool and not as heavily coated with soils or not as highly oxidized.

  10. The 'Appar' Flax Release: Origin, Distinguishing Characteristics, And Use; And A Native Alternative

    Microsoft Academic Search

    Rosemary L Pendleton; Stanley G Kitchen; E Durant McArthur; Joann E Mudge

    2008-01-01

    This article summarizes information on the taxonomy of 'Appar', a perennial blue flax cultivar (Linum perenne L. [Linaceae]), and characteristics that distinguish it from native Lewis flax (Linum lewisii Pursh [Linaceae]). 'Appar' apparently originated as a European flax that escaped from garden cultivation. Randomly amplified polymorphic DNA (RAPD) analysis places 'Appar' with other collections of European Linum perenne and separates

  11. Measurement of the B stretchy="false">¯s0?Ds-Ds+ and B stretchy="false">¯s0?D-Ds+ Effective Lifetimes

    NASA Astrophysics Data System (ADS)

    Aaij, R.; Adeva, B.; Adinolfi, M.; Affolder, A.; Ajaltouni, Z.; Albrecht, J.; Alessio, F.; Alexander, M.; Ali, S.; Alkhazov, G.; Alvarez Cartelle, P.; Alves, A. A., Jr.; Amato, S.; Amerio, S.; Amhis, Y.; Anderlini, L.; Anderson, J.; Andreassen, R.; Andreotti, M.; Andrews, J. E.; Appleby, R. B.; Aquines Gutierrez, O.; Archilli, F.; Artamonov, A.; Artuso, M.; Aslanides, E.; Auriemma, G.; Baalouch, M.; Bachmann, S.; Back, J. J.; Badalov, A.; Balagura, V.; Baldini, W.; Barlow, R. J.; Barschel, C.; Barsuk, S.; Barter, W.; Batozskaya, V.; Bauer, Th.; Bay, A.; Beddow, J.; Bedeschi, F.; Bediaga, I.; Belogurov, S.; Belous, K.; Belyaev, I.; Ben-Haim, E.; Bencivenni, G.; Benson, S.; Benton, J.; Berezhnoy, A.; Bernet, R.; Bettler, M.-O.; van Beuzekom, M.; Bien, A.; Bifani, S.; Bird, T.; Bizzeti, A.; Bjørnstad, P. M.; Blake, T.; Blanc, F.; Blouw, J.; Blusk, S.; Bocci, V.; Bondar, A.; Bondar, N.; Bonivento, W.; Borghi, S.; Borgia, A.; Borsato, M.; Bowcock, T. J. V.; Bowen, E.; Bozzi, C.; Brambach, T.; van den Brand, J.; Bressieux, J.; Brett, D.; Britsch, M.; Britton, T.; Brook, N. H.; Brown, H.; Bursche, A.; Busetto, G.; Buytaert, J.; Cadeddu, S.; Calabrese, R.; Callot, O.; Calvi, M.; Calvo Gomez, M.; Camboni, A.; Campana, P.; Campora Perez, D.; Carbone, A.; Carboni, G.; Cardinale, R.; Cardini, A.; Carranza-Mejia, H.; Carson, L.; Carvalho Akiba, K.; Casse, G.; Castillo Garcia, L.; Cattaneo, M.; Cauet, Ch.; Cenci, R.; Charles, M.; Charpentier, Ph.; Cheung, S.-F.; Chiapolini, N.; Chrzaszcz, M.; Ciba, K.; Cid Vidal, X.; Ciezarek, G.; Clarke, P. E. L.; Clemencic, M.; Cliff, H. V.; Closier, J.; Coca, C.; Coco, V.; Cogan, J.; Cogneras, E.; Collins, P.; Comerma-Montells, A.; Contu, A.; Cook, A.; Coombes, M.; Coquereau, S.; Corti, G.; Couturier, B.; Cowan, G. A.; Craik, D. C.; Cruz Torres, M.; Cunliffe, S.; Currie, R.; D'Ambrosio, C.; Dalseno, J.; David, P.; David, P. N. Y.; Davis, A.; De Bonis, I.; De Bruyn, K.; De Capua, S.; De Cian, M.; De Miranda, J. M.; De Paula, L.; De Silva, W.; De Simone, P.; Decamp, D.; Deckenhoff, M.; Del Buono, L.; Déléage, N.; Derkach, D.; Deschamps, O.; Dettori, F.; Di Canto, A.; Dijkstra, H.; Donleavy, S.; Dordei, F.; Dorosz, P.; Dosil Suárez, A.; Dossett, D.; Dovbnya, A.; Dupertuis, F.; Durante, P.; Dzhelyadin, R.; Dziurda, A.; Dzyuba, A.; Easo, S.; Egede, U.; Egorychev, V.; Eidelman, S.; van Eijk, D.; Eisenhardt, S.; Eitschberger, U.; Ekelhof, R.; Eklund, L.; El Rifai, I.; Elsasser, Ch.; Falabella, A.; Färber, C.; Farinelli, C.; Farry, S.; Ferguson, D.; Fernandez Albor, V.; Ferreira Rodrigues, F.; Ferro-Luzzi, M.; Filippov, S.; Fiore, M.; Fiorini, M.; Fitzpatrick, C.; Fontana, M.; Fontanelli, F.; Forty, R.; Francisco, O.; Frank, M.; Frei, C.; Frosini, M.; Furfaro, E.; Gallas Torreira, A.; Galli, D.; Gandelman, M.; Gandini, P.; Gao, Y.; Garofoli, J.; Garosi, P.; Garra Tico, J.; Garrido, L.; Gaspar, C.; Gauld, R.; Gersabeck, E.; Gersabeck, M.; Gershon, T.; Ghez, Ph.; Gianelle, A.; Gibson, V.; Giubega, L.; Gligorov, V. V.; Göbel, C.; Golubkov, D.; Golutvin, A.; Gomes, A.; Gordon, H.; Grabalosa Gándara, M.; Graciani Diaz, R.; Granado Cardoso, L. A.; Graugés, E.; Graziani, G.; Grecu, A.; Greening, E.; Gregson, S.; Griffith, P.; Grillo, L.; Grünberg, O.; Gui, B.; Gushchin, E.; Guz, Yu.; Gys, T.; Hadjivasiliou, C.; Haefeli, G.; Haen, C.; Hafkenscheid, T. W.; Haines, S. C.; Hall, S.; Hamilton, B.; Hampson, T.; Hansmann-Menzemer, S.; Harnew, N.; Harnew, S. T.; Harrison, J.; Hartmann, T.; He, J.; Head, T.; Heijne, V.; Hennessy, K.; Henrard, P.; Hernando Morata, J. A.; van Herwijnen, E.; Heß, M.; Hicheur, A.; Hill, D.; Hoballah, M.; Hombach, C.; Hulsbergen, W.; Hunt, P.; Huse, T.; Hussain, N.; Hutchcroft, D.; Hynds, D.; Iakovenko, V.; Idzik, M.; Ilten, P.; Jacobsson, R.; Jaeger, A.; Jans, E.; Jaton, P.; Jawahery, A.; Jing, F.; John, M.; Johnson, D.; Jones, C. R.; Joram, C.; Jost, B.; Jurik, N.; Kaballo, M.; Kandybei, S.; Kanso, W.; Karacson, M.; Karbach, T. M.; Kenyon, I. R.; Ketel, T.; Khanji, B.; Klaver, S.; Kochebina, O.; Komarov, I.; Koopman, R. F.; Koppenburg, P.; Korolev, M.; Kozlinskiy, A.; Kravchuk, L.; Kreplin, K.; Kreps, M.; Krocker, G.; Krokovny, P.; Kruse, F.; Kucharczyk, M.; Kudryavtsev, V.; Kurek, K.; Kvaratskheliya, T.; La Thi, V. N.; Lacarrere, D.; Lafferty, G.; Lai, A.; Lambert, D.; Lambert, R. W.; Lanciotti, E.; Lanfranchi, G.; Langenbruch, C.; Latham, T.; Lazzeroni, C.; Le Gac, R.; van Leerdam, J.; Lees, J.-P.; Lefèvre, R.; Leflat, A.; Lefrançois, J.; Leo, S.; Leroy, O.; Lesiak, T.; Leverington, B.; Li, Y.; Liles, M.; Lindner, R.; Linn, C.; Lionetto, F.; Liu, B.; Liu, G.; Lohn, S.; Longstaff, I.; Lopes, J. H.; Lopez-March, N.; Lowdon, P.; Lu, H.; Lucchesi, D.; Luisier, J.; Luo, H.; Luppi, E.; Lupton, O.; Machefert, F.; Machikhiliyan, I. V.; Maciuc, F.; Maev, O.; Malde, S.

