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Sample records for spot dbs technique

  1. Performance of the biomerieux DBS puncher and dried blood spots ...

    African Journals Online (AJOL)

    Introduction: The latest World Health Organization recommendations request viral load (VL) testing, if possible, for monitoring HIV-1 infections. However, the use of plasma is an obstacle to realize this test in sub-Saharan Africa. In this context, the dried blood spot (DBS) is an interesting tool for sample collections.

  2. Study of measurement of the alcohol biomarker phosphatidylethanol (PEth) in dried blood spot (DBS) samples and application of a volumetric DBS device.

    Science.gov (United States)

    Beck, Olof; Kenan Modén, Naama; Seferaj, Sabina; Lenk, Gabriel; Helander, Anders

    2018-04-01

    Phosphatidylethanol (PEth) is a group of phospholipids formed in cell membranes following alcohol consumption. PEth measurement in whole blood samples is established as a specific alcohol biomarker with clinical and medico-legal applications. This study further evaluated the usefulness of dried blood spot (DBS) samples collected on filter paper for PEth measurement. Specimens used were surplus volumes of venous whole blood sent for routine LC-MS/MS quantification of PEth 16:0/18:1, the major PEth homolog. DBS samples were prepared by pipetting blood on Whatman 903 Protein Saver Cards and onto a volumetric DBS device (Capitainer). The imprecision (CV) of the DBS sample amount based on area and weight measurements of spot punches were 23-28%. Investigation of the relationship between blood hematocrit and PEth concentration yielded a linear, positive correlation, and at around 1.0-1.5μmol/L PEth 16:0/18:1, the PEth concentration increased by ~0.1μmol/L for every 5% increase in hematocrit. There was a close agreement between the PEth concentrations obtained with whole blood samples and the corresponding results using Whatman 903 (PEth DBS =1.026 PEth WB +0.013) and volumetric device (PEth DBS =1.045 PEth WB +0.016) DBS samples. The CV of PEth quantification in DBS samples at concentrations≥0.05μmol/L were ≤15%. The present results further confirmed the usefulness of DBS samples for PEth measurement. Copyright © 2018 Elsevier B.V. All rights reserved.

  3. Usefulness of Dried Blood Spots (DBS) to perform hepatitis C virus genotyping in drug users in Senegal.

    Science.gov (United States)

    Ndiaye, O; Gozlan, J; Diop-Ndiaye, H; Sall, A S; Chapelain, S; Leprêtre, A; Maynart, M; Gueye, M; Lo, G; Thiam, M; Ba, I; Lacombe, K; Girard, P M; Mboup, S; Kane, C T

    2017-03-01

    The aim of this pilot study was to analyze the Hepatitis C Virus (HCV) genotypes circulating in Senegal among Drug User (DUs), using Dried Blood Spots (DBS) as RNA source for molecular assays. Heroin and/or cocaine users (n = 506) were recruited in Dakar from April to July 2011, using a Respondent Driven Sampling (RDS) method. DBS preparation consisted of five drops of whole blood from finger applied to a Whatman paper card. HCV infection was screened by the detection of anti-HCV antibodies, using a rapid immune-chromatographic test. HCV RNA was quantified on anti-HCV positive DBS, using the Abbott RealTime HCV® Genotyping was performed on DBS with detectable viral load with Versant® HCV Genotype 2.0 Assay (LiPA) and Abbott RealTime HCV Genotype II assay®. Among the 506 participants, 120 were tested as positive for anti-HCV antibodies and their samples were analyzed for HCV RNA viral load and genotype. Out of the 120 DBS tested, HCV RNA was detected on 25 (20.8%). The median viral load was 15,058 IU/ml (ranging from 710 to 766,740 IU/ml). All positive DBS were suitable for the genotyping assay, that showed a predominance of genotype 1 (21/25) including 16 genotypes 1a and 5 genotypes 1b. HCV genotype 1 prevails in a DU population in Dakar. DBS could be useful for HCV RNA genotyping, but optimal storage conditions should required avoiding RNA impairment. Acknowledging this limitation, DBS could be a great interest for detecting and genotyping HCV viremic patients. J. Med. Virol. 89:484-488, 2017. © 2015 Wiley Periodicals, Inc. © 2015 Wiley Periodicals, Inc.

  4. In-depth study of homogeneity in DBS using two different techniques: Results from the EBF DBS-microsampling consortium

    NARCIS (Netherlands)

    Cobb, Z.; Vries, R. de; Spooner, N.; Williams, S.; Staelens, L.; Doig, M.; Broadhurst, R.; Barfield, M.; Merbel, N. van de; Schmid, B.; Siethoff, C.; Ortiz, J.; Verheij, E.; Baar, B. van; White, S.; Timmerman, P.

    2013-01-01

    Background: At the start of their work, the European Bioanalysis Forum dried blood spots microsampling consortium did not form a dedicated team to investigate the spot homogeneity. However, two teams performed experiments that produced results relating to sample homogeneity. Results: The data, which

  5. Diagnostic accuracy of serological diagnosis of hepatitis C and B using dried blood spot samples (DBS: two systematic reviews and meta-analyses

    Directory of Open Access Journals (Sweden)

    Berit Lange

    2017-11-01

    Full Text Available Abstract Background Dried blood spots (DBS are a convenient tool to enable diagnostic testing for viral diseases due to transport, handling and logistical advantages over conventional venous blood sampling. A better understanding of the performance of serological testing for hepatitis C (HCV and hepatitis B virus (HBV from DBS is important to enable more widespread use of this sampling approach in resource limited settings, and to inform the 2017 World Health Organization (WHO guidance on testing for HBV/HCV. Methods We conducted two systematic reviews and meta-analyses on the diagnostic accuracy of HCV antibody (HCV-Ab and HBV surface antigen (HBsAg from DBS samples compared to venous blood samples. MEDLINE, EMBASE, Global Health and Cochrane library were searched for studies that assessed diagnostic accuracy with DBS and agreement between DBS and venous sampling. Heterogeneity of results was assessed and where possible a pooled analysis of sensitivity and specificity was performed using a bivariate analysis with maximum likelihood estimate and 95% confidence intervals (95%CI. We conducted a narrative review on the impact of varying storage conditions or limits of detection in subsets of samples. The QUADAS-2 tool was used to assess risk of bias. Results For the diagnostic accuracy of HBsAg from DBS compared to venous blood, 19 studies were included in a quantitative meta-analysis, and 23 in a narrative review. Pooled sensitivity and specificity were 98% (95%CI:95%–99% and 100% (95%CI:99–100%, respectively. For the diagnostic accuracy of HCV-Ab from DBS, 19 studies were included in a pooled quantitative meta-analysis, and 23 studies were included in a narrative review. Pooled estimates of sensitivity and specificity were 98% (CI95%:95–99 and 99% (CI95%:98–100, respectively. Overall quality of studies and heterogeneity were rated as moderate in both systematic reviews. Conclusion HCV-Ab and HBsAg testing using DBS compared to venous

  6. Diagnostic accuracy of detection and quantification of HBV-DNA and HCV-RNA using dried blood spot (DBS) samples - a systematic review and meta-analysis.

    Science.gov (United States)

    Lange, Berit; Roberts, Teri; Cohn, Jennifer; Greenman, Jamie; Camp, Johannes; Ishizaki, Azumi; Messac, Luke; Tuaillon, Edouard; van de Perre, Philippe; Pichler, Christine; Denkinger, Claudia M; Easterbrook, Philippa

    2017-11-01

    The detection and quantification of hepatitis B (HBV) DNA and hepatitis C (HCV) RNA in whole blood collected on dried blood spots (DBS) may facilitate access to diagnosis and treatment of HBV and HCV infection in resource-poor settings. We evaluated the diagnostic performance of DBS compared to venous blood samples for detection and quantification of HBV-DNA and HCV-RNA in two systematic reviews and meta-analyses on the diagnostic accuracy of HBV DNA and HCV RNA from DBS compared to venous blood samples. We searched MEDLINE, Embase, Global Health, Web of Science, LILAC and Cochrane library for studies that assessed diagnostic accuracy with DBS. Heterogeneity was assessed and where appropriate pooled estimates of sensitivity and specificity were generated using bivariate analyses with maximum likelihood estimates and 95% confidence intervals. We also conducted a narrative review on the impact of varying storage conditions or different cut-offs for detection from studies that undertook this in a subset of samples. The QUADAS-2 tool was used to assess risk of bias. In the quantitative synthesis for diagnostic accuracy of HBV-DNA using DBS, 521 citations were identified, and 12 studies met the inclusion criteria. Overall quality of studies was rated as low. The pooled estimate of sensitivity and specificity for HBV-DNA was 95% (95% CI: 83-99) and 99% (95% CI: 53-100), respectively. In the two studies that reported on cut-offs and limit of detection (LoD) - one reported a sensitivity of 98% for a cut-off of ≥2000 IU/ml and another reported a LoD of 914 IU/ml using a commercial assay. Varying storage conditions for individual samples did not result in a significant variation of results. In the synthesis for diagnostic accuracy of HCV-RNA using DBS, 15 studies met the inclusion criteria, and this included six additional studies to a previously published review. The pooled sensitivity and specificity was 98% (95% CI:95-99) and 98% (95% CI:95-99.0), respectively

  7. Diagnostic accuracy of serological diagnosis of hepatitis C and B using dried blood spot samples (DBS): two systematic reviews and meta-analyses.

    Science.gov (United States)

    Lange, Berit; Cohn, Jennifer; Roberts, Teri; Camp, Johannes; Chauffour, Jeanne; Gummadi, Nina; Ishizaki, Azumi; Nagarathnam, Anupriya; Tuaillon, Edouard; van de Perre, Philippe; Pichler, Christine; Easterbrook, Philippa; Denkinger, Claudia M

    2017-11-01

    Dried blood spots (DBS) are a convenient tool to enable diagnostic testing for viral diseases due to transport, handling and logistical advantages over conventional venous blood sampling. A better understanding of the performance of serological testing for hepatitis C (HCV) and hepatitis B virus (HBV) from DBS is important to enable more widespread use of this sampling approach in resource limited settings, and to inform the 2017 World Health Organization (WHO) guidance on testing for HBV/HCV. We conducted two systematic reviews and meta-analyses on the diagnostic accuracy of HCV antibody (HCV-Ab) and HBV surface antigen (HBsAg) from DBS samples compared to venous blood samples. MEDLINE, EMBASE, Global Health and Cochrane library were searched for studies that assessed diagnostic accuracy with DBS and agreement between DBS and venous sampling. Heterogeneity of results was assessed and where possible a pooled analysis of sensitivity and specificity was performed using a bivariate analysis with maximum likelihood estimate and 95% confidence intervals (95%CI). We conducted a narrative review on the impact of varying storage conditions or limits of detection in subsets of samples. The QUADAS-2 tool was used to assess risk of bias. For the diagnostic accuracy of HBsAg from DBS compared to venous blood, 19 studies were included in a quantitative meta-analysis, and 23 in a narrative review. Pooled sensitivity and specificity were 98% (95%CI:95%-99%) and 100% (95%CI:99-100%), respectively. For the diagnostic accuracy of HCV-Ab from DBS, 19 studies were included in a pooled quantitative meta-analysis, and 23 studies were included in a narrative review. Pooled estimates of sensitivity and specificity were 98% (CI95%:95-99) and 99% (CI95%:98-100), respectively. Overall quality of studies and heterogeneity were rated as moderate in both systematic reviews. HCV-Ab and HBsAg testing using DBS compared to venous blood sampling was associated with excellent diagnostic accuracy

  8. Simplifying sample pretreatment: application of dried blood spot (DBS) method to blood samples, including postmortem, for UHPLC-MS/MS analysis of drugs of abuse.

    Science.gov (United States)

    Odoardi, Sara; Anzillotti, Luca; Strano-Rossi, Sabina

    2014-10-01

    The complexity of biological matrices, such as blood, requires the development of suitably selective and reliable sample pretreatment procedures prior to their instrumental analysis. A method has been developed for the analysis of drugs of abuse and their metabolites from different chemical classes (opiates, methadone, fentanyl and analogues, cocaine, amphetamines and amphetamine-like substances, ketamine, LSD) in human blood using dried blood spot (DBS) and subsequent UHPLC-MS/MS analysis. DBS extraction required only 100μL of sample, added with the internal standards and then three droplets (30μL each) of this solution were spotted on the card, let dry for 1h, punched and extracted with methanol with 0.1% of formic acid. The supernatant was evaporated and the residue was then reconstituted in 100μL of water with 0.1% of formic acid and injected in the UHPLC-MS/MS system. The method was validated considering the following parameters: LOD and LOQ, linearity, precision, accuracy, matrix effect and dilution integrity. LODs were 0.05-1ng/mL and LOQs were 0.2-2ng/mL. The method showed satisfactory linearity for all substances, with determination coefficients always higher than 0.99. Intra and inter day precision, accuracy, matrix effect and dilution integrity were acceptable for all the studied substances. The addition of internal standards before DBS extraction and the deposition of a fixed volume of blood on the filter cards ensured the accurate quantification of the analytes. The validated method was then applied to authentic postmortem blood samples. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

  9. Comparing identified and statistically significant lipids and polar metabolites in 15-year old serum and dried blood spot samples for longitudinal studies: Comparing lipids and metabolites in serum and DBS samples

    Energy Technology Data Exchange (ETDEWEB)

    Kyle, Jennifer E. [Earth and Biological Sciences Directorate, Pacific Northwest National Laboratory, Richland WA USA; Casey, Cameron P. [Earth and Biological Sciences Directorate, Pacific Northwest National Laboratory, Richland WA USA; Stratton, Kelly G. [National Security Directorate, Pacific Northwest National Laboratory, Richland WA USA; Zink, Erika M. [Earth and Biological Sciences Directorate, Pacific Northwest National Laboratory, Richland WA USA; Kim, Young-Mo [Earth and Biological Sciences Directorate, Pacific Northwest National Laboratory, Richland WA USA; Zheng, Xueyun [Earth and Biological Sciences Directorate, Pacific Northwest National Laboratory, Richland WA USA; Monroe, Matthew E. [Earth and Biological Sciences Directorate, Pacific Northwest National Laboratory, Richland WA USA; Weitz, Karl K. [Earth and Biological Sciences Directorate, Pacific Northwest National Laboratory, Richland WA USA; Bloodsworth, Kent J. [Earth and Biological Sciences Directorate, Pacific Northwest National Laboratory, Richland WA USA; Orton, Daniel J. [Earth and Biological Sciences Directorate, Pacific Northwest National Laboratory, Richland WA USA; Ibrahim, Yehia M. [Earth and Biological Sciences Directorate, Pacific Northwest National Laboratory, Richland WA USA; Moore, Ronald J. [Earth and Biological Sciences Directorate, Pacific Northwest National Laboratory, Richland WA USA; Lee, Christine G. [Department of Medicine, Bone and Mineral Unit, Oregon Health and Science University, Portland OR USA; Research Service, Portland Veterans Affairs Medical Center, Portland OR USA; Pedersen, Catherine [Department of Medicine, Bone and Mineral Unit, Oregon Health and Science University, Portland OR USA; Orwoll, Eric [Department of Medicine, Bone and Mineral Unit, Oregon Health and Science University, Portland OR USA; Smith, Richard D. [Earth and Biological Sciences Directorate, Pacific Northwest National Laboratory, Richland WA USA; Burnum-Johnson, Kristin E. [Earth and Biological Sciences Directorate, Pacific Northwest National Laboratory, Richland WA USA; Baker, Erin S. [Earth and Biological Sciences Directorate, Pacific Northwest National Laboratory, Richland WA USA

    2017-02-05

    The use of dried blood spots (DBS) has many advantages over traditional plasma and serum samples such as smaller blood volume required, storage at room temperature, and ability for sampling in remote locations. However, understanding the robustness of different analytes in DBS samples is essential, especially in older samples collected for longitudinal studies. Here we analyzed DBS samples collected in 2000-2001 and stored at room temperature and compared them to matched serum samples stored at -80°C to determine if they could be effectively used as specific time points in a longitudinal study following metabolic disease. Four hundred small molecules were identified in both the serum and DBS samples using gas chromatograph-mass spectrometry (GC-MS), liquid chromatography-MS (LC-MS) and LC-ion mobility spectrometry-MS (LC-IMS-MS). The identified polar metabolites overlapped well between the sample types, though only one statistically significant polar metabolite in a case-control study was conserved, indicating degradation occurs in the DBS samples affecting quantitation. Differences in the lipid identifications indicated that some oxidation occurs in the DBS samples. However, thirty-six statistically significant lipids correlated in both sample types indicating that lipid quantitation was more stable across the sample types.