    2014-03-01

    The first measurement of the effective lifetime of the B stretchy="false">¯s0 meson in the decay B stretchy="false">¯s0?Ds-Ds+ is reported using a proton-proton collision data set, corresponding to an integrated luminosity of 3 fb-1, collected by the LHCb experiment. The measured value of the B stretchy="false">¯s0?Ds-Ds+ effective lifetime is 1.379±0.026±0.017 ps, where the uncertainties are statistical and systematic, respectively. This lifetime translates into a measurement of the decay width of the light B stretchy="false">¯s0 mass eigenstate of ?L=0.725±0.014±0.009 ps-1. The B stretchy="false">¯s0 lifetime is also measured using the flavor-specific B stretchy="false">¯s0?D-Ds+ decay to be 1.52±0.15±0.01 ps.

  12. Negative spherical perceptron

    E-print Network

    Mihailo Stojnic

    2013-06-17

    In this paper we consider the classical spherical perceptron problem. This problem and its variants have been studied in a great detail in a broad literature ranging from statistical physics and neural networks to computer science and pure geometry. Among the most well known results are those created using the machinery of statistical physics in \\cite{Gar88}. They typically relate to various features ranging from the storage capacity to typical overlap of the optimal configurations and the number of incorrectly stored patterns. In \\cite{SchTir02,SchTir03,TalBook} many of the predictions of the statistical mechanics were rigorously shown to be correct. In our own work \\cite{StojnicGardGen13} we then presented an alternative way that can be used to study the spherical perceptrons as well. Among other things we reaffirmed many of the results obtained in \\cite{SchTir02,SchTir03,TalBook} and thereby confirmed many of the predictions established by the statistical mechanics. Those mostly relate to spherical perceptrons with positive thresholds (which we will typically refer to as the positive spherical perceptrons). In this paper we go a step further and attack the negative counterpart, i.e. the perceptron with negative thresholds. We present a mechanism that can be used to analyze many features of such a model. As a concrete example, we specialize our results for a particular feature, namely the storage capacity. The results we obtain for the storage capacity seem to indicate that the negative case could be more combinatorial in nature and as such a somewhat harder challenge than the positive counterpart.

  13. Pore fluid pressure, apparent friction, and Coulomb failure

    USGS Publications Warehouse

    Beeler, N.M.; Simpson, R.W.; Hickman, S.H.; Lockner, D.A.

    2000-01-01

    Many recent studies of stress-triggered seismicity rely on a fault failure model with a single free parameter, the apparent coefficient of friction, presumed to be a material constant with possible values 0 ? ?? ? 1. These studies may present a misleading view of fault strength and the role of pore fluid pressure in earthquake failure. The parameter ?? is intended to incorporate the effects of both friction and pore pressure, but is a material constant only if changes in pore fluid pressure induced by changes in stress are proportional to the normal stress change across the potential failure plane. Although specific models of fault zones permit such a relation, neither is it known that fault zones within the Earth behave this way, nor is this behavior expected in all cases. In contrast, for an isotropic homogeneous poroelastic model the pore pressure changes are proportional to changes in mean stress, ?? is not a material constant, and ?? ? ?? ? +?. Analysis of the change in Coulomb failure stress for tectonically loaded reverse and strike-slip faults shows considerable differences between these two pore pressure models, suggesting that such models might be distinguished from one another using observations of triggered seismicity (e.g., aftershocks). We conclude that using the constant apparent friction model exclusively in studies of Coulomb failure stress is unwise and could lead to significant errors in estimated stress change and seismic hazard.

  14. Modelling apparent low thermal inertia by layered structure

    NASA Astrophysics Data System (ADS)

    Yoshida, Akari; Toyota, Takenori; Kurita, Kei

    2013-04-01

    Thermal inertia of planetary surface is a physical property that controls the diurnal and seasonal cycles in the surface temperature. At the same time it provides a unique window into geologic structure of the surface and the nature of geologic processes that shapes the planetary surface. Especially on Mars, it has been extensively derived from spacecraft remote-sensing observations. It shows existence of the area with very low thermal inertia in the equatorial and middle latitudes, which at the same time display complicated heterogeneous characteristics(Putzig and Mellon, 2007). This is one of the enigma about the surface state of Mars. Physical interpretation about the origin of this heterogeneous nature of the thermal inertia is needed. In this study, we discuss a possibility of apparent low thermal inertia when there exists a layered structure having contrasting thermal conductivities based on laboratory experiments. The layered structure we examined in the experiments are an acrylic plate(3.2mm , 5mm , 10mm in thickness) on top of Polystyrene foam block or vesiculated particle layer. In both cases the lower layer has lower thermal conductivity. They are heated periodically by a infrared lump from above(period from 10 to 600 sec.). We measured the temperature at the surface, bottom of the acrylic plate and inside the lower Polystyrene foam and the granular layer using the thermocouples and infrared thermometer. From amplitude of temperature variation, we estimated the thermal inertia. The important controlling factor in this experimental design is a thermal relaxation time of the surface layer, which is controlled by period of the applied heating cycle and the thickness. At the fixed layer thickness thermal structure changes drastically between the periods below and above the relaxation time. We estimated variation of apparent thermal inertia with period. In a homogeneous semi-infinite layer the amplitude of variation of the surface temperature induced by periodic heating under controlled situation is proportional to square root of the period and inversely proportional to the thermal inertia(Wang et al 2010). We utilized their formula to determine apparent thermal inertia. At the periods below thermal relaxation time unique value for thermal inertia was obtained while above the relaxation time it decreases even below the value of the lower layer. This is caused by the effect of finite layer thickness,which reduces thermal gradient in the surface layer. This leads to apparent low thermal inertia value. In our experiments we can demonstrate a simple layered structure; a thin layer having higher thermal conductivity on top of a layer with low thermal conductivity can produce apparent low thermal inertia. In the martian situation the thermal inertia is obtained mostly by diurnal heating cycle, which has a penetration depth(Thermal relaxation depth) of several to 10 cm. We discuss several geological processes to produce layered structure in this depth range in the presentation.

  15. A case of immunohistochemical false positive staining caused by incompatibility between a CD4 antibody and an autostainer

    PubMed Central

    Matsuda, Ikuo; Sugihara, Nao; Yunokizaki, Hiroshi; Abe, Takashi; Hirota, Seiichi

    2015-01-01

    Precise immunophenotyping of tumor cells by immunohistochemistry is complementary to morphological examination. It is critical for the correct histopathological diagnosis of lymphomas. In this paper, we report a case of T-cell lymphoma whose histopathological diagnosis was confounded by an immunohistochemical pitfall: a false positive caused by incompatibility between an antibody and an autostainer. In this case, based on CD4 immunohistochemistry of the affected lymph nodes, the T-cell lymphoma was diagnosed as CD4-positive at the onset, while it appeared discordantly to be CD4-negative at the second relapse. We noticed that CD4 antibodies and autostainers of different suppliers (designated as suppliers X and Y) were used in an unqualified combination in immunohistochemistry at the onset: that is, the combination of an antibody supplied by X and an autostainer supplied by Y (designated as X-Y combination) was used at the onset. On the other hand, the Y-Y combination was at the second relapse. At the second relapse, flow cytometry of the affected lymph node showed infiltration of CD4-negative T-cell lymphoma. We reasoned that CD4 immunonegativity obtained by the Y-Y combination at the second relapse was specific, while CD4 immunopositivity by the X-Y combination at the onset was false positive. Immunohistochemical reexamination of the lymph node at the onset proved to be CD4-negative by not only the Y-Y but also X-X combinations, confirming our final diagnosis of nodal relapse of CD4-negative T-cell lymphoma. This case illustrates the importance of using compatible combinations of antibodies and autostainers in diagnostic immunohistochemistry. PMID:25755812

  16. Polarized negative ions

    SciTech Connect

    Haeberli, W.