  10. The effect of hematocrit on bioanalysis of DBS: Results from the EBF DBS-microsampling consortium

    NARCIS (Netherlands)

    Vries, R. de; Barfield, M.; Merbel, N. van de; Schmid, B.; Siethoff, C.; Ortiz, J.; Verheij, E.; Baar, B. van; Cobb, Z.; White, S.; Timmerman, P.

    2013-01-01

    Background: The European Bioanalysis Forum dried blood spots (DBS)/microsampling consortium is reporting back from the experiments they performed on further documenting the potential hurdles of the DBS technology. This paper is focused on the impact of hematocrit changes on DBS analyses. Results:

  11. Performance characteristics of finger-stick dried blood spots (DBS on the determination of human immunodeficiency virus (HIV treatment failure in a pediatric population in Mozambique.

    Directory of Open Access Journals (Sweden)

    Joy Chang

    Full Text Available Quantitative plasma viral load (VL at 1000 copies /mL was recommended as the threshold to confirm antiretroviral therapy (ART failure by the World Health Organization (WHO. Because of ongoing challenges of using plasma for VL testing in resource-limited settings (RLS, especially for children, this study collected 717 DBS and paired plasma samples from children receiving ART ≥1 year in Mozambique and compared the performance of DBS using Abbott's VL test with a paired plasma sample using Roche's VL test. At a cut-off of 1000 copies/mL, sensitivity of DBS using Abbott DBS VL test was 79.9%, better than 71.0% and 63.9% at 3000 and 5000 copies/mL, respectively. Specificities were 97.6%, 98.8%, 99.3% at 1000, 3000, and 5000 copies/mL, respectively. The Kappa value at 1000 copies/mL, 0.80 (95% CI: 0.73, 0.87, was higher than 0.73 (95% CI: 0.66, 0.80 and 0.66 (95% CI: 0.59, 0.73 at 3000, 5000 copies/mL, respectively, also indicating better agreement. The mean difference between the DBS and plasma VL tests with 95% limits of agreement by Bland-Altman was 0.311 (-0.908, 1.530. Among 73 children with plasma VL between 1000 to 5000 copies/mL, the DBS results were undetectable in 53 at the 1000 copies/mL threshold. While one DBS sample in the Abbott DBS VL test may be an alternative method to confirm ART failure at 1000 copies/mL threshold when a plasma sample is not an option for treatment monitoring, because of sensitivity concerns between 1,000 and 5,000 copies/ml, two DBS samples may be preferred accompanied by careful patient monitoring and repeat testing.

  12. dbs-arsenazo

    African Journals Online (AJOL)

    IV) catalyzes the discoloring reaction of DBS-arsenazo oxidized by potassium bromate, a new catalytic kinetic spectrophotometric method for the determination of trace titanium (IV) was developed. The linear range of the determination of ...

  13. Investigation of Reduction of the Uncertainty of Monte Carlo Dose Calculations in Oncor® Clinical Linear Accelerator Simulation Using the DBS Variance Reduction Technique in Monte Carlo Code BEAMnrc

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    Amin Asadi

    2017-10-01

    Full Text Available Purpose: To study the benefits of Directional Bremsstrahlung Splitting (DBS dose variance reduction technique in BEAMnrc Monte Carlo (MC code for Oncor® linac at 6MV and 18MV energies. Materials and Method: A MC model of Oncor® linac was built using BEAMnrc MC Code and verified by the measured data for 6MV and 18MV energies of various field sizes. Then Oncor® machine was modeled running DBS technique, and the efficiency of total fluence and spatial fluence for electron and photon, the efficiency of dose variance reduction of MC calculations for PDD on the central beam axis and lateral dose profile across the nominal field was measured and compared. Result: With applying DBS technique, the total fluence of electron and photon increased in turn 626.8 (6MV and 983.4 (6MV, and 285.6 (18MV and 737.8 (18MV, the spatial fluence of electron and photon improved in turn 308.6±1.35% (6MV and 480.38±0.43% (6MV, and 153±0.9% (18MV and 462.6±0.27% (18MV. Moreover, by running DBS technique, the efficiency of dose variance reduction for PDD MC dose calculations before maximum dose point and after dose maximum point enhanced 187.8±0.68% (6MV and 184.6±0.65% (6MV, 156±0.43% (18MV and 153±0.37% (18MV, respectively, and the efficiency of MC calculations for lateral dose profile remarkably on the central beam axis and across the treatment field raised in turn 197±0.66% (6MV and 214.6±0.73% (6MV, 175±0.36% (18MV and 181.4±0.45% (18MV. Conclusion: Applying dose variance reduction technique of DBS for modeling Oncor® linac with using BEAMnrc MC Code surprisingly improved the fluence of electron and photon, and it therefore enhanced the efficiency of dose variance reduction for MC calculations. As a result, running DBS in different kinds of MC simulation Codes might be beneficent in reducing the uncertainty of MC calculations. 

  14. Aflatoxin B1-lysine adduct in dried blood spot samples of animals and humans.

    Science.gov (United States)

    Xue, Kathy S; Cai, Wenjie; Tang, Lili; Wang, Jia-Sheng

    2016-12-01

    Dried blood spots (DBS) were proposed as potentially viable method for exposure assessment of environmental toxicants in infant and young children. For this study, we validated an experimental protocol to quantify AFB 1 -lysine adduct in DBS samples of AFB 1 -treated F344 rats, as well as samples from human field study. Significant dose-response relationships in AFB 1 -lysine adduct formation were found in DBS samples of rats treated with single- and repeated-dose AFB 1 . AFB 1 -lysine levels in DBS samples were highly correlated with corresponding serum sample levels. The Person coefficients were 0.997 for the single-dose exposure, and 0.996 for the repeated-dose exposure. Levels of AFB 1 -lysine adduct had also good agreement between DBS and serum samples as shown by Bland-Altman plot analysis. For human field study samples (n = 36), a Pearson correlation coefficient of 0.784 was found between AFB 1 -lysine adduct levels of DBS and corresponding serum samples. Bland-Altman plots showed the distribution of the log differences between DBS and serum AFB 1 -lysine levels are within 95% confidence intervals. These results showed AFB 1 -lysine adduct levels in DBS cards and serum samples from animals and human samples are comparable, and the DBS technique and analytical protocol is a good means to assess AFB 1 exposure in infant and children populations. Copyright © 2016 Elsevier Ltd. All rights reserved.

  15. The CMS DBS Query Language

    CERN Document Server

    Kuznetsov, Valentin; Afaq, Anzar; Sekhri, Vijay; Guo, Yuyi; Lueking, Lee

    2009-01-01

    The CMS experiment has implemented a flexible and powerful system enabling users to find data within the CMS physics data catalog. The Dataset Bookkeeping Service (DBS) comprises a database and the services used to store and access metadata related to CMS physics data. To this, we have added a generalized query system in addition to the existing web and programmatic interfaces to the DBS. This query system is based on a query language that hides the complexity of the underlying database structure by discovering the join conditions between database tables. This provides a way of querying the system that is simple and straightforward for CMS data managers and physicists to use without requiring knowledge of the database tables or keys. The DBS Query Language uses the ANTLR tool to build the input query parser and tokenizer, followed by a query builder that uses a graph representation of the DBS schema to construct the SQL query sent to underlying database. We will describe the design of the query system, provid...

  16. A modified micro chamber agar spot slide culture technique for microscopic examination of filamentous fungi.

    Science.gov (United States)

    Prakash, Peralam Yegneswaran; Bhargava, Kanika

    2016-04-01

    The slide culture technique aids in the study of undisturbed microscopic morphological details of filamentous fungi. The existing methods for setting up of slide culture are quite cumbersome, time-consuming and require elaborate preparation. We describe a modified and easy to perform micro chamber agar spot slide culture technique. Copyright © 2016 Elsevier B.V. All rights reserved.

  17. Spot-Bonding and Full-Bonding Techniques for Fiber Reinforced Composite (FRC) and Metallic Retainers

    Science.gov (United States)

    Gandini, Paola; Tessera, Paola; Vallittu, Pekka K.; Lassila, Lippo; Sfondrini, Maria Francesca

    2017-01-01

    Fiber reinforced Composite (FRC) retainers have been introduced as an aesthetic alternative to conventional metallic splints, but present high rigidity. The purpose of the present investigation was to evaluate bending and fracture loads of FRC splints bonded with conventional full-coverage of the FRC with a composite compared with an experimental bonding technique with a partial (spot-) resin composite cover. Stainless steel rectangular flat, stainless steel round, and FRC retainers were tested at 0.2 and 0.3 mm deflections and at a maximum load. Both at 0.2 and 0.3 mm deflections, the lowest load required to bend the retainer was recorded for spot-bonded stainless steel flat and round wires and for spot-bonded FRCs, and no significant differences were identified among them. Higher force levels were reported for full-bonded metallic flat and round splints and the highest loads were recorded for full-bonded FRCs. At the maximum load, no significant differences were reported among spot- and full-bonded metallic splints and spot-bonded FRCs. The highest loads were reported for full bonded FRCs. The significant decrease in the rigidity of spot-bonded FRC splints if compared with full-bonded retainers suggests further tests in order to propose this technique for clinical use, as they allow physiologic tooth movement, thus presumably reducing the risk of ankylosis. PMID:28976936

  18. Spot-Bonding and Full-Bonding Techniques for Fiber Reinforced Composite (FRC and Metallic Retainers

    Directory of Open Access Journals (Sweden)

    Andrea Scribante

    2017-10-01

    Full Text Available Fiber reinforced Composite (FRC retainers have been introduced as an aesthetic alternative to conventional metallic splints, but present high rigidity. The purpose of the present investigation was to evaluate bending and fracture loads of FRC splints bonded with conventional full-coverage of the FRC with a composite compared with an experimental bonding technique with a partial (spot- resin composite cover. Stainless steel rectangular flat, stainless steel round, and FRC retainers were tested at 0.2 and 0.3 mm deflections and at a maximum load. Both at 0.2 and 0.3 mm deflections, the lowest load required to bend the retainer was recorded for spot-bonded stainless steel flat and round wires and for spot-bonded FRCs, and no significant differences were identified among them. Higher force levels were reported for full-bonded metallic flat and round splints and the highest loads were recorded for full-bonded FRCs. At the maximum load, no significant differences were reported among spot- and full-bonded metallic splints and spot-bonded FRCs. The highest loads were reported for full bonded FRCs. The significant decrease in the rigidity of spot-bonded FRC splints if compared with full-bonded retainers suggests further tests in order to propose this technique for clinical use, as they allow physiologic tooth movement, thus presumably reducing the risk of ankylosis.

  19. Spot-Bonding and Full-Bonding Techniques for Fiber Reinforced Composite (FRC) and Metallic Retainers.

    Science.gov (United States)

    Scribante, Andrea; Gandini, Paola; Tessera, Paola; Vallittu, Pekka K; Lassila, Lippo; Sfondrini, Maria Francesca

    2017-10-04

    Fiber reinforced Composite (FRC) retainers have been introduced as an aesthetic alternative to conventional metallic splints, but present high rigidity. The purpose of the present investigation was to evaluate bending and fracture loads of FRC splints bonded with conventional full-coverage of the FRC with a composite compared with an experimental bonding technique with a partial (spot-) resin composite cover. Stainless steel rectangular flat, stainless steel round, and FRC retainers were tested at 0.2 and 0.3 mm deflections and at a maximum load. Both at 0.2 and 0.3 mm deflections, the lowest load required to bend the retainer was recorded for spot-bonded stainless steel flat and round wires and for spot-bonded FRCs, and no significant differences were identified among them. Higher force levels were reported for full-bonded metallic flat and round splints and the highest loads were recorded for full-bonded FRCs. At the maximum load, no significant differences were reported among spot- and full-bonded metallic splints and spot-bonded FRCs. The highest loads were reported for full bonded FRCs. The significant decrease in the rigidity of spot-bonded FRC splints if compared with full-bonded retainers suggests further tests in order to propose this technique for clinical use, as they allow physiologic tooth movement, thus presumably reducing the risk of ankylosis.

  20. Analysis of ochratoxin A in dried blood spots - Correlation between venous and finger-prick blood, the influence of hematocrit and spotted volume.