    1981-04-01

    This paper presents a survey of methods, commonly in use or under development, to produce beams of polarized negative ions for injection into accelerators. A short summary recalls how the hyperfine interaction is used to obtain nuclear polarization in beams of atoms. Atomic-beam sources for light ions are discussed. If the best presently known techniques are incorporated in all stages of the source, polarized H/sup -/ and D/sup -/ beams in excess of 10 ..mu..A can probably be achieved. Production of polarized ions from fast (keV) beams of polarized atoms is treated separately for atoms in the H(25) excited state (Lamb-Shift source) and atoms in the H(1S) ground state. The negative ion beam from Lamb-Shift sources has reached a plateau just above 1 ..mu..A, but this beam current is adequate for many applications and the somewhat lower beam current is compensated by other desirable characteristics. Sources using fast polarized ground state atoms are in a stage of intense development. The next sections summarize production of polarized heavy ions by the atomic beam method, which is well established, and by optical pumping, which has recently been demonstrated to yield very large nuclear polarization. A short discussion of proposed ion sources for polarized /sup 3/He/sup -/ ions is followed by some concluding remarks.

  17. Southern Half of Spirit's 'Bonestell' Panorama (False Color)

    NASA Technical Reports Server (NTRS)

    2008-01-01

    This 180-degree panorama shows the southward vista from the location where Spirit is spending its third Martian winter inside Mars' Gusev Crater. The rover's overwintering location is on the northern edge of a low plateau informally called 'Home Plate,' which is about 80 meters or 260 feet in diameter.

    This view combines 168 different exposures taken with Spirit's panoramic Camera (Pancam) 42 pointings with 4 filters at each pointing. Spirit took the first of these frames during the mission's 1,477th Martian day, or sol, (February 28, 2008) two weeks after the rover made its last move to reach the location where it would stop driving for the winter. Solar energy at Gusev Crater is so limited during the Martian winter that Spirit does not generate enough electricity to drive, nor even enough to take many images per day. The last frame for this mosaic was taken on Sol 1599 (July 2, 2008). The rover team plans for Spirit to finish taking images for the northern half of the scene during the Martian spring.

    The northwestern edge of Home Plate is visible in the right foreground. The blockier, more sharply shadowed texture there is layered sandstone whose layering is tilted inward toward the edge of the Home Plate platform. A dark rock on top of Home Plate in that area is a porous volcanic basalt unlike rocks nearby. The northeastern edge of Home Plate is visible in the left foreground. Spirit first climbed onto Home Plate on that region, in early 2006.

    Rover tracks from driving by Spirit are visible on Home plate in the center and right of the image. These were made during Spirit's second exploration on top of the plateau, which began when Spirit climbed onto the southern edge of Home Plate in September, 2007.

    In the center foreground, the turret of tools at the end of Spirit's robotic arm appears in duplicate because the arm was repositioned between the days when the images making up that part of the mosaic were taken.

    On the horizon, the highest point is 'McCool Hill.' This is one of the seven larger hills in the Columbia Hills range. Home Plate is in the inner basin of the range, between McCool Hill to the south and 'Husband Hill' to the north. To the right of McCool Hill, in the center of the image and closer to Home Plate, is a smaller hill capped with a light-toned outcrop. This hill is called 'Von Braun,' and it is a possible destination the rover team has discussed for the next season of driving by Spirit, after the solar energy level increases in the Martian spring. The flat horizon in the right-hand portion of the panorama is the basaltic plain onto which Spirit landed on Jan. 4, 2004.

    This is a false-color, red-green-blue composite panorama generated from images taken through the Pancam's 750-nanometer, 530-nanometer and 430-nanometer filters. The false color enhances visibility of differences among the types of rock and soil material in the image.

  18. A false killer whale adjusts its hearing when it echolocates.

    PubMed

    Nachtigall, Paul E; Supin, Alexander Y

    2008-06-01

    The use of auditory evoked potential (AEP) measurements has added considerably to knowledge of the hearing mechanisms of marine mammals. We have recently measured the hearing of a stranded infant Risso's dolphin, the audiograms of white-beaked dolphins temporarily caught and released, and the hearing of anaesthetized polar bears. Most small toothed whales echolocate and hear very high frequency sounds underwater. While much has previously been learned about the echolocation performance and characteristics of the outgoing signals of echolocating dolphins and small whales, the hearing processes occurring while these animals actively echolocate have not previously been examined. Working with a well-trained echolocating false killer whale (Pseudorca crassidens) wearing latex surface suction cup electrodes, we have measured echolocation hearing AEPs in response to outgoing echolocation clicks, returning echoes, and comparable simulated whale clicks and echoes in a variety of situations. We have found that: (1) the whale may hear her loud outgoing clicks and much quieter returning echoes at comparable levels, (2) the whale has protective mechanisms that dampen the intensity of her outgoing signals - she hears her outgoing signals at a level about 40 dB lower than similar signals presented directly in front of her, (3) when echo return levels are lowered either by making the targets smaller or by placing the targets farther away - without changing the levels of her outgoing signals - the hearing of these echoes remains at almost the same level, (4) if targets are made much smaller and harder to echolocate, the animal will modify what she hears of her outgoing signal - as if to heighten overall hearing sensitivity to keep the echo level hearable, (5) the animal has an active 'automatic gain control' mechanism in her hearing based on both forward masking that balances outgoing pulse intensity and time between pulse and echo, and active hearing control. Overall, hearing during echolocation appears to be a very active process. PMID:18490386

  19. Why perversion?: 'False love' and the perverse pact.

    PubMed

    Stein, Ruth

    2005-06-01

    In this paper, the author works with the awareness that perversion is a socially, historically and theologically loaded term, at the same time as it may be the latest frontier in psychoanalysis, both clinically, and in relation to contemporary art and culture which emphasize the perverse. Positioning itself against tendencies to deny the existence of a category of 'perversion' or, inversely, to abuse it for the power that accrues from the act of diagnosing, she also points to other liabilities in the history of the treatment of this term, such as the narrowing down of perversion to the exclusively sexual domain, or, alternatively, the overextension of it to polymorphously erotic practices that enhance sexual excitement. The paradoxes of perversion and the difficulties of distinguishing the perverse from the non-perverse are addressed. The case is also made that, in order to understand perversion, one must unlink it from the narrow notion of sexual practice and see what is involved on a deeper level--an approach initiated when psychoanalysis turned to perversion as a defense against psychotic anxieties, and began considering the necessary place of perversion in the transference--countertransference. Two features common to both sexual and non-sexual perverse relations are the seductive and bribing aspects of perversion, and its means-ends reversal. Perversion is a haven for the disguising of hatred and suspicion as excitement and (false) love. Displaced child and beating father, entitled child and seductive mother, are both prototypes of psychoanalytic reflection on parents who excite, deceive and corrupt their children and establish perverse pacts with them. The notion of the perverse pact is foregrounded in Alice's analysis, where first the resurrection and then the dismantling of such a pact were effected through various analytic means. PMID:16096075

  20. Burrow-generated false facies and phantom sequences

    SciTech Connect

    Wanless, H.R.; Tagett, M.

    1986-05-01

    Callianassa (=Ophiomorpha) and other burrowers deeply rework shallow marine sequences. Through in-situ reworking, they create false sedimentary facies and stratigraphic sequences. Callianassa's key to effectiveness is that it expels sand and mud from burrow excavations but concentrates coarse material at the base of the burrow complex. Coarse material can be derived by falling into the burrow entrance, by reworking the existing sediment sequence, or by a combination of both. Examples come from shallow marine carbonate environments of south Florida and the Turks and Caicos Islands, British West Indies. Many mudbanks in south Florida are formed as stacks of layered mudstone units 20-100 cm thick. Between events, seagrasses may recolonize, and a burrowing benthic community may repopulate the substrate. The layered mudstone beneath older areas of mudbank flats can gradually be converted to a bioturbated skeletal wackestone by the deep burrowing community. Burrowing also causes mixing of faunal assemblages. On Caicos Bank, an extensive carbonate tidal flat (3-4 m thick) is slowly being transgressed. About 1 m of tidal-flat sequence is eroded at the shoreline. The remaining 2-3 m could be preserved as part of the transgressive sequence. Callianassa burrowing, however, quickly reworks the sequence, replacing tidal-flat sands and muds with marine peloidal and skeletal sediment. Within 100 m of the shoreline, the only evidence of the tidal-flat sequence is a concentration of high-spired gastropods in Calliannassa burrows at the base of the Holocene sequence and a few patches of tidal-flat sediment that burrowers missed. What looks like a basal transgressive lag is in fact a biogenic concentrate from in-situ reworking of a now phantom sequence.

  1. Ice Layer Cross-Section In False Color

    NASA Technical Reports Server (NTRS)

    2005-01-01

    [figure removed for brevity, see original site]

    The theme for the weeks of 1/17 and 1/24 is the north polar region of Mars as seen in false color THEMIS images. Ice/frost will typically appear as bright blue in color; dust mantled ice will appear in tones of red/orange.

    This image of shows a cross sectional view of the ice layers. Note the subtle peach banding on the left side of the image. The time variation that the bands represent is not yet understood.

    Image information: VIS instrument. Latitude 83.5, Longitude 118.2 East (241.8 West). 19 meter/pixel resolution.

    Note: this THEMIS visual image has not been radiometrically nor geometrically calibrated for this preliminary release. An empirical correction has been performed to remove instrumental effects. A linear shift has been applied in the cross-track and down-track direction to approximate spacecraft and planetary motion. Fully calibrated and geometrically projected images will be released through the Planetary Data System in accordance with Project policies at a later time.

    NASA's Jet Propulsion Laboratory manages the 2001 Mars Odyssey mission for NASA's Office of Space Science, Washington, D.C. The Thermal Emission Imaging System (THEMIS) was developed by Arizona State University, Tempe, in collaboration with Raytheon Santa Barbara Remote Sensing. The THEMIS investigation is led by Dr. Philip Christensen at Arizona State University. Lockheed Martin Astronautics, Denver, is the prime contractor for the Odyssey project, and developed and built the orbiter. Mission operations are conducted jointly from Lockheed Martin and from JPL, a division of the California Institute of Technology in Pasadena.

  2. Veillonella, Firmicutes: Microbes disguised as Gram negatives

    PubMed Central

    Vesth, Tammi; Ozen, Asl?; Andersen, Sandra C.; Kaas, Rolf Sommer; Lukjancenko, Oksana; Bohlin, Jon; Nookaew, Intawat; Wassenaar, Trudy M.; Ussery, David W.