    Science.gov (United States)

    Osteresch, Bernd; Cramer, Benedikt; Humpf, Hans-Ulrich

    2016-05-01

    We report the improvement of a method for the detection of ochratoxin A (OTA) and its thermal degradation product 2'R-ochratoxin A in dried blood spots (DBS) by high performance liquid chromatographic (HPLC) tandem mass spectrometry (MS/MS). The DBS technique was advanced for the analysis of these two compounds in DBS with unknown amounts of blood as well as varying hematocrit values. Furthermore the comparability of venous vs. capillary blood was investigated. Human whole blood samples were spotted, dried, and extracted with a solvent consisting of acetone, acetonitrile and water for analysis by HPLC-MS/MS. Quantification was carried out by stable isotope labelled internal standards. Blood samples of volunteers (n=50) were used to further optimize and simplify the procedure. Ochratoxin A and 2'R-ochratoxin A concentrations found in the entire spots (approx. 100 μL blood) were compared with punched DBS discs of 8.8mm size containing approximately 20 μL blood. As a result the amounts of both toxins in a punched 8.8mm disc correlate well with the entire DBS. Also the use of capillary blood from finger-pricks versus venous blood was evaluated. The analyte levels correlate as well indicating that the less invasive finger-prick sampling gives also reliable results. The influence of hematocrit was investigated in a range of 25-55% according to the hematocrit in the used real blood samples (34-46% hematocrit). However no significant hematocrit effect was observed for the utilized real blood samples. Moreover different blood volumes were spotted and punched as a minimal spot size is usually recommended for accurate analysis. In this experiment finger-prick samples typically consist of about 90 μL blood. Therefore spots of 75, 100 and 125 μL blood were prepared and analyzed. Similar to the hematocrit effect, no considerable influence was observed. Copyright © 2016 Elsevier B.V. All rights reserved.

  1. Rapid mechanisms of DBS in OCD

    NARCIS (Netherlands)

    de Koning, P.P.

    2016-01-01

    Deep brain stimulation (DBS) for therapy-refractory obsessive-compulsive disorder (OCD) patients is capable of improving psychiatric symptoms within seconds to minutes following stimulation initiation. This extraordinary response enticed my interest in exploring the underlying mechanism of DBS for

  2. Feasibility of self-sampled dried blood spot and saliva samples sent by mail in a population-based study.

    Science.gov (United States)

    Sakhi, Amrit Kaur; Bastani, Nasser Ezzatkhah; Ellingjord-Dale, Merete; Gundersen, Thomas Erik; Blomhoff, Rune; Ursin, Giske

    2015-04-11

    In large epidemiological studies it is often challenging to obtain biological samples. Self-sampling by study participants using dried blood spots (DBS) technique has been suggested to overcome this challenge. DBS is a type of biosampling where blood samples are obtained by a finger-prick lancet, blotted and dried on filter paper. However, the feasibility and efficacy of collecting DBS samples from study participants in large-scale epidemiological studies is not known. The aim of the present study was to test the feasibility and response rate of collecting self-sampled DBS and saliva samples in a population-based study of women above 50 years of age. We determined response proportions, number of phone calls to the study center with questions about sampling, and quality of the DBS. We recruited women through a study conducted within the Norwegian Breast Cancer Screening Program. Invitations, instructions and materials were sent to 4,597 women. The data collection took place over a 3 month period in the spring of 2009. Response proportions for the collection of DBS and saliva samples were 71.0% (3,263) and 70.9% (3,258), respectively. We received 312 phone calls (7% of the 4,597 women) with questions regarding sampling. Of the 3,263 individuals that returned DBS cards, 3,038 (93.1%) had been packaged and shipped according to instructions. A total of 3,032 DBS samples were sufficient for at least one biomarker analysis (i.e. 92.9% of DBS samples received by the laboratory). 2,418 (74.1%) of the DBS cards received by the laboratory were filled with blood according to the instructions (i.e. 10 completely filled spots with up to 7 punches per spot for up to 70 separate analyses). To assess the quality of the samples, we selected and measured two biomarkers (carotenoids and vitamin D). The biomarker levels were consistent with previous reports. Collecting self-sampled DBS and saliva samples through the postal services provides a low cost, effective and feasible

  3. Feasibility of self-sampled dried blood spot and saliva samples sent by mail in a population-based study

    International Nuclear Information System (INIS)

    Sakhi, Amrit Kaur; Bastani, Nasser Ezzatkhah; Ellingjord-Dale, Merete; Gundersen, Thomas Erik; Blomhoff, Rune; Ursin, Giske

    2015-01-01

    In large epidemiological studies it is often challenging to obtain biological samples. Self-sampling by study participants using dried blood spots (DBS) technique has been suggested to overcome this challenge. DBS is a type of biosampling where blood samples are obtained by a finger-prick lancet, blotted and dried on filter paper. However, the feasibility and efficacy of collecting DBS samples from study participants in large-scale epidemiological studies is not known. The aim of the present study was to test the feasibility and response rate of collecting self-sampled DBS and saliva samples in a population–based study of women above 50 years of age. We determined response proportions, number of phone calls to the study center with questions about sampling, and quality of the DBS. We recruited women through a study conducted within the Norwegian Breast Cancer Screening Program. Invitations, instructions and materials were sent to 4,597 women. The data collection took place over a 3 month period in the spring of 2009. Response proportions for the collection of DBS and saliva samples were 71.0% (3,263) and 70.9% (3,258), respectively. We received 312 phone calls (7% of the 4,597 women) with questions regarding sampling. Of the 3,263 individuals that returned DBS cards, 3,038 (93.1%) had been packaged and shipped according to instructions. A total of 3,032 DBS samples were sufficient for at least one biomarker analysis (i.e. 92.9% of DBS samples received by the laboratory). 2,418 (74.1%) of the DBS cards received by the laboratory were filled with blood according to the instructions (i.e. 10 completely filled spots with up to 7 punches per spot for up to 70 separate analyses). To assess the quality of the samples, we selected and measured two biomarkers (carotenoids and vitamin D). The biomarker levels were consistent with previous reports. Collecting self-sampled DBS and saliva samples through the postal services provides a low cost, effective and feasible

  4. Disrupting neuronal transmission: Mechanism of DBS?

    Directory of Open Access Journals (Sweden)

    Satomi eChiken

    2014-03-01

    Full Text Available Applying high-frequency stimulation to deep brain rain structure, known as deep brain stimulation (DBS, has now been recognized an effective therapeutic option for a wide range of neurological and psychiatric disorders. DBS targeting the basal ganglia thalamo-cortical loop, especially the internal segment of the globus pallidus, subthalamic nucleus and thalamus, has been widely employed as a successful surgical therapy for movement disorders, such as Parkinson’s disease, dystonia and tremor. However, the neurophysiological mechanism underling the action of DBS remains unclear and is still under debate: does DBS inhibit or excite local neuronal elements? In this review, we will examine this question and propose the alternative interpretation: DBS dissociates inputs and outputs, resulting in disruption of abnormal signal transmission.

  5. D.B.S. in disordered insulators

    International Nuclear Information System (INIS)

    Bunch, J.M.

    1976-01-01

    These studies were undertaken in order to determine insulator properties for the CTR program. Most of the d.b.s. studies so far have been with various forms of Al 2 O 3 . Some work using fission neutrons and 15-MeV protons along with some high-energy heavy ions is briefly described. Attempts to measure d.b.s. and other electrical properties are mentioned

  6. Performance of an app measuring spot quality in dried blood spot sampling

    NARCIS (Netherlands)

    Veenhof, Herman

    2016-01-01

    Introduction: The Dried Blood Spot sampling (DBS) method gives patients and health care workers the opportunity for remote sampling using a drop of blood from a fingerprick on a sampling card which can be send to the laboratory by mail. Laboratory analysts frequently reject DBS samples because of

  7. A Novel, Nondestructive, Dried Blood Spot-Based Hematocrit Prediction Method Using Noncontact Diffuse Reflectance Spectroscopy

    NARCIS (Netherlands)

    Capiau, S.; Wilk, L.S.; Aalders, M.C.G.; Stove, C.P.

    2016-01-01

    Dried blood spot (DBS) sampling is recognized as a valuable alternative sampling strategy both in research and in clinical routine. Although many advantages are associated with DBS sampling, its more widespread use is hampered by several issues, of which the hematocrit effect on DBS-based

  8. Analysis of multiple access techniques in multi-satellite and multi-spot mobile satellite systems

    Science.gov (United States)

    Corazza, Giovanni E.; Ferrarelli, Carlo; Vatalaro, Francesco

    1995-01-01

    In this paper the analysis of mobile satellite systems adopting constellations of multi-spot satellites over non-geostationary orbits is addressed. A link design procedure is outlined, taking into account system spectrum efficiency, probability of bit error and outage probability. A semi-analytic approach to the evaluation of outage probability in the presence of fading and imperfect power control is described, and applied to single channel per carrier (SCPC) and code division multiple access (CDMA) techniques. Some results are shown for the Globalstar, Iridium and Odyssey orbital configurations.

  9. Analysis of benzodiazepines and their metabolites using DBS cards and LC-MS/MS.

    Science.gov (United States)

    Lee, Heesang; Park, Yujin; Jo, Jiyeong; In, Sangwhan; Park, Yonghoon; Kim, Eunmi; Pyo, Jaesung; Choe, Sanggil

    2015-10-01

    Dried Blood Spot (DBS) has been used a blood extraction method for inherited metabolic disorder screening since 1960s. With introduction of LC-MS/MS, not only DBS could be used to analysis drugs in small blood volume, but in various fields, such as toxicology, drug therapeutic monitoring, drug diagnostic screening, and illicit drugs. In toxicology field, many drugs (e.g. benzodiazepines, acetaminophen, small molecule drugs) have been tested with DBS. Compared with earlier blood extraction methods (SPE and LLE), DBS has lots of advantages; lower blood volume (less than 50μL), shorter analysis time caused by a more concise analysis procedure and lower cost. We optimized the DBS procedure and LC-MS/MS conditions for 18 benzodiazepines, seven benzodiazepine metabolites, and one z-drug (zolpidem) analysis in blood. 30μL of whole blood was spotted on FTA DMPK card C and dried for 2h in a desiccator. A 6-mm disk was punched and vortexed for 1min in a centrifuge tube with 300μL methanol/acetonitrile mixture (1:1, v/v). After evaporation, redissolved in 100μL mobile phase of LC-MS/MS and 5μL was injected. In the analysis for 26 target compounds in blood, all of the method validation parameters - LLOD, LLOQ, accuracy (intra- and inter-assay), and precision (intra- and inter-assay) - were satisfied with method validation criteria, within 15%. The results of matrix effect, recovery, and process efficiency were good. We developed a fast and reliable sample preparation method using DBS for 26 benzodiazepines, benzodiazepine metabolites, and z-drug (zolpidem). Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

  10. Evaluation of the nugget diameter in spot welded joints between two steel sheets by means of a potential drop technique

    Science.gov (United States)

    Tohmyoh, Hironori; Ikarashi, Hidetomo; Matsui, Yoichi; Hasegawa, Yuta; Obara, Satoshi

    2015-08-01

    A potential drop technique which utilizes the electrical circuit used in resistance spot welding is reported. Spot welded samples comprising two steel sheets were inserted between the two Cu electrodes and a constant direct current was supplied between the electrodes. The potential drop between two points, one on each electrode, was determined by analysis for various values of nugget diameter and various values of the contact resistance between the Cu electrodes and the steel sheet sample. The nugget diameter of the spot welded joint could be quantitatively evaluated from the measured potential drop and the equation obtained from the analysis.

  11. Genetic screening of spinal muscular atrophy using a real-time modified COP-PCR technique with dried blood-spot DNA.

    Science.gov (United States)

    Ar Rochmah, Mawaddah; Harahap, Nur Imma Fatimah; Niba, Emma Tabe Eko; Nakanishi, Kenta; Awano, Hiroyuki; Morioka, Ichiro; Iijima, Kazumoto; Saito, Toshio; Saito, Kayoko; Lai, Poh San; Takeshima, Yasuhiro; Takeuchi, Atsuko; Bouike, Yoshihiro; Okamoto, Maya; Nishio, Hisahide; Shinohara, Masakazu

    2017-10-01

    Spinal muscular atrophy (SMA) is a common neuromuscular disorder caused by mutations in SMN1. More than 95% of SMA patients carry homozygous SMN1 deletion. SMA is the leading genetic cause of infant death, and has been considered an incurable disease. However, a recent clinical trial with an antisense oligonucleotide drug has shown encouraging clinical efficacy. Thus, early and accurate detection of SMN1 deletion may improve prognosis of many infantile SMA patients. A total of 88 DNA samples (37 SMA patients, 12 carriers and 39 controls) from dried blood spots (DBS) on filter paper were analyzed. All participants had previously been screened for SMN genes by PCR restriction fragment length polymorphism (PCR-RFLP) using DNA extracted from freshly collected blood. DNA was extracted from DBS that had been stored at room temperature (20-25°C) for 1week to 5years. To ensure sufficient quality and quantity of DNA samples, target sequences were pre-amplified by conventional PCR. Real-time modified competitive oligonucleotide priming-PCR (mCOP-PCR) with the pre-amplified PCR products was performed for the gene-specific amplification of SMN1 and SMN2 exon 7. Compared with PCR-RFLP using DNA from freshly collected blood, results from real-time mCOP-PCR using DBS-DNA for detection of SMN1 exon 7 deletion showed a sensitivity of 1.00 (CI [0.87, 1.00])] and specificity of 1.00 (CI [0.90, 1.00]), respectively. We combined DNA extraction from DBS on filter paper, pre-amplification of target DNA, and real-time mCOP-PCR to specifically detect SMN1 and SMN2 genes, thereby establishing a rapid, accurate, and high-throughput system for detecting SMN1-deletion with practical applications for newborn screening. Copyright © 2017 The Japanese Society of Child Neurology. Published by Elsevier B.V. All rights reserved.

  12. Evaluation of a novel dried blood spot collection device (HemaSpot™) to test blood samples collected from dogs for antibodies to Leishmania infantum.

    Science.gov (United States)

    Rosypal, Alexa C; Pick, Leanne D; Hernandez, Jaime O Esquivel; Lindsay, David S

    2014-09-15

    Collection of blood samples from veterinary and wildlife patients is often challenging because the samples have to be collected on farm or in the wild under various environmental conditions. This poses many technical problems associated with venipuncture materials, their safe use and disposal, transportation and processing of collected samples. Dried blood spot (DBS) sample collection techniques offer a simple and practical alternative to traditional blood collection methods to obtain blood samples from animals for parasite antibody evaluation. The DBS collection devices are compact, simple to use, and are particularly useful for large number of samples. Additionally, DBS samples take up less space and they are easier to transport than traditional venipuncture-collected blood samples. Visceral leishmaniasis (VL) is a potentially fatal parasitic disease of dogs and humans and it is frequently diagnosed by antibody tests. Immunochromatographic tests (ICT) for antibodies to Leishmania infantum are commercially available for dogs and they produce qualitative results in minutes. Measurement of canine antibodies to L. infantum with the ICT using traditional venipuncture has been validated previously, but the use of DBS samples has not been evaluated using this method. The purpose of the present study was to determine the ability of DBS samples to detect antibodies to L. infantum in dogs using a commercial ICT assay. One hundred plasma samples from dogs experimentally infected with the LIVT-1 strain of L. infantum were collected by venipuncture and frozen. Individual samples were thawed, and then 80 μl plasma (2 drops) was aliquotted onto the 8-spoked disk pad on individual DBS sample collection devices (HemaSpot™, Spot-On Sciences, Austin, TX), dried, and stored in the dark at room temperature. After one month and six months, respectively, 2 spokes of the 8 spokes of the disk pad of each DBS sample were removed and eluted in 200 μl PBS. The eluate was used to test

  13. Experimental determination of liquidus of Fe-Zr by spot technique

    International Nuclear Information System (INIS)

    Ramakrishna, P.; Samanta, B.; Balakrishnan, S.