    2013-01-01

    The Firmicutes represent a major component of the intestinal microflora. The intestinal Firmicutes are a large, diverse group of organisms, many of which are poorly characterized due to their anaerobic growth requirements. Although most Firmicutes are Gram positive, members of the class Negativicutes, including the genus Veillonella, stain Gram negative. Veillonella are among the most abundant organisms of the oral and intestinal microflora of animals and humans, in spite of being strict anaerobes. In this work, the genomes of 24 Negativicutes, including eight Veillonella spp., are compared to 20 other Firmicutes genomes; a further 101 prokaryotic genomes were included, covering 26 phyla. Thus a total of 145 prokaryotic genomes were analyzed by various methods to investigate the apparent conflict of the Veillonella Gram stain and their taxonomic position within the Firmicutes. Comparison of the genome sequences confirms that the Negativicutes are distantly related to Clostridium spp., based on 16S rRNA, complete genomic DNA sequences, and a consensus tree based on conserved proteins. The genus Veillonella is relatively homogeneous: inter-genus pair-wise comparison identifies at least 1,350 shared proteins, although less than half of these are found in any given Clostridium genome. Only 27 proteins are found conserved in all analyzed prokaryote genomes. Veillonella has distinct metabolic properties, and significant similarities to genomes of Proteobacteria are not detected, with the exception of a shared LPS biosynthesis pathway. The clade within the class Negativicutes to which the genus Veillonella belongs exhibits unique properties, most of which are in common with Gram-positives and some with Gram negatives. They are only distantly related to Clostridia, but are even less closely related to Gram-negative species. Though the Negativicutes stain Gram-negative and possess two membranes, the genome and proteome analysis presented here confirm their place within the (mainly) Gram positive phylum of the Firmicutes. Further studies are required to unveil the evolutionary history of the Veillonella and other Negativicutes. PMID:24976898

  3. Veillonella, Firmicutes: Microbes disguised as Gram negatives.

    PubMed

    Vesth, Tammi; Ozen, Asl?; Andersen, Sandra C; Kaas, Rolf Sommer; Lukjancenko, Oksana; Bohlin, Jon; Nookaew, Intawat; Wassenaar, Trudy M; Ussery, David W

    2013-12-20

    The Firmicutes represent a major component of the intestinal microflora. The intestinal Firmicutes are a large, diverse group of organisms, many of which are poorly characterized due to their anaerobic growth requirements. Although most Firmicutes are Gram positive, members of the class Negativicutes, including the genus Veillonella, stain Gram negative. Veillonella are among the most abundant organisms of the oral and intestinal microflora of animals and humans, in spite of being strict anaerobes. In this work, the genomes of 24 Negativicutes, including eight Veillonella spp., are compared to 20 other Firmicutes genomes; a further 101 prokaryotic genomes were included, covering 26 phyla. Thus a total of 145 prokaryotic genomes were analyzed by various methods to investigate the apparent conflict of the Veillonella Gram stain and their taxonomic position within the Firmicutes. Comparison of the genome sequences confirms that the Negativicutes are distantly related to Clostridium spp., based on 16S rRNA, complete genomic DNA sequences, and a consensus tree based on conserved proteins. The genus Veillonella is relatively homogeneous: inter-genus pair-wise comparison identifies at least 1,350 shared proteins, although less than half of these are found in any given Clostridium genome. Only 27 proteins are found conserved in all analyzed prokaryote genomes. Veillonella has distinct metabolic properties, and significant similarities to genomes of Proteobacteria are not detected, with the exception of a shared LPS biosynthesis pathway. The clade within the class Negativicutes to which the genus Veillonella belongs exhibits unique properties, most of which are in common with Gram-positives and some with Gram negatives. They are only distantly related to Clostridia, but are even less closely related to Gram-negative species. Though the Negativicutes stain Gram-negative and possess two membranes, the genome and proteome analysis presented here confirm their place within the (mainly) Gram positive phylum of the Firmicutes. Further studies are required to unveil the evolutionary history of the Veillonella and other Negativicutes. PMID:24976898

  4. Using the DRM false memory recall paradigm to investigate hemispheric asymmetry and sex differences 

    E-print Network

    Bellamy, Katarina

    2005-01-01

    The purpose of this study was to replicate that of Ito’s (2001) in which hemispheric asymmetry was explored using a false recognition and list learning paradigm to induce high levels of false recall for semantically ...

  5. 15 CFR 265.4 - Making or giving of false reports.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ...TECHNOLOGY, GAITHERSBURG, MARYLAND, AND BOULDER AND FORT COLLINS, COLORADO General § 265.4 Making or giving of false...Nothing in this section shall affect the applicability of 18 U.S.C. 1001 regarding false, fictitious or fraudulent statements...

  6. 15 CFR 265.4 - Making or giving of false reports.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ...TECHNOLOGY, GAITHERSBURG, MARYLAND, AND BOULDER AND FORT COLLINS, COLORADO General § 265.4 Making or giving of false...Nothing in this section shall affect the applicability of 18 U.S.C. 1001 regarding false, fictitious or fraudulent statements...

  7. 15 CFR 265.4 - Making or giving of false reports.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ...TECHNOLOGY, GAITHERSBURG, MARYLAND, AND BOULDER AND FORT COLLINS, COLORADO General § 265.4 Making or giving of false...Nothing in this section shall affect the applicability of 18 U.S.C. 1001 regarding false, fictitious or fraudulent statements...

  8. 76 FR 42082 - Taking of Marine Mammals Incidental to Commercial Fishing Operations; False Killer Whale Take...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-07-18

    ...2009) summarized information on false killer whale sightings near Hawaii between 1989 and 2007, based on various survey methods, and provided evidence that the Hawaii Insular stock of false killer whales may have declined during the last...

  9. Random variability explains apparent global clustering of large earthquakes

    USGS Publications Warehouse

    Michael, A.J.

    2011-01-01

    The occurrence of 5 Mw ? 8.5 earthquakes since 2004 has created a debate over whether or not we are in a global cluster of large earthquakes, temporarily raising risks above long-term levels. I use three classes of statistical tests to determine if the record of M ? 7 earthquakes since 1900 can reject a null hypothesis of independent random events with a constant rate plus localized aftershock sequences. The data cannot reject this null hypothesis. Thus, the temporal distribution of large global earthquakes is well-described by a random process, plus localized aftershocks, and apparent clustering is due to random variability. Therefore the risk of future events has not increased, except within ongoing aftershock sequences, and should be estimated from the longest possible record of events.

  10. Experimental production of "septa" and apparent subdivision of muscle mitochondria.

    PubMed

    Duncan, C J; Greenaway, H C; Publicover, S J; Rudge, M F; Smith, J L

    1980-04-01

    The rapid formation (in less than 45 min) of internal septa and the apparent subdivision in situ of mitochondria for cardiac and skeletal muscle are described following a variety of experimental treatments. For example, the ionophore A23187, caffeine, DNP, ruthenium red, and the insecticide lindane have been applied to intact, glycerinated, and chemically skinned skeletal muscle fibers and to cardiac muscle strips from both amphibians and mammals. In some mitochondria, the two compartments are in the same configurations; in others they are different. The significance of these mitochondrial septa is discussed, and it is suggested that the findings are consistent with the hypothesis that a variety of experimental procedures can promote rapid mitochondrial division. PMID:6157680

  11. Species-barrier-independent prion replication in apparently resistant species

    NASA Astrophysics Data System (ADS)

    Hill, Andrew F.; Joiner, Susan; Linehan, Jackie; Desbruslais, Melanie; Lantos, Peter L.; Collinge, John

    2000-08-01

    Transmission of prions between mammalian species is thought to be limited by a "species barrier," which depends on differences in the primary structure of prion proteins in the infecting inoculum and the host. Here we demonstrate that a strain of hamster prions thought to be nonpathogenic for conventional mice leads to prion replication to high levels in such mice but without causing clinical disease. Prions pathogenic in both mice and hamsters are produced. These results demonstrate the existence of subclinical forms of prion infection with important public health implications, both with respect to iatrogenic transmission from apparently healthy humans and dietary exposure to cattle and other species exposed to bovine spongiform encephalopathy prions. Current definitions of the species barrier, which have been based on clinical end-points, need to be fundamentally reassessed.

  12. Thermodynamics of Evolving Lorentzian Wormhole at Apparent and Event Horizons

    NASA Astrophysics Data System (ADS)

    Debnath, Ujjal; Jamil, Mubasher; Myrzakulov, Ratbay; Akbar, M.

    2014-12-01

    We have investigated the non-static Lorentzian Wormhole model in presence of anisotropic pressure. We have presented some exact solutions of Einstein equations for anisotropic pressure case. Introducing two EoS parameters we have shown that these solutions give very rich dynamics of the universe yielding to the different expansion history of it in the r - direction and in the T - direction. The corresponding explicit forms of the shape function b( r) is presented.We have shown that the Einstein's field equations and unified first law are equivalent for the dynamical wormhole model. The first law of thermodynamics has been derived by using the Unified first law. The physical quantities including surface gravity and the temperature are derived for the wormhole. Here we have obtained all the results without any choice of the shape function. The validity of generalized second law (GSL) of thermodynamics has been examined at apparent and event horizons for the evolving Lorentzian wormhole.

  13. Solving the apparent diversity-accuracy dilemma of recommender systems

    PubMed Central

    Zhou, Tao; Kuscsik, Zoltán; Liu, Jian-Guo; Medo, Matúš; Wakeling, Joseph Rushton; Zhang, Yi-Cheng

    2010-01-01

    Recommender systems use data on past user preferences to predict possible future likes and interests. A key challenge is that while the most useful individual recommendations are to be found among diverse niche objects, the most reliably accurate results are obtained by methods that recommend objects based on user or object similarity. In this paper we introduce a new algorithm specifically to address the challenge of diversity and show how it can be used to resolve this apparent dilemma when combined in an elegant hybrid with an accuracy-focused algorithm. By tuning the hybrid appropriately we are able to obtain, without relying on any semantic or context-specific information, simultaneous gains in both accuracy and diversity of recommendations. PMID:20176968

  14. Progressive multifocal leukoencephalopathy in a patient without apparent immunosuppression

    PubMed Central

    2010-01-01

    An 80-year-old man with no history of an immune-compromising disorder was diagnosed with progressive multifocal leukoencephalopathy (PML). He presented with dysphagia and left-sided weakness; magnetic resonance imaging demonstrated marked signal abnormality in the subcortical white matter of the left frontal lobe and in the posterior limb of the right internal capsule. Polymerase chain reaction (PCR) analysis of the cerebrospinal fluid (CSF) was negative for John Cunningham (JC) virus. On brain biopsy, foamy macrophages infiltrating the white matter were identified, staining positive for anti-simian virus 40 antibodies. Postoperatively, PCR for JC viral DNA in the CSF was positive, establishing the diagnosis of PML. Extensive investigation for an occult immunocompromising disorder was negative. The patient's neurologic deficits rapidly increased throughout his hospital stay, and he died 3.5 months after his diagnosis. PMID:20920200

  15. Systematic Characterization of High Mass Accuracy Influence on False Discovery and Probability Scoring in Peptide Mass Fingerprinting

    PubMed Central

    Dodds, Eric D.; Clowers, Brian H.; Hagerman, Paul J.; Lebrilla, Carlito B.