    2016-01-01

    Metallic fuel alloy for fast reactor mainly consist of U-Pu-Zr housed in T91 clad. Study of thermophysical properties of fuel element and cladding material is vital for the fuel designer to optimize the design feature and predict the fuel behavior under reactor operating conditions.To understand the fuel-clad interaction the phase diagram study of Fe-Zr system is very important since future reactors use U-Pu-Zr alloy as fuel and stainless steel as clad. The eutectic temperature in Fe-Zr alloy system has been established experimentally by various methods. Information on the liquidus temperatures of Fe-Zr is scanty in the literature excepting a very few experimental measurements. Hence measurement of liquidus temperatures is very essential to establish the phase diagram. Present work concentrates more on the generation of liquidus data of Fe-Zr binary alloy system by Spot-technique. This is one among the advanced techniques for measuring the solid-liquid phase transition temperatures. (author)

  14. Dried Blood Spots Combined With Ultra-High-Performance Liquid Chromatography-Mass Spectrometry for the Quantification of the Antipsychotics Risperidone, Aripiprazole, Pipamperone, and Their Major Metabolites.

    Science.gov (United States)

    Tron, Camille; Kloosterboer, Sanne M; van der Nagel, Bart C H; Wijma, Rixt A; Dierckx, Bram; Dieleman, Gwen C; van Gelder, Teun; Koch, Birgit C P

    2017-08-01

    Risperidone, aripiprazole, and pipamperone are antipsychotic drugs frequently prescribed for the treatment of comorbid behavioral problems in children with autism spectrum disorders. Therapeutic drug monitoring (TDM) could be useful to decrease side effects and to improve patient outcome. Dried blood spot (DBS) sample collection seems to be an attractive technique to develop TDM of these drugs in a pediatric population. The aim of this work was to develop and validate a DBS assay suitable for TDM and home sampling. Risperidone, 9-OH risperidone, aripiprazole, dehydroaripiprazole, and pipamperone were extracted from DBS and analyzed by ultra-high-performance liquid chromatography-tandem mass spectrometry using a C18 reversed-phase column with a mobile phase consisting of ammonium acetate/formic acid in water or methanol. The suitability of DBS for TDM was assessed by studying the influence of specific parameters: extraction solution, EDTA carryover, hematocrit, punching location, spot volume, and hemolysis. The assay was validated with respect to conventional guidelines for bioanalytical methods. The method was linear, specific without any critical matrix effect, and with a mean recovery around 90%. Accuracy and imprecision were within the acceptance criteria in samples with hematocrit values from 30% to 45%. EDTA or hemolysis did not skew the results, and no punching carryover was observed. No significant influence of the spot volume or the punch location was observed. The antipsychotics were all stable in DBS stored 10 days at room temperature and 1 month at 4 or -80°C. The method was successfully applied to quantify the 3 antipsychotics and their metabolites in patient samples. A UHPLC-MS/MS method has been successfully validated for the simultaneous quantification of risperidone, 9-OH risperidone, aripiprazole, dehydroaripiprazole, and pipamperone in DBS. The assay provided good analytical performances for TDM and clinical research applications.

  15. Whole genome sequencing of Plasmodium falciparum from dried blood spots using selective whole genome amplification.

    Science.gov (United States)

    Oyola, Samuel O; Ariani, Cristina V; Hamilton, William L; Kekre, Mihir; Amenga-Etego, Lucas N; Ghansah, Anita; Rutledge, Gavin G; Redmond, Seth; Manske, Magnus; Jyothi, Dushyanth; Jacob, Chris G; Otto, Thomas D; Rockett, Kirk; Newbold, Chris I; Berriman, Matthew; Kwiatkowski, Dominic P

    2016-12-20

    Translating genomic technologies into healthcare applications for the malaria parasite Plasmodium falciparum has been limited by the technical and logistical difficulties of obtaining high quality clinical samples from the field. Sampling by dried blood spot (DBS) finger-pricks can be performed safely and efficiently with minimal resource and storage requirements compared with venous blood (VB). Here, the use of selective whole genome amplification (sWGA) to sequence the P. falciparum genome from clinical DBS samples was evaluated, and the results compared with current methods that use leucodepleted VB. Parasite DNA with high (>95%) human DNA contamination was selectively amplified by Phi29 polymerase using short oligonucleotide probes of 8-12 mers as primers. These primers were selected on the basis of their differential frequency of binding the desired (P. falciparum DNA) and contaminating (human) genomes. Using sWGA method, clinical samples from 156 malaria patients, including 120 paired samples for head-to-head comparison of DBS and leucodepleted VB were sequenced. Greater than 18-fold enrichment of P. falciparum DNA was achieved from DBS extracts. The parasitaemia threshold to achieve >5× coverage for 50% of the genome was 0.03% (40 parasites per 200 white blood cells). Over 99% SNP concordance between VB and DBS samples was achieved after excluding missing calls. The sWGA methods described here provide a reliable and scalable way of generating P. falciparum genome sequence data from DBS samples. The current data indicate that it will be possible to get good quality sequence on most if not all drug resistance loci from the majority of symptomatic malaria patients. This technique overcomes a major limiting factor in P. falciparum genome sequencing from field samples, and paves the way for large-scale epidemiological applications.

  16. Analysis of blood spots for polyfluoroalkyl chemicals

    Energy Technology Data Exchange (ETDEWEB)

    Kato, Kayoko; Wanigatunga, Amal A.; Needham, Larry L. [Division of Laboratory Sciences, National Center for Environmental Health, Centers for Disease Control and Prevention, Atlanta, GA (United States); Calafat, Antonia M., E-mail: acalafat@cdc.gov [Division of Laboratory Sciences, National Center for Environmental Health, Centers for Disease Control and Prevention, Atlanta, GA (United States)

    2009-12-10

    Polyfluoroalkyl chemicals (PFCs) have been detected in humans, in the environment, and in ecosystems around the world. The potential for developmental and reproductive toxicities of some PFCs is of concern especially to children's health. In the United States, a sample of a baby's blood, called a 'dried blood spot' (DBS), is obtained from a heel stick within 48 h of a child's birth. DBS could be useful for assessing prenatal exposure to PFCs. We developed a method based on online solid phase extraction coupled with high performance liquid chromatography-isotope dilution tandem mass spectrometry for measuring four PFCs in DBS, perfluorooctane sulfonate (PFOS), perfluorohexane sulfonate, perfluorooctanoate (PFOA), and perfluorononanoate. The analytical limits of detection using one whole DBS ({approx}75 {mu}L of blood) were <0.5 ng mL{sup -1}. To validate the method, we analyzed 98 DBS collected in May 2007 in the United States. PFOS and PFOA were detected in all DBS at concentrations in the low ng mL{sup -1} range. These data suggest that DBS may be a suitable matrix for assessing perinatal exposure to PFCs, but additional information related to sampling and specimen storage is needed to demonstrate the utility of these measures for assessing exposure.

  17. DBS in Treatment of Post-Traumatic Stress Disorder

    Directory of Open Access Journals (Sweden)

    Angelo Lavano

    2018-01-01

    Full Text Available Post-traumatic stress disorder (PTSD is a debilitating psychiatric condition for which pharmacological therapy is not always solvable. Various treatments have been suggested and deep brain stimulation (DBS is currently under investigation for patients affected by PTSD. We review the neurocircuitry and up-to-date clinical concepts which are behind the use of DBS in posttraumatic stress disorder (PTSD. The role of DBS in treatment-refractory PTSD patients has been investigated relying on both preclinical and clinical studies. DBS for PTSD is in its preliminary phases and likely to provide hope for patients with medical refractory PTSD following the results of randomized controlled studies.

  18. An Inter-Comparison Study of Multi- and DBS Lidar Measurements in Complex Terrain

    Directory of Open Access Journals (Sweden)

    Lukas Pauscher

    2016-09-01

    Full Text Available Wind measurements using classical profiling lidars suffer from systematic measurement errors in complex terrain. Moreover, their ability to measure turbulence quantities is unsatisfactory for wind-energy applications. This paper presents results from a measurement campaign during which multiple WindScanners were focused on one point next to a reference mast in complex terrain. This multi-lidar (ML technique is also compared to a profiling lidar using the Doppler beam swinging (DBS method. First- and second-order statistics of the radial wind velocities from the individual instruments and the horizontal wind components of several ML combinations are analysed in comparison to sonic anemometry and DBS measurements. The results for the wind speed show significantly reduced scatter and directional error for the ML method in comparison to the DBS lidar. The analysis of the second-order statistics also reveals a significantly better correlation for the ML technique than for the DBS lidar, when compared to the sonic. However, the probe volume averaging of the lidars leads to an attenuation of the turbulence at high wave numbers. Also the configuration (i.e., angles of the WindScanners in the ML method seems to be more important for turbulence measurements. In summary, the results clearly show the advantages of the ML technique in complex terrain and indicate that it has the potential to achieve significantly higher accuracy in measuring turbulence quantities for wind-energy applications than classical profiling lidars.

  19. Microstructure and mechanical properties of dissimilar Al alloy/steel joints prepared by a flat spot friction stir welding technique

    International Nuclear Information System (INIS)

    Sun, Y.F.; Fujii, H.; Takaki, N.; Okitsu, Y.

    2013-01-01

    Highlights: ► Dissimilar Al/Fe joint was obtained by flat spot friction stir welding technique. ► The surface of the sound Al/Fe joint is smooth without any internal defects. ► No intermetallic compound layer but amorphous area is formed at the weld interface. ► The sound Al/Fe welds show high shear tensile load and fracture through plug mode. ► The probe length exerts little effect on the welds’ microstructure and properties. - Abstract: The 6061-T6 Al alloy and mild steel plate with a thickness of 1 mm were successfully welded by the flat spot friction stir welding technique, which contains two steps during the entire welding process. The rotating tools with different probe lengths of 1.0, 1.3 and 1.5 mm were used in the first step, during which a conventional spot FSW was conducted above a round dent previously made on the back plate. However, sound Al/Fe welds with similar microstructure and mechanical properties can still be obtained after the second step, during which a probe-less rotating tool was used to flatten the weld surface. The sound welds have smooth surface without keyholes and other internal welding defects. No intermetallic compound layer but some areas with amorphous atomic configuration was formed along the Al/Fe joint interface due to the lower heat input. The shear tensile failure load can reach a maximum value of 3607 N and fracture through plug mode. The probe length has little effect on the weld properties, which indicates that the tool life can be significantly extended by this new spot welding technique

  20. Four spot laser anemometer and optical access techniques for turbine applications

    Science.gov (United States)

    Wernet, Mark P.

    1987-01-01

    A time-of-flight anemometer (TOFA) system utilizing a spatial lead-lag filter for bipolar pulse generation has been constructed and tested. This system, called a four-spot laser anemometer, was specifically designed for use in high-speed, turbulent flows in the presence of walls or surfaces. The TOFA system uses elliptical spots to increase the flow acceptance angle to be comparable with that of a fringe-type anemometer. The tightly focused spots used in the four spot yield excellent flare light rejection capabilities. Good results have been obtained to 75 microns normal to a surface, with an f/2.5 collection lens. This system is being evaluated for use in a warm turbine facility. Results from both a particle-lag velocity experiment and boundary layer profiles will be discussed. In addition, an analysis of the use of curved windows in a turbine casing will be presented. Curved windows, matching the inner radius of the turbine casing, preserve the flow conditions, but introduce astigmatic aberrations. A correction optic was designed that virtually eliminates these astigmatic aberrations throughout the intrablade survey region for normal incidence.

  1. Parkinson’s disease DBS: what, when, who and why? The time has come to tailor DBS targets.

    Science.gov (United States)

    Okun, Michael S; Foote, Kelly D

    2010-12-01

    Deep brain stimulation (DBS) has recently been proven to be an effective therapy for medication refractory symptoms of Parkinson's disease. As the evidence base continues to evolve, many important issues have surfaced, including: what operation should be performed (brain target[s],unilateral vs bilateral, simultaneous vs staged); when to operate (how early is too early to intervene?), who should be operated on (disease duration, age, symptom profiles and the use of the interdisciplinary screening team); and finally, why to operate (the rationale of surgery vs medication/apomorphine pumps/duodopa pumps/stem cell trials/gene therapy trials). We will address each of these critical issues, as well make the argument that a tailored approach to DBS and DBS targeting will best serve each potential candidate. We will review the multiple peer reviewed studies and we will emphasize the recently available data from randomized DBS studies.We will argue that moving away from a single DBS target (e.g., subthalamic nucleus DBS) and a single approach to DBS methodology (e.g., bilateral simultaneous operations) is a reasonable next step for the Parkinson's disease community. Following careful interdisciplinary DBS screening, a physician-patient discussion has the potential to establish a patient-centered and symptom-specific outcome for each potential DBS candidate. The interdisciplinary DBS team can function together to formulate and to consider an optimal and tailored approach. A tailored approach will allow for the consideration of the complex and numerous variables that may contribute to a positive or negative overall DBS outcome. We will review and provide expert commentary on a potential interdisciplinary approach to selecting unilateral or alternatively bilateral subthalamic nucleus or globus pallidus internus DBS. Our approach is aimed to maximize benefit(s) and minimize risk(s) in order to best tailor therapy for an individual patient.

  2. Validation and Application of a Dried Blood Spot Ceftriaxone Assay.

    Science.gov (United States)

    Page-Sharp, Madhu; Nunn, Troy; Salman, Sam; Moore, Brioni R; Batty, Kevin T; Davis, Timothy M E; Manning, Laurens

    2015-10-05

    Dried blood spot (DBS) antibiotic assays can facilitate pharmacokinetic/pharmacodynamic (PK/PD) studies in situations where venous blood sampling is logistically and/or ethically problematic. In this study, we aimed to develop, validate, and apply a DBS ceftriaxone assay. A liquid chromatography-tandem mass spectroscopy (LC-MS/MS) DBS ceftriaxone assay was assessed for matrix effects, process efficiency, recovery, variability, and limits of quantification (LOQ) and detection (LOD). The effects of hematocrit, protein binding, red cell partitioning, and chad positioning were evaluated, and thermal stability was assessed. Plasma, DBS, and cell pellet ceftriaxone concentrations in 10 healthy adults were compared, and plasma concentration-time profiles of DBS and plasma ceftriaxone were incorporated into population PK models. The LOQ and LOD for ceftriaxone in DBS were 0.14 mg/liter and 0.05 mg/liter, respectively. Adjusting for hematocrit, red cell partitioning, and relative recovery, DBS-predicted plasma concentrations were comparable to measured plasma concentrations (r > 0.95, P ceftriaxone retained >95% initial concentrations in DBS for 14 h, 35 h, 30 days, 21 weeks, and >11 months, respectively. The present DBS ceftriaxone assay is robust and can be used as a surrogate for plasma concentrations to provide valid PK and PK/PD data in a variety of clinical situations, including in studies of young children and of those in remote or resource-poor settings. Copyright © 2015, American Society for Microbiology. All Rights Reserved.

  3. A modified low-temperature wafer bonding method using spot pressing bonding technique and water glass adhesive layer

    Science.gov (United States)

    Xu, Yang; Wang, Shengkai; Wang, Yinghui; Chen, Dapeng

    2018-02-01

    A modified low-temperature wafer bonding method using a spot pressing bonding technique and a water glass adhesive layer is proposed. The electrical properties of the water glass layer has been studied by capacitance–voltage (C–V) and electric current–voltage (I–V) measurements. It is found that the adhesive layer can be regarded as a good insulator in terms of leakage current density. The bonding mechanism and the motion of bubbles during the thermal treatment are investigated. The dominant factor for the bubble motion in the modified bonding process is the gradient of pressure introduced by the spot pressing force. It is proved that the modified method achieves low-temperature adhesive bonding, minimizes the effect of water desorption, and provides good bonding performance.

  4. Effect of caries infiltration technique and fluoride therapy on the colour masking of white spot lesions.

    Science.gov (United States)

    Rocha Gomes Torres, Carlos; Borges, Alessandra Buhler; Torres, Luciana Marcondes Sarmento; Gomes, Isabela Silva; de Oliveira, Rodrigo Simões

    2011-03-01

    A carious lesion is initiated through the subsurface demineralization of enamel, and presents clinically as a white spot, interfering with the aesthetics. This lesion should not receive restorative treatment because it is capable of remineralization. The aim of this study was to evaluate the performance of different treatments on masking white spot lesions by assessing the colour change. Artificial white spot lesions were produced in bovine enamel of 60 cylindrical-shaped samples. The samples were randomly divided into four groups: CON (control) - immersion in artificial saliva; DF - daily application of 0.05% fluoride solution; WF - weekly application of 2% fluoride gel; and IC - resin infiltration (Icon(®) - DMG). The assessment of colour was performed by a spectrophotometer in four distinct stages: baseline, after the production of artificial caries; after 4 weeks; after 8 weeks; and after a new acid challenge. The ΔL values were calculated at each stage in relation to the baseline colour. The application of RM ANOVA revealed significant differences between the factors' treatment and time (p=0.001). For the interaction between factors there were no significant differences (p=0.27). The Tukey's test (pcolour change. Copyright © 2011. Published by Elsevier Ltd.

  5. Task Balanced Workflow Scheduling Technique considering Task Processing Rate in Spot Market

    Directory of Open Access Journals (Sweden)

    Daeyong Jung

    2014-01-01

    Full Text Available Recently, the cloud computing is a computing paradigm that constitutes an advanced computing environment that evolved from the distributed computing. And the cloud computing provides acquired computing resources in a pay-as-you-go manner. For example, Amazon EC2 offers the Infrastructure-as-a-Service (IaaS instances in three different ways with different price, reliability, and various performances of instances. Our study is based on the environment using spot instances. Spot instances can significantly decrease costs compared to reserved and on-demand instances. However, spot instances give a more unreliable environment than other instances. In this paper, we propose the workflow scheduling scheme that reduces the out-of-bid situation. Consequently, the total task completion time is decreased. The simulation results reveal that, compared to various instance types, our scheme achieves performance improvements in terms of an average combined metric of 12.76% over workflow scheme without considering the processing rate. However, the cost in our scheme is higher than an instance with low performance and is lower than an instance with high performance.

  6. Intraoperative MR-guided DBS implantation for treating PD and ET

    Science.gov (United States)

    Liu, Haiying; Maxwell, Robert E.; Truwit, Charles L.

    2001-05-01

    Deep brain stimulator (DBS) implantation is a promising treatment alternative for suppressing the motor tremor symptoms in Parkinson disease (PD) patient. The main objective is to develop a minimally invasive approach using high spatial resolution and soft-tissue contrast MR imaging techniques to guide the surgical placement of DBS. In the MR-guided procedure, the high spatial resolution MR images were obtained intra-operatively and used to target stereotactically a specific deep brain location. The neurosurgery for craniotomy was performed in the front of the magnet outside of the 10 Gauss line. Aided with positional registration assembly for the stereotactic head frame, the target location (VIM or GPi or STN) in deep brain areas was identified and measured from the MR images in reference to the markers in the calibration assembly of the head frame before the burrhole prep. In 20 patients, MR- guided DBS implantations have been performed according to the new methodology. MR-guided DBS implantation at high magnetic field strength has been shown to be feasible and desirable. In addition to the improved outcome, this offers a new surgical approach in which intra-operative visualization is possible during intervention, and any complications such as bleeding can be assessed in situ immediately prior to dural closure.

  7. A Simple Phosphate-Buffered-Saline-Based Extraction Method Improves Specificity of HIV Viral Load Monitoring Using Dried Blood Spots.

    Science.gov (United States)

    Makadzange, A Tariro; Boyd, F Kathryn; Chimukangara, Benjamin; Masimirembwa, Collen; Katzenstein, David; Ndhlovu, Chiratidzo E

    2017-07-01

    Although Roche COBAS Ampliprep/COBAS TaqMan (CAP/CTM) systems are widely used in sub-Saharan Africa for early infant diagnosis of HIV from dried blood spots (DBS), viral load monitoring with this system is not practical due to nonspecific extraction of both cell-free and cell-associated viral nucleic acids. A simplified DBS extraction technique for cell-free virus elution using phosphate-buffered saline (PBS) may provide an alternative analyte for lower-cost quantitative HIV virus load (VL) testing to monitor antiretroviral therapy (ART). We evaluated the CAP/CTM v2.0 assay in 272 paired plasma and DBS specimens using the cell-free virus elution method and determined the level of agreement, sensitivity, and specificity at thresholds of target not detected (TND), target below the limit of quantification (BLQ) (1,000 copies/ml, the sensitivities, specificities, positive predictive values (PPV), and negative predictive values (NPV) were 92.7%, 100%, 100%, and 94.3%, respectively. PBS elution of DBS offers a sensitive and specific method for monitoring plasma viremia among adults and children on ART at the WHO-recommended threshold of >1,000 copies/ml on the Roche CAP/CTM system. Copyright © 2017 Makadzange et al.

  8. Quantification of multiple elements in dried blood spot samples

    DEFF Research Database (Denmark)

    Pedersen, Lise; Andersen-Ranberg, Karen; Hollergaard, Mads

    2017-01-01

    in venous blood. Samples with different hematocrit were spotted onto filter paper to assess hematocrit effect. RESULTS: The established method was precise and accurate for measurement of most elements in DBS. There was a significant but relatively weak correlation between measurement of the elements Mg, K......BACKGROUND: Dried blood spots (DBS) is a unique matrix that offers advantages compared to conventional blood collection making it increasingly popular in large population studies. We here describe development and validation of a method to determine multiple elements in DBS. METHODS: Elements were...... extracted from punches and analyzed using inductively coupled plasma-mass spectrometry (ICP-MS). The method was evaluated with quality controls with defined element concentration and blood spiked with elements to assess accuracy and imprecision. DBS element concentrations were compared with concentrations...

  9. Current technology and techniques in re-mineralization of white spot lesions: A systematic review

    Science.gov (United States)

    Podray, Susan S.

    White Spot lesions are a common iatrogenic occurrence on patients who are treated with fixed orthodontic appliances. There is a dynamic chemical interaction between enamel and saliva at the tooth surface that allow a lesion to have phase changes involving demineralization of enamel and reminerlization. This is due to calcium and phosphate dissolved in saliva that is deposited onto the tooth surface or removed depending on the surrounding pH. Caseinphosphopeptide-amorphous calcium phosphate (CPP-ACP) is gaining popularity in dentistry as a way to increase the available level of calcium and phosphate in plaque and saliva to improve the chemical gradient so that if favors reminerlization. The aim of our investigation is to search the available current literature and formulate a recommendation for use of CPP-ACP in orthodontics. Publications from the following electronic databases were searched: PubMed, Web of Science, Cochrane Library and Science Direct. Searches from August 2010 to April 1st 2012 were performed under the terms "MI Paste OR Recaldent OR caseinphosphopeptide-amorphous calcium phosphate OR CPP-ACP or tooth mousse". The searches yielded 155 articles, These were reviewed for relevance based on inclusion and exclusion criteria. Articles with inappropriate study design or no outcome measures at both baseline and end point were also excluded. 13 articles were deemed of relevance with a high quality study design and were included in this study for evaluation. The current literature suggests a preventative treatment regimen in which MI Paste Plus is used. It should be delivered once daily prior to bed after oral hygiene for 3 minutes in a fluoride tray, throughout orthodontic treatment. It should be recommended for high risk patients determined by poor oral hygiene, as seen by the inability to remove plaque from teeth and appliances. This protocol may prevent or assist in the remineralization of enamel white spot lesions during and after orthodontic treatment.

  10. An Inter-Comparison Study of Multi- and DBS Lidar Measurements in Complex Terrain

    DEFF Research Database (Denmark)

    Pauscher, Lukas; Vasiljevic, Nikola; Callies, Doron

    2016-01-01

    Wind measurements using classical profiling lidars suffer from systematic measurement errors in complex terrain. Moreover, their ability to measure turbulence quantities is unsatisfactory for wind-energy applications. This paper presents results from a measurement campaign during which multiple...... WindScanners were focused on one point next to a reference mast in complex terrain. This multi-lidar (ML) technique is also compared to a profiling lidar using the Doppler beam swinging (DBS) method. First- and second-order statistics of the radial wind velocities from the individual instruments...... reveals a significantly better correlation for the ML technique than for the DBS lidar, when compared to the sonic. However, the probe volume averaging of the lidars leads to an attenuation of the turbulence at high wave numbers. Also the configuration (i.e., angles) of the WindScanners in the ML method...

  11. The use of dried blood spots for quantification of 15 antipsychotics and 7 metabolites with ultra-high performance liquid chromatography - tandem mass spectrometry.

    Science.gov (United States)

    Patteet, Lisbeth; Maudens, Kristof E; Stove, Christophe P; Lambert, Willy E; Morrens, Manuel; Sabbe, Bernard; Neels, Hugo

    2015-06-01

    Therapeutic drug monitoring of antipsychotics is important in optimizing individual therapy. In psychiatric populations, classical venous blood sampling is experienced as frightening. Interest in alternative techniques, like dried blood spots (DBS), has consequently increased. A fast and easy to perform DBS method for quantification of 16 antipsychotics (amisulpride, aripiprazole, asenapine, bromperidol, clozapine, haloperidol, iloperidone, levosulpiride, lurasidone, olanzapine, paliperidone, pipamperone, quetiapine, risperidone, sertindole and zuclopenthixol) and 8 metabolites was developed. DBS were prepared using 25 μL of whole blood and extraction of complete spots was performed using methanol: methyl-t-butyl-ether (4:1). After evaporation, the extract was reconstituted in the mobile phase and 10 μL were injected on an ultra-high performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS). Separation using a C18 column and gradient elution with a flow rate of 0.5 mL/min resulted in a 6-min run-time. Ionization was performed in positive mode and a dynamic MRM method was applied. Median recovery was 66.4 % (range 28.7-84.5%). Accuracy was within the acceptance criteria, except for pipamperone (LLOQ and low concentration) and lurasidone (low concentration). Imprecision was only aberrant for lurasidone at low and medium concentration. All compounds were stable during 1 month at room temperature, 4 °C and -18 °C. Lurasidone was unstable when the extract was stored for 12 h on the autosampler. Absolute matrix effects (ME) (median 66.1%) were compensated by the use of deuterated IS (median 98.8%). The DBS method was successfully applied on 25-μL capillary DBS from patients and proved to be a reliable alternative for quantification of all antipsychotics except for olanzapine and N-desmethylolanzapine. Copyright © 2014 John Wiley & Sons, Ltd.

  12. Othello syndrome after STN DBS - psychiatric side-effects of DBS and methods of dealing with them.

    Science.gov (United States)

    Antosik-Wójcińska, Anna Zofia; Święcicki, Łukasz; Bieńkowski, Przemysław; Mandat, Tomasz; Sołtan, Emilia

    Deep brain stimulation is a therapeutic method used for decades in neurological diseases such as Parkinson's disease or dystonia. Despite many publications concerning DBS, there are few publications on psychotic symptoms after DBS, there are also no standards of dealing with them. The authors present a case of a patient with Parkinson's disease, in whom psychotic symptoms in the form of Othello-like syndrome appeared after implantation of a stimulator. In this case the strategy of continuation of stimulation and adding antipsychotic drug (quetiapine) was chosen. Gradual resolution of psychotic symptoms, without worsening of neurological symptoms and no recurrence of psychiatric symptoms was observed. In recent years, work is underway on the use of DBS in psychiatry, particularly in patients with treatment-resistant depression. It is necessary to set the strategy for dealing with side-effects of DBS. Most of the authors prefer the temporary or permanent switch off the stimulator. In the author's opinion, in some cases it is possible to effectively treat the psychotic symptoms without resignation from the benefits of stimulation. So far, however, such cases were described so rarely that it is difficult on this basis to formulate conclusions that can be applied to the whole population of patients treated with DBS. Only a systematic study including an assessment of psychotic symptoms using scales and analysing the received treatment and stimulation parameters could give an idea of what is the most appropriate strategy in case of psychosis following DBS.

  13. Governing biological material at the intersection of care and research: the use of dried blood spots for biobanking

    NARCIS (Netherlands)

    Douglas, C.M.W.; van El, C.G.; Faulkner, A.; Cornel, M.C.

    2012-01-01

    A series of governance issues currently surrounds the multiple uses and multiple users of dried blood spots (DBS) for research purposes. Internationally there is a discussion on storing DBS resulting from newborn screening for public health and using them as the basis for large biobanklike

  14. Dried blood spot validation of five immunosuppressants, without hematocrit correction, on two LC-MS/MS systems

    NARCIS (Netherlands)

    Koster, Remco A; Veenhof, Herman; Botma, Rixt; Hoekstra, Alle Tjipke; Berger, Stefan P; Bakker, Stephan JL; Alffenaar, Jan-Willem C; Touw, Daan J

    2017-01-01

    AIM: Hematocrit (Ht) effects remain a challenge in dried blood spot (DBS) sampling. The aim was to develop an immunosuppressant DBS assay on two LC-MS/MS systems covering a clinically relevant Ht range without Ht correction. RESULTS: The method was partially validated for tacrolimus, sirolimus,

  15. Three finger palpation technique of vas deferens for keyhole vasectomy in spotted (Axis axis and sambar deer (Cervus unicolor

    Directory of Open Access Journals (Sweden)

    B. J. William

    2014-09-01

    Full Text Available Aim: Vasectomy is performed in deer for population control, maintain pedigreed animals and prevent inbreeding. Conventional procedure of vasectomy required a long-term anesthesia and longer duration of hospitalization, which often result in stress, morbidity and mortality. A study was conducted to capture, neuter and release the deer with minimal hospitalization and stress by adopting three finger palpation technique of vas deferens and performing vasectomy through a key-hole incision. Materials and Methods: The study was conducted on three spotted male deer and three sambar male deer, which were immobilized with a mixture of xylazine at the dose of 1.00 mg/kg and ketamine at the dose of 5.00 mg/kg. The vas deferens could be palpated as a piece of cooked spaghetti at the neck of the scrotum on the anterior aspect by three finger palpation technique and was able to fix the vas deferens between the thumb and middle finger. Through a key-hole incision of <5 mm length, the vas deferens was exteriorized and resected using electrocautery and the skin incision was sealed with methyl methacrylate. The deer were released on the same day, and no post-operative complication was noticed. Conclusion: The study revealed that three finger palpation technique of vas deferens provided guidance for easy access to vas deferens for vasectomy in deer with less hospitalization, and the deer could be released on the same day.

  16. Development and optimization of an internally controlled dried blood spot assay for surveillance of human immunodeficiency virus type-1 drug resistance.

    Science.gov (United States)

    Buckton, Andrew J; Bissett, Sara L; Myers, Richard E; Beddows, Simon; Edwards, Simon; Cane, Patricia A; Pillay, Deenan

    2008-12-01

    We present the evaluation of a methodology for the genotypic assessment of human immunodeficiency virus type-1 (HIV-1) drug resistance, optimized for use with dried blood spots (DBS). The ability to generate HIV-1 protease (PR) and reverse transcriptase (RT) contiguous amplicons and nucleotide sequences from DBS was evaluated. Different collection matrices and extraction methodologies were compared. The relative subtype sensitivity of the amplification strategy was assessed using a comprehensive panel of plasmids representing A-H subtypes. A panel of DBS and plasma specimens was subjected to HIV genotyping. Sequences generated from each sample type were compared. Extensive replicate testing revealed most sensitivity with the use of 903 filter paper and silica/guanidine extraction, which had an estimated 95% inclusivity endpoint of 1542 proviral copies/mL, as compared with 21 573 proviral copies/mL for the FTA system. All HIV-1 group M subtypes analysed-with the exception of subtypes A2, AE, AG, F and H-had a relative sensitivity of /=1000 copies/mL were successfully amplified and sequenced. Twelve specimens had pol genotyping from both plasma and DBS samples. Sequence analysis and drug resistance interpretation revealed that 10 (83%) provided concordant drug resistance interpretation. Our results demonstrate that the technique is appropriate for surveillance of drug resistance in untreated individuals and those with virological failure on therapy.

  17. Food consumption and digestion time estimation of spotted scat, Scatophagus argus, using X-radiography technique

    Science.gov (United States)

    Hashim, Marina; Abidin, Diana Atiqah Zainal; Das, Simon K.; Ghaffar, Mazlan Abd.

    2014-09-01

    The present study was conducted to investigate the food consumption pattern and gastric emptying time using x-radiography technique in scats fish, Scatophagus argus feeding to satiation in laboratory conditions. Prior to feeding experiment, fish of various sizes were examined their stomach volume, using freshly prepared stomachs ligatured at the tips of the burret, where the maximum amount of distilled water collected in the stomach were measured (ml). Stomach volume is correlated with maximum food intake (Smax) and it can estimate the maximum stomach distension by allometric model i.e volume=0.0000089W2.93. Gastric emptying time was estimated using a qualitative X-radiography technique, where the fish of various sizes were fed to satiation at different time since feeding. All the experimental fish was feed into satiation using radio-opaque barium sulphate (BaSO4) paste injected in the wet shrimp in proportion to the body weight. The BaSO4 was found suitable to track the movement of feed/prey in the stomach over time and gastric emptying time of scats fish can be estimated. The results of qualitative X-Radiography observation of gastric motility, showed the fish (200 gm) that fed to maximum satiation meal (circa 11 gm) completely emptied their stomach within 30 - 36 hrs. The results of the present study will provide the first baseline information on the stomach volume, gastric emptying of scats fish in captivity.

  18. Evaluation of the human immunodeficiency virus type 1 and 2 antibodies detection in dried whole blood spots (dbs samples Pesquisa de anticorpos contra o vírus da imunodeficiência humana tipos 1 e 2 em amostras de sangue seco coletadas em papel filtro

    Directory of Open Access Journals (Sweden)

    Andréa Cauduro de Castro

    2008-06-01

    Full Text Available Human Immunodeficiency Vírus Type 1 and 2 antibodies detection was performed in 457 dried whole blood spots samples (S&S 903. Q-Preven HIV 1+2 was the screening test used. The results were compared with the gold standard serum tests by ELISA (Cobas Core e Axsym HIV1/2 gO and imunofluorescence was the definitive confirmatory test. The samples were obtained from the Hospital Nossa Senhora da Conceição in Porto Alegre, RS - Brazil, through whole blood transfer to filter paper card and sent to Caxias do Sul, RS - Brazil where the tests were performed. The dried whole blood spot stability was evaluated with two different panels. The first one was composed of five negative and five positive samples stored at room temperature, 4 ºC, -20 ºC and -70 ºC, while the second was composed of two negative and three positive samples stored at 37 ºC (humidity Foram realizados 457 testes para detectar anticorpos contra o Vírus da Imunodeficiência Humana tipos 1 e 2, em amostras de sangue total seco coletadas em papel filtro (S&S 903, com o teste de triagem Q-Preven HIV 1+2, comparando-se com os resultados dos testes de triagem no soro (Cobas Core e Axsym HIV1/2 gO, sendo a imunofluorescência indireta o teste confirmatório. As amostras foram obtidas no Hospital Conceição em Porto Alegre, pela transferência de sangue total para cartão de papel filtro e encaminhadas para Caxias do Sul para a realização dos testes. Foi analisada a estabilidade da amostra em papel filtro com a utilização de dois painéis: o primeiro com cinco amostras negativas e cinco positivas armazenadas por seis semanas à temperatura ambiente, 4 ºC, -20 ºC e -70 ºC; o segundo com duas negativas e três positivas armazenadas por seis semanas com avaliações semanais a 37 ºC (umidade <50%. Os resultados de todas as amostras testadas foram mantidos. A sensibilidade foi de 100%, a especificidade de 99,6%, o valor preditivo positivo de 99,5% e o valor preditivo negativo de 100

  19. Medical image of the week: DBS polysomnogram artifact

    Directory of Open Access Journals (Sweden)

    Shetty S,

    2015-10-01

    Full Text Available A 79-year-old man with known Parkinson’s disease and status post deep brain stimulator (DBS implantation underwent an overnight polysomnogram for clinical suspicion of obstructive sleep apnea. Artifact was seen on the polysomnogram recording (Figures 1 & 2. Patient-related electrical artifacts may be seen from devices such as pacemakers, deep brain stimulators and vagal nerve simulators. Abrupt discontinuation of DBS is associated with a high likelihood of worsening of symptoms in patients with Parkinson’s disease (1. Patients with DBS are most commonly programmed in monopolar mode. Bipolar configuration, forms a short electrical dipole that affects a relatively smaller volume of tissue and generates far less artifact, suggesting that this may be an effective option in a Parkinsonian patient with indications for polysomnography (2.

  20. DBS artifact suppression using a time-frequency domain filter.

    Science.gov (United States)

    Santillán-Guzmán, Alina; Heute, Ulrich; Muthuraman, Muthuraman; Stephani, Ulrich; Galka, Andreas

    2013-01-01

    Electroencephalogram (EEG) is a useful tool for brain research. However, during Deep-Brain Stimulation (DBS), there are large artifacts that obscure the physiological EEG signals. In this paper, we aim at suppressing the DBS artifacts by means of a time-frequency-domain filter. As a pre-processing step, Empirical-Mode Decomposition (EMD) is applied to detrend the raw data. The detrended signals are then filtered iteratively until, by visual inspection, the quality is good enough for interpretation. The proposed algorithm is demonstrated by an application to a clinical DBS-EEG data set in resting state and in finger-tapping condition. Moreover, a comparison with a Low-Pass filter (LPF) is provided, by visual inspection and by a quantitative measure.

  1. Comparison of single-spot technique and RGB imaging for erythema index estimation.

    Science.gov (United States)

    Saknite, I; Zavorins, A; Jakovels, D; Spigulis, J; Kisis, J

    2016-03-01

    A commercially available point measurement device, the Mexameter(®), and an experimental RGB imaging prototype device were used for erythema index estimation of 50 rosacea patients by analysing the level of skin redness on the forehead, both cheeks and both sides of a nose. Results are compared with Clinician's Erythema Assessment (CEA) values given by two dermatologists. The Mexameter uses 568 nm and 660 nm LEDs and a photodetector for estimation of erythema index, while the used prototype device acquired RGB images at 460 nm, 530 nm and 665 nm LED illumination. Several erythema index estimation algorithms were compared to determine which one gives the best contrast between increased erythema and normal skin. The erythema index estimations and CEA values correlated much better for the RGB imaging data than for those obtained by the conventional Mexameter technique that is widely used by dermatologists and in clinical trials. In result, we propose an erythema index estimation approach that represents increased erythema with higher accuracy than other available methods.

  2. Assessment of the within- and between-lot variability of Whatman™ FTA(®) DMPK and 903(®) DBS papers and their suitability for the quantitative bioanalysis of small molecules.

    Science.gov (United States)

    Luckwell, Jacquelynn; Denniff, Philip; Capper, Stephen; Michael, Paul; Spooner, Neil; Mallender, Philip; Johnson, Barry; Clegg, Sarah; Green, Mark; Ahmad, Sheelan; Woodford, Lynsey

    2013-11-01

    To ensure that PK data generated from DBS samples are of the highest quality, it is important that the paper substrate is uniform and does not unduly contribute to variability. This study investigated any within and between lot variations for four cellulose paper types: Whatman™ FTA(®) DMPK-A, -B and -C, and 903(®) (GE Healthcare, Buckinghamshire, UK). The substrates were tested to demonstrate manufacturing reproducibility (thickness, weight, chemical coating concentration) and its effect on the size of the DBS produced, and the quantitative data derived from the bioanalysis of human DBS samples containing six compounds of varying physicochemical properties. Within and between lot variations in paper thickness, mass and chemical coating concentration were within acceptable manufacturing limits. No variation in the spot size or bioanalytical data was observed. Bioanalytical results obtained for DBS samples containing a number of analytes spanning a range of chemical space are not affected by the lot used or by the location within a lot.

  3. Extension of DQE to include scatter, grid, magnification, and focal spot blur: a new experimental technique and metric

    Science.gov (United States)

    Ranger, N. T.; Mackenzie, A.; Honey, I. D.; Dobbins, J. T., III; Ravin, C. E.; Samei, E.

    2009-02-01

    In digital radiography, conventional DQE evaluations are performed under idealized conditions that do not reflect typical clinical operating conditions. For this reason, we have developed and evaluated an experimental methodology for measuring theeffective detective quantum efficiency (eDQE) of digital radiographic systems and its utility in chest imaging applications.To emulate the attenuation and scatter properties of the human thorax across a range of sizes, the study employed pediatric and adult geometric chest imaging phantoms designed for use in the FDA/CDRH Nationwide Evaluation of X-Ray Trends (NEXT) program and a third phantom configuration designed to represent the bariatric population. The MTF for each phantom configuration was measured using images of an opaque edge device placed at the nominal surface of each phantom and at a common reference point. For each phantom, the NNPS was measured in a uniform region within the phantom image acquired at an exposure level determined from a prior phototimed acquisition. Scatter measurements were made using a beam-stop technique. These quantities were used along with measures of phantom attenuation and estimates of x-ray flux, to compute the eDQE at the beam-entrance surface of the phantoms, reflecting the presence of scatter, grid, magnification, and focal spot blur. The MTF results showed notable degradation due to focal spot blurring enhanced by geometric magnification, with increasing phantom size. Measured scatter fractions were 33%, 34% and 46% for the pediatric, adult, and bariatric phantoms, respectively. Correspondingly, the measured narrow beam transmission fractions were 16%, 9%, and 3%. The eDQE results for the pediatric and adult phantoms correlate well at low spatial frequencies but show degradation in the eDQE at increasing spatial frequencies for the adult phantom in comparison to the pediatric phantom. The results for the bariatric configuration showed a marked decrease in eDQE in comparison to

  4. White spots on Smoke rings by Bruce Nauman: a case study on contemporary art conservation using microanalytical techniques.

    Science.gov (United States)

    Mafalda, Ana Cardeira; da Câmara, Rodrigo Bettencourt; Strzelec, Patrick; Schiavon, Nick; Mirão, José; Candeias, António; Carvalho, Maria Luísa; Manso, Marta

    2015-02-01

    The artwork "Smoke Rings: Two Concentric Tunnels, Non-Communicating" by Bruce Nauman represents a case study of corrosion of a black patina-coated Al-alloy contemporary artwork. The main concern over this artwork was the widespread presence of white spots on its surface. Alloy substrate, patina, and white spots were characterized by means of energy-dispersive X-ray fluorescence and scanning electron microscopy with energy-dispersive spectroscopy. Alloy substrate was identified as an aluminum alloy 6,000 series Al-Si-Mg. Patina's identified composition confirmed the documentation provided by the atelier. Concerning the white spots, zircon particles were found on patina surface as external elements.

  5. Longitudinal impedance variability in patients with chronically implanted DBS devices.

    Science.gov (United States)

    Cheung, Tyler; Nuño, Miriam; Hoffman, Matilde; Katz, Maya; Kilbane, Camilla; Alterman, Ron; Tagliati, Michele

    2013-09-01

    Deep brain stimulation (DBS) is an effective therapy for advanced movement disorders, but its optimal use is still controversial. One factor that could play a role in the proper delivery of therapeutic stimulation by current DBS devices is the variability of the impedance at the interface between the electrode surface and surrounding tissue. To analyze variability and trends in the impedance of chronically-implanted DBS electrodes in subjects with movement disorders. We reviewed impedance values from medical records of DBS patients at an academic tertiary-care movement disorders center. The standard deviation of data recorded within individual subjects and single contacts were used as measures of longitudinal impedance variability. A generalized linear mixed model (GLMM) determined if a number of effects had significant influences on impedance. We analyzed 2863 impedance measurements from 94 subjects. Median variability, for subjects with follow-up from 6 months to 5 years (n = 77), was 194 Ω for individual subjects and 141 Ω for individual contacts, with a range spanning from 18 to over 600 Ω. The GLMM, incorporating all subjects (n = 94), identified time, electrical activity, implanted target, contact position on the electrode and side of implantation as significant predictors of impedance. Age and disease duration at surgery, gender or ethnicity were not significant predictors. Our analysis suggests that a significant amount of impedance variability can be expected in chronically implanted DBS electrodes and indicates a number of factors with possible predictive value. Further studies are needed to link impedance characteristics to clinical outcomes. Copyright © 2013 Elsevier Inc. All rights reserved.

  6. The influence of the dried blood spot drying time on the recoveries of six immunosuppressants

    Directory of Open Access Journals (Sweden)

    Remco A. Koster

    2015-10-01

    Full Text Available Investigation of the drying time of dried blood spots (DBS is currently not included in DBS validations. The influence of the DBS drying time on the recovery of tacrolimus, ascomycin, sirolimus, everolimus, cyclosporin A and temsirolimus was evaluated by measuring DBS with a fixed blood volume at a hematocrit range between 0.1 and 0.6 L/L at 3, 24 and 48 hours of drying time. Results showed that the recovery of sirolimus, everolimus, temsirolimus and cyclosporin A was influenced by the DBS drying time, while the recovery of tacrolimus and ascomycin was not. A drying time of at least 24 hours is advised in order to stabilize hematocrit and concentration related recovery effects of sirolimus, everolimus, temsirolimus and cyclosporin A.

  7. Evaluation of the dried blood spot filter paper technology and five testing strategies of HIV-1 and HIV-2 infections in West Africa

    NARCIS (Netherlands)

    Sarge-Njie, Ramu; Schim van der Loeff, Maarten; Ceesay, Saihou; Cubitt, David; Sabally, Saihou; Corrah, Tumani; Whittle, Hilton

    2006-01-01

    Simple robust approaches are needed to monitor the prevalence and incidence of HIV in Africa. The aim of this study was to evaluate the use of dried blood spot (DBS) as an alternative to serum or plasma for sentinel surveillance. Paired DBS and blood samples were obtained from 200 patients attending

  8. A novel dried blood spot-LCMS method for the quantification of methotrexate polyglutamates as a potential marker for methotrexate use in children.

    Directory of Open Access Journals (Sweden)

    Ahmed F Hawwa

    Full Text Available Development and validation of a selective and sensitive LCMS method for the determination of methotrexate polyglutamates in dried blood spots (DBS.DBS samples [spiked or patient samples] were prepared by applying blood to Guthrie cards which was then dried at room temperature. The method utilised 6-mm disks punched from the DBS samples (equivalent to approximately 12 µl of whole blood. The simple treatment procedure was based on protein precipitation using perchloric acid followed by solid phase extraction using MAX cartridges. The extracted sample was chromatographed using a reversed phase system involving an Atlantis T3-C18 column (3 µm, 2.1 × 150 mm preceded by Atlantis guard column of matching chemistry. Analytes were subjected to LCMS analysis using positive electrospray ionization.The method was linear over the range 5-400 nmol/L. The limits of detection and quantification were 1.6 and 5 nmol/L for individual polyglutamates and 1.5 and 4.5 nmol/L for total polyglutamates, respectively. The method has been applied successfully to the determination of DBS finger-prick samples from 47 paediatric patients and results confirmed with concentrations measured in matched RBC samples using conventional HPLC-UV technique.The methodology has a potential for application in a range of clinical studies (e.g. pharmacokinetic evaluations or medication adherence assessment since it is minimally invasive and easy to perform, potentially allowing parents to take blood samples at home. The feasibility of using DBS sampling can be of major value for future clinical trials or clinical care in paediatric rheumatology.

  9. THE USE OF DRIED BLOOD SPOTS AND A MODIFIED PARTICLE ...

    African Journals Online (AJOL)

    The use of dried blood spots (DBS) for the testing of HIV-1 antibodies has been described since 1988.' Numerous studies have proved that this method of prevalence testing has high sensitivity and specificity and is easy to use, as well as having the advantage of being less expensive than conventional tests on whole blood.

  10. Array elements for a DBS flat-plate antenna

    Science.gov (United States)

    Maddocks, M. C. D.

    1988-07-01

    The introduction of a direct broadcast by satellite (DBS) television service requires suitable receiving antennas to be available. An alternative to the parabolic dish antenna is a flat-plate antenna. The overall design of a circularly-polarized flat-plate antenna which can be mounted flat on the wall of a building has been considered in a companion Report. In this Report various types of elements are investigated and their advantages and disadvantages discussed. The most suitable element for use in a flat-plate array is identified as a linearly-polarized folded-dipole element; its performance is reported here. Linearly-polarized elements are found to perform better than circularly-polarized elements and could be used with a polarization converter to receive the circularly-polarized radiation that would be transmitted by DBS.

  11. Method for the Determination of Iodide in Dried Blood Spots from Newborns by High Performance Liquid Chromatography Tandem Mass Spectrometry.

    Science.gov (United States)

    Kim, Un-Jung; Kannan, Kurunthachalam

    2018-03-06

    Dried blood spots (DBS), collected for newborn screening programs in the United States, have been used to screen for congenital metabolic diseases in newborns for over 50 years. DBS provide an easy and inexpensive way to collect and store peripheral blood specimens and present an excellent resource for studies on the assessment of chemical exposures in newborns. In this study, a selective and sensitive method was developed for the analysis of iodide in DBS by high performance liquid chromatography electrospray tandem mass spectrometry. Accuracy, inter- and intraday precision, matrix effects, and detection limits of the method were determined. Further validation of the method was accomplished by concurrent analysis of whole blood and fortified blood spotted on a Whatman 903 filter card. A significant positive correlation was found between measured concentrations of iodide in venous whole blood and the same blood spotted as DBS. The method limit of detection was 0.15 ng/mL iodide. The method was further validated by the analysis of a whole blood sample certified for iodide levels (proficiency testing sample) by spotting on a filter card. Twenty DBS samples collected from newborns in New York State were analyzed to demonstrate the applicability of the method. The measured concentrations of iodide in whole blood of newborns from New York State ranged between DBS collected for epidemiological studies that investigate the importance of iodide on the health of newborns.

  12. Comparison of Proteins in Whole Blood and Dried Blood Spot Samples by LC/MS/MS

    Science.gov (United States)

    Chambers, Andrew G.; Percy, Andrew J.; Hardie, Darryl B.; Borchers, Christoph H.

    2013-09-01

    Dried blood spot (DBS) sampling methods are desirable for population-wide biomarker screening programs because of their ease of collection, transportation, and storage. Immunoassays are traditionally used to quantify endogenous proteins in these samples but require a separate assay for each protein. Recently, targeted mass spectrometry (MS) has been proposed for generating highly-multiplexed assays for biomarker proteins in DBS samples. In this work, we report the first comparison of proteins in whole blood and DBS samples using an untargeted MS approach. The average number of proteins identified in undepleted whole blood and DBS samples by liquid chromatography (LC)/MS/MS was 223 and 253, respectively. Protein identification repeatability was between 77 %-92 % within replicates and the majority of these repeated proteins (70 %) were observed in both sample formats. Proteins exclusively identified in the liquid or dried fluid spot format were unbiased based on their molecular weight, isoelectric point, aliphatic index, and grand average hydrophobicity. In addition, we extended this comparison to include proteins in matching plasma and serum samples with their dried fluid spot equivalents, dried plasma spot (DPS), and dried serum spot (DSS). This work begins to define the accessibility of endogenous proteins in dried fluid spot samples for analysis by MS and is useful in evaluating the scope of this new approach.

  13. Evaluation of dried blood spot samples for hepatitis C virus detection and quantification.

    Science.gov (United States)

    Marques, Brunna Lemos Crespo; do Espírito-Santo, Márcia Paschoal; Marques, Vanessa Alves; Miguel, Juliana Custódio; da Silva, Elisangela Ferreira; Villela-Nogueira, Cristiane Alves; Lewis-Ximenez, Lia Laura; Lampe, Elisabeth; Villar, Livia Melo

    2016-09-01

    Dried blood spots (DBS) could be an excellent alternative for HCV diagnosis, since it is less invasive and can be stored and transported without refrigeration. The aim of this study was to optimize quantitative and qualitative methods for HCV detection in DBS. DBS and serum samples were collected from 99 subjects (59 anti-HCV/HCV RNA positive and 40 seronegative samples). Seven extraction methods and different PCR parameters were evaluated in DBS samples in the quantitative RT-PCR (qRT-PCR) developed to amplify the 5' noncoding region of HCV. A qualitative PCR for amplification of NS5B region of HCV was also valued and the nested-PCR sequenced. The qRT-PCR showed good correlation to commercial assay for HCV viral measurement in serum. To quantify HCV RNA in DBS, it was necessary to increase reverse transcriptase and cDNA concentration. HCV RNA quantification in DBS demonstrated sensitivity of 65.9%, 100% of specificity and kappa statistic of 0.65. The median viral load of DBS samples was 5.38 log10 copies/ml (minimum value=1.76 and maximum value=10.48 log10 copies/ml). HCV RNA was detected in NS5B regions and nucleotide sequences obtained in 43 serum and 11 DBS samples. The presence of the same subtype was observed in paired serum and DBS samples. In this study, it was possible to demonstrate that, despite the low sensitivity, the optimized protocol was able to determine the viral load, as well as, the infecting HCV genotype, validating the usefulness of DBS for viral load determination and molecular epidemiology studies of HCV. Copyright © 2016 Elsevier B.V. All rights reserved.

  14. Miniaturized electrospraying as a technique for the production of microarrays of reproducible micrometer-sized protein spots.

    Science.gov (United States)

    Moerman, R; Frank, J; Marijnissen, J C; Schalkhammer, T G; van Dedem, G W

    2001-05-15

    Electrospraying in a stable cone-jet mode at N m(-1) and conductivities ranging from 0.04 to 2.2 S m(-1) were sprayed at ultralow flow rates ranging from 100 to 300 pL s(-1). The charged jet that emanates from the cone tip breaks up into a spray of charged droplets that are deposited in the form of a uniform spot of 130-350 microm in diameter by spraying during 0.5-3 s at 220-400 microm above a substrate, respectively. After a spot was deposited, spraying was stopped instantaneously by increasing the distance between the capillary tip and the substrate by an additional 100 microm using a computer-controlled x-y-z table. This was immediately followed by a rapid shift of the substrate 400 microm sideways and 100 microm upward, thus causing spraying to resume instantaneously because of the increased electric field strength, which resulted in the deposition of the next spot. It is shown here that spraying of lactate dehydrogenase (LDH), glucose-6-phosphate dehydrogenase (G6P-DH), and pyruvate kinase (PK) on a liquid layer resulted in the complete preservation of their activities despite the high solution conductivity of 3.3 S m(-1) and high currents ranging from 300 to 500 nA. LDH and PK activities were fully preserved after spraying onto dry aluminum by adding 0.05 M buffer and 0.5 and 1 wt % of trehalose, respectively, to the spray solutions. Electrospraying allows for accurate dispensing of liquid volumes as small as 50 pL. Enzymatic activities of LDH and PK are fully preserved after spraying.

  15. SU-F-T-189: Dosimetric Comparison of Spot-Scanning Proton Therapy Techniques for Liver Tumors Close to the Skin Surface

    Energy Technology Data Exchange (ETDEWEB)

    Takao, S; Matsuzaki, Y [Proton Beam Therapy Center, Hokkaido University Hospital, Sapporo, Hokkaido (Japan); Matsuura, T; Umegaki, K [Faculty of Engineering, Hokkaido University, Sapporo, Hokkaido (Japan); Global Institution for Collaborative Research and Education (GI-CoRE), Hokkaido University, Sapporo, Hokkaido (Japan); Fujii, Y; Fujii, T [Hokkaido University Graduate School of Medicine, Sapporo, Hokkaido (Japan); Katoh, N [Department of Radiation Oncology, Hokkaido University Hospital, Sapporo, Hokkaido (Japan); Shimizu, S; Shirato, H [Global Institution for Collaborative Research and Education (GI-CoRE), Hokkaido University, Sapporo, Hokkaido (Japan); Hokkaido University Graduate School of Medicine, Sapporo, Hokkaido (Japan)

    2016-06-15

    Purpose: Spot-scanning technique has been utilized to achieve conformal dose distribution to large and complicated tumors. This technique generally does not require patient-specific devices such as aperture and compensator. The commercially available spot-scanning proton therapy (SSPT) systems, however, cannot deliver proton beams to the region shallower than 4 g/cm2. Therefore some range compensation device is required to treat superficial tumors with SSPT. This study shows dosimetric comparison of the following treatment techniques: (i) with a tabletop bolus, (ii) with a nozzle-mounted applicator, and (iii) without any devices and using intensity-modulated proton therapy (IMPT) technique. Methods: The applicator composed of a combination of a mini-ridge filter and a range shifter has been manufactured by Hitachi, Ltd., and the tabletop bolus was made by .decimal, Inc. Both devices have been clinically implemented in our facility. Three patients with liver tumors close to the skin surface were examined in this study. Each treatment plan was optimized so that the prescription dose of 76 Gy(RBE) or 66 Gy(RBE) would be delivered to 99% of the clinical target volume in 20 fractions. Three beams were used for tabletop bolus plan and IMPT plan, whereas two beams were used in the applicator plan because the gantry angle available was limited due to potential collision to patient and couch. The normal liver, colon, and skin were considered as organs at risk (OARs). Results: The target heterogeneity index (HI = D{sub 5}/D{sub 95}) was 1.03 on average in each planning technique. The mean dose to the normal liver was considerably less than 20 Gy(RBE) in all cases. The dose to the skin could be reduced by 20 Gy(RBE) on average in the IMPT plan compared to the applicator plan. Conclusion: It has been confirmed that all treatment techniques met the dosimetric criteria for the OARs and could be implemented clinically.

  16. SU-F-T-189: Dosimetric Comparison of Spot-Scanning Proton Therapy Techniques for Liver Tumors Close to the Skin Surface

    International Nuclear Information System (INIS)

    Takao, S; Matsuzaki, Y; Matsuura, T; Umegaki, K; Fujii, Y; Fujii, T; Katoh, N; Shimizu, S; Shirato, H

    2016-01-01

    Purpose: Spot-scanning technique has been utilized to achieve conformal dose distribution to large and complicated tumors. This technique generally does not require patient-specific devices such as aperture and compensator. The commercially available spot-scanning proton therapy (SSPT) systems, however, cannot deliver proton beams to the region shallower than 4 g/cm2. Therefore some range compensation device is required to treat superficial tumors with SSPT. This study shows dosimetric comparison of the following treatment techniques: (i) with a tabletop bolus, (ii) with a nozzle-mounted applicator, and (iii) without any devices and using intensity-modulated proton therapy (IMPT) technique. Methods: The applicator composed of a combination of a mini-ridge filter and a range shifter has been manufactured by Hitachi, Ltd., and the tabletop bolus was made by .decimal, Inc. Both devices have been clinically implemented in our facility. Three patients with liver tumors close to the skin surface were examined in this study. Each treatment plan was optimized so that the prescription dose of 76 Gy(RBE) or 66 Gy(RBE) would be delivered to 99% of the clinical target volume in 20 fractions. Three beams were used for tabletop bolus plan and IMPT plan, whereas two beams were used in the applicator plan because the gantry angle available was limited due to potential collision to patient and couch. The normal liver, colon, and skin were considered as organs at risk (OARs). Results: The target heterogeneity index (HI = D 5 /D 95 ) was 1.03 on average in each planning technique. The mean dose to the normal liver was considerably less than 20 Gy(RBE) in all cases. The dose to the skin could be reduced by 20 Gy(RBE) on average in the IMPT plan compared to the applicator plan. Conclusion: It has been confirmed that all treatment techniques met the dosimetric criteria for the OARs and could be implemented clinically.

  17. Use of Dried Blood Spots to Elucidate Full-Length Transmitted/Founder HIV-1 Genomes

    Directory of Open Access Journals (Sweden)

    Jesus F. Salazar-Gonzalez

    2016-07-01

    Full Text Available Background: Identification of HIV-1 genomes responsible for establishing clinical infection in newly infected individuals is fundamental to prevention and pathogenesis research. Processing, storage, and transportation of the clinical samples required to perform these virologic assays in resource-limited settings requires challenging venipuncture and cold chain logistics. Here, we validate the use of dried-blood spots (DBS as a simple and convenient alternative to collecting and storing frozen plasma. Methods: We performed parallel nucleic acid extraction, single genome amplification (SGA, next generation sequencing (NGS, and phylogenetic analyses on plasma and DBS. Results: We demonstrated the capacity to extract viral RNA from DBS and perform SGA to infer the complete nucleotide sequence of the transmitted/founder (TF HIV-1 envelope gene and full-length genome in two acutely infected individuals. Using both SGA and NGS methodologies, we showed that sequences generated from DBS and plasma display comparable phylogenetic patterns in both acute and chronic infection. SGA was successful on samples with a range of plasma viremia, including samples as low as 1,700 copies/ml and an estimated ~50 viral copies per blood spot. Further, we demonstrated reproducible efficiency in gp160 env sequencing in DBS stored at ambient temperature for up to three weeks or at -20ºC for up to five months. Conclusions: These findings support the use of DBS as a practical and cost-effective alternative to frozen plasma for clinical trials and translational research conducted in resource-limited settings.

  18. Evaluation of DNA extraction methods for the detection of Cytomegalovirus in dried blood spots

    Science.gov (United States)

    Koontz, D.; Baecher, K.; Amin, M.; Nikolova, S.; Gallagher, M.; Dollard, S.

    2015-01-01

    Background Dried blood spots (DBS) are collected universally from newborns and may be valuable for the diagnosis of congenital Cytomegalovirus (CMV) infection. The reported analytical sensitivity for DBS testing compared to urine or saliva varies greatly across CMV studies. The purpose of this study was to directly compare the performance of various DNA extraction methods for identification of CMV in DBS including those used most often in CMV studies. Study design Whatman® Grade 903 filter paper cards were spotted with blood samples from 25 organ transplant recipients who had confirmed CMV viremia. Six DNA extraction methods were compared for relative yield of viral and cellular DNA: 2 manual solution-based methods (Gentra Puregene, thermal shock), 2 manual silica column-based methods (QIAamp DNA Mini, QIAamp DNA Investigator), and 2 automated methods (M48 MagAttract Mini, QIAcube Investigator). DBS extractions were performed in triplicate followed by real-time quantitative PCR (qPCR). Results For extraction of both viral and cellular DNA, two methods (QIAamp DNA Investigator and thermal shock) consistently gave the highest yields, and two methods (M48 MagAttract Mini and QIAamp DNA Mini) consistently gave the lowest yields. There was an average 3-fold difference in DNA yield between the highest and lowest yield methods. Conclusion The choice of DNA extraction method is a major factor in the ability to detect low levels of CMV in DBS and can largely account for the wide range of DBS sensitivities reported in studies to date. PMID:25866346

  19. Retinol analysis in dried blood spots by HPLC.

    Science.gov (United States)

    Craft, N E; Haitema, T; Brindle, L K; Yamini, S; Humphrey, J H; West, K P

    2000-04-01

    There are many advantages to measuring vitamin A in dried blood spots (DBS) from a finger prick as compared to plasma collected by venipuncture. The advantages include easier collection, transport and storage; accessibility to younger and more remote populations; and decreased risk of disease transmission. We describe a method for the extraction of retinol from DBS for analysis by HPLC and initial comparison to plasma retinol. The effects of various buffers, detergents, antioxidants and chelators were evaluated to establish the most effective approach to elute the retinol: retinol binding protein (holo-RBP) complex from the blood collection cards. The process involves ultrasonic agitation to elute holo-RBP into a phosphate buffer containing an antioxidant and metal chelator. The holo-RBP complex was denatured by the addition of ethanol containing additional antioxidants permitting the extraction of free retinol into hexane. Following solvent evaporation, the extract was dissolved in methanol for HPLC analysis. The initial measured retinol levels in freshly collected DBS declined for 6-10 d whether stored at 25, 4 or -20 degrees C, but remained consistent thereafter (homeostatic). By incorporating a "recovery/volume adjustment" factor, measured retinol values in homeostatic DBS were adjusted to the equivalent of plasma retinol. For 17 normal adults, the correlation coefficient was 0.90 between plasma retinol and adjusted DBS retinol in samples that had been stored at -70 degrees C for < 9 mo. The use of this new sample matrix for vitamin A assessment will allow access to previously unavailable populations.

  20. Quantification of DNA in Neonatal Dried Blood Spots by Adenine Tandem Mass Spectrometry.

    Science.gov (United States)

    Durie, Danielle; Yeh, Ed; McIntosh, Nathan; Fisher, Lawrence; Bulman, Dennis E; Birnboim, H Chaim; Chakraborty, Pranesh; Al-Dirbashi, Osama Y

    2018-01-02

    Newborn screening programs have expanded to include molecular-based assays as first-tier tests and the success of these assays depends on the quality and yield of DNA extracted from neonatal dried blood spots (DBS). To meet high throughput and rapid turnaround time requirements, newborn screening laboratories adopted rapid DNA extraction methods that produce crude extracts. Quantification of DNA in neonatal DBS is not routinely performed due to technical challenges; however, this may enhance the performance of assays that are sensitive to amounts of input DNA. In this study, we developed a novel high throughput method to quantify total DNA in DBS. It is based on specific acid-catalyzed depurination of DNA followed by mass spectrometric quantification of adenine. The amount of adenine was used to calculate DNA quantity per 3.2 mm DBS. Reference intervals were established using archived, neonatal DBS (n = 501) and a median of 130.6 ng of DNA per DBS was obtained, which is in agreement with literature values. The intra- and interday variations were quantification were 12.5 and 37.8 nmol/L adenine, respectively. We demonstrated that DNA from neonatal DBS can be successfully quantified in high throughput settings using instruments currently deployed in NBS laboratories.

  1. Evaluation of HBsAg and anti-HBc assays in saliva and dried blood spot samples according HIV status.

    Science.gov (United States)

    Flores, Geane Lopes; Cruz, Helena Medina; Potsch, Denise Vigo; May, Silvia Beatriz; Brandão-Mello, Carlos Eduardo; Pires, Marcia Maria Amendola; Pilotto, Jose Henrique; Lewis-Ximenez, Lia Laura; Lampe, Elisabeth; Villar, Livia Melo

    2017-09-01

    Influence of HIV status in HBV markers detection in saliva and dried blood spots (DBS) was not well established. This study aims to evaluate the performance of optimized commercial immunoassay for identifying HBsAg and anti-HBc in saliva and DBS according HIV status. A sum of 535 individuals grouped as HIV + , HBV + , HIV/HBV + and HIV/HBV- were recruited where 347 and 188 were included for HBsAg and anti-HBc evaluation, respectively. Serum, DBS collected in Whatman 903 paper and saliva obtained using salivette device were analyzed using EIA. Increased sample volume and ROC curve analysis for cut off determination were used for DBS and saliva testing. HBsAg detection in saliva and DBS exhibited sensitivities of 80.9% and 85.6% and specificities of 86.8% and 96.3%. Sensitivity of anti-HBc in saliva and DBS were 82.4% and 76.9% and specificities in saliva and DBS were 96.9% and 91.7%. Low sensitivities were observed for HBsAg (62%) and anti-HBc (47%) detection in saliva of HIV/HBV+ individuals. OD values were also lower for HBsAg detection in DBS and saliva of HIV/HBV+ individuals compared to their serum samples. Statistical significance was found for sensitivities in HBsAg detection between saliva and DBS demonstrating high sensitivity for DBS specimens. In conclusion, HIV status or antiretroviral treatment appears to interfere in the performance of HBsAg and anti-HBc detection in DBS and saliva samples using the adapted commercial EIA. Copyright © 2017 Elsevier B.V. All rights reserved.

  2. Whole exome and whole genome sequencing with dried blood spot DNA without whole genome amplification.

    Science.gov (United States)

    Bassaganyas, Laia; Freedman, George; Vaka, Dedeepya; Wan, Eunice; Lao, Richard; Chen, Flavia; Kvale, Mark; Currier, Robert J; Puck, Jennifer M; Kwok, Pui-Yan

    2018-01-01

    Newborn screening (NBS) for rare conditions is performed in all 50 states in the USA. We have partnered with the California Department of Public Health Genetic Disease Laboratory to determine whether sufficient DNA can be extracted from archived dried blood spots (DBS) for next-generation sequencing in the hopes that next-generation sequencing can play a role in NBS. We optimized the DNA extraction and sequencing library preparation protocols for residual infant DBS archived over 20 years ago and successfully obtained acceptable whole exome and whole genome sequencing data. This sequencing study using DBS DNA without whole genome amplification prior to sequencing library preparation provides evidence that properly stored residual newborn DBS are a satisfactory source of DNA for genetic studies. © 2017 Wiley Periodicals, Inc.

  3. Pyrosequencing dried blood spots reveals differences in HIV drug resistance between treatment naïve and experienced patients.

    Directory of Open Access Journals (Sweden)

    Hezhao Ji

    Full Text Available Dried blood spots (DBS are an alternative specimen collection format for HIV-1 genotyping. DBS produce HIV genotyping results that are robust and equivalent to plasma when using conventional sequencing methods. However, using tagged, pooled pyrosequencing, we demonstrate that concordance between plasma and DBS is not absolute and varies according to viral load (VL, duration of HIV infection and antiretroviral therapy (ART status. The plasma/DBS concordance is the highest when VL is ≥5,000 copies/ml and/or the patient has no ART exposure and/or when the duration of HIV infection is ≤2 years. Stepwise regression analysis revealed that VL is most important independent predictor for concordance of DBS with plasma genotypes. This is the first study to use next generation sequencing to identify discordance between DBS and plasma genotypes. Consideration should be given to VL, duration of infection, and ART exposure when interpreting DBS genotypes produced using next generation sequencing. These findings are of particular significance when DBS are to be used for clinical monitoring purposes.

  4. Age Spots

    Science.gov (United States)

    ... for Every Season How to Choose the Best Skin Care Products In This Section Dermatologic Surgery What is dermatologic ... for Every Season How to Choose the Best Skin Care Products Age Spots Treatment Options Learn more about treatment ...

  5. Regulation of vesicle transport and cell motility by Golgi-localized Dbs

    Science.gov (United States)

    Fitzpatrick, Ethan R; Hu, Tinghui; Ciccarelli, Bryan T; Whitehead, Ian P

    2014-01-01

    DBS/MCF2L has been recently identified as a risk locus for osteoarthritis. It encodes a guanine nucleotide exchange factor (Dbs) that has been shown to regulate both normal and tumor cell motility. In the current study, we have determined that endogenous Dbs is predominantly expressed as 2 isoforms, a 130 kDa form (Dbs-130) that is localized to the Golgi complex, and an 80 kDa form (Dbs-80) that is localized to the endoplasmic reticulum (ER). We have previously described an inhibitor that binds to the RhoGEF domain of Dbs and blocks its transforming activity. Here we show that the inhibitor localizes to the Golgi, where it specifically interacts with Dbs-130. Inhibition of endogenous Dbs-130 activity is associated with reduced levels of activated Cdc42, enlarged Golgi, and resistance to Brefeldin A-mediated Golgi dispersal, suggesting a role for Dbs in vesicle transport. Cells treated with the inhibitor exhibit normal protein transport from the ER to the Golgi, but are defective in transport from the Golgi to the plasma membrane. Inhibition of Dbs-130 in MDA-MB-231 human breast tumor cells limits motility in both transwell and wound healing assays, but appears to have no effect on the organization of the microtubule cytoskeleton. The reduced motility is associated with a failure to reorient the Golgi toward the leading edge. This is consistent with the Golgi localization, and suggests that the Dbs-130 regulates aspects of the secretory pathway that are required to support cell polarization during directed migration. PMID:25483302

  6. Landslide Detection Technique using multidate SPOT Imageries: A case study in Teradomari, Tochio and Shitada Mura, Niigata