    2009-01-01

    While the bearing of mass measurement error upon protein identification is sometimes underestimated, uncertainty in observed peptide masses unavoidably translates to ambiguity in subsequent protein identifications. While ongoing instrumental advances continue to make high accuracy mass spectrometry (MS) increasingly accessible, many proteomics experiments are still conducted with rather large mass error tolerances. Additionally, the ranking schemes of most protein identification algorithms do not include a meaningful incorporation of mass measurement error. This report provides a critical evaluation of mass error tolerance as it pertains to false positive peptide and protein associations resulting from peptide mass fingerprint (PMF) database searching. High accuracy, high resolution PMFs of several model proteins were obtained using matrix-assisted laser desorption/ionization Fourier transform ion cyclotron resonance mass spectrometry (MALDI-FTICR-MS). Varying levels of mass accuracy were simulated by systematically modulating the mass error tolerance of the PMF query and monitoring the effect on figures of merit indicating the PMF quality. Importantly, the benefits of decreased mass error tolerance are not manifest in Mowse scores when operating at tolerances in the low parts per million range, but become apparent with the consideration of additional metrics that are often overlooked. Furthermore, the outcomes of these experiments support the concept that false discovery is closely tied to mass measurement error in PMF analysis. Clear establishment of this relation demonstrates the need for mass error aware protein identification routines and argues for a more prominent contribution of high accuracy mass measurement to proteomic science. PMID:17980142

  16. Negative Optical Torque

    PubMed Central

    Chen, Jun; Ng, Jack; Ding, Kun; Fung, Kin Hung; Lin, Zhifang; Chan, C. T.

    2014-01-01

    Light carries angular momentum, and as such it can exert torques on material objects. Applications of these opto-mechanical effects were limited initially due to their smallness in magnitude, but later becomes powerful and versatile after the invention of laser. Novel and practical approaches for harvesting light for particle rotation have since been demonstrated, where the structure is always subjected to a positive optical torque along a certain axis if the incident angular momentum has a positive projection on the same axis. We report here an interesting phenomenon of “negative optical torque”, meaning that incoming photons carrying angular momentum rotate an object in the opposite sense. Surprisingly this can be realized quite straightforwardly in simple planar structures. Field retardation is a necessary condition and discrete rotational symmetry of material object plays an important role. The optimal conditions are explored and explained. PMID:25226863

  17. Primitive Virtual Negative Charge

    E-print Network

    Kiyoung Kim

    2008-11-04

    Physical fields, such as gravity and electromagnetic field, are interpreted as results from rearrangement of vacuum particles to get the equilibrium of net charge density and net mass density in 4-dimensional complex space. Then, both fields should interact to each other in that physical interaction is considered as a field-to-field interaction. Hence, Mass-Charge interaction is introduced with primitive-virtual negative charge defined for the mass. With the concept of Mass-Charge interaction electric equilibrium of the earth is discussed, especially about the electric field and magnetic field of the earth. For unsettled phenomena related with the earth's gravity, such as antigravity phenomenon, gravity anomalies during the solar eclipses, the connection between geomagnetic storms and earthquakes, etc., possible explanations are discussed.

  18. Primitive Virtual Negative Charge

    E-print Network

    Kim, Kiyoung

    2008-01-01

    Physical fields, such as gravity and electromagnetic field, are interpreted as results from rearrangement of vacuum particles to get the equilibrium of net charge density and net mass density in 4-dimensional complex space. Then, both fields should interact to each other in that physical interaction is considered as a field-to-field interaction. Hence, Mass-Charge interaction is introduced with primitive-virtual negative charge defined for the mass. With the concept of Mass-Charge interaction electric equilibrium of the earth is discussed, especially about the electric field and magnetic field of the earth. For unsettled phenomena related with the earth's gravity, such as antigravity phenomenon, gravity anomalies during the solar eclipses, the connection between geomagnetic storms and earthquakes, etc., possible explanations are discussed.

  19. Negative ion source

    DOEpatents

    Leung, K.N.; Ehlers, K.W.

    1984-12-04

    An ionization vessel is divided into an ionizing zone and an extraction zone by a magnetic filter. The magnetic filter prevents high-energy electrons from crossing from the ionizing zone to the extraction zone. A small positive voltage impressed on a plasma grid, located adjacent an extraction grid, positively biases the plasma in the extraction zone to thereby prevent positive ions from migrating from the ionizing zone to the extraction zone. Low-energy electrons, which would ordinarily be dragged by the positive ions into the extraction zone, are thereby prevented from being present in the extraction zone and being extracted along with negative ions by the extraction grid. Additional electrons are suppressed from the output flux using ExB drift provided by permanent magnets and the extractor grid electrical field. 14 figs.

  20. Negative ion source

    DOEpatents

    Leung, Ka-Ngo (Hercules, CA); Ehlers, Kenneth W. (Alamo, CA)

    1984-01-01

    An ionization vessel is divided into an ionizing zone and an extraction zone by a magnetic filter. The magnetic filter prevents high-energy electrons from crossing from the ionizing zone to the extraction zone. A small positive voltage impressed on a plasma grid, located adjacent an extraction grid, positively biases the plasma in the extraction zone to thereby prevent positive ions from migrating from the ionizing zone to the extraction zone. Low-energy electrons, which would ordinarily be dragged by the positive ions into the extraction zone, are thereby prevented from being present in the extraction zone and being extracted along with negative ions by the extraction grid. Additional electrons are suppressed from the output flux using ExB drift provided by permanent magnets and the extractor grid electrical field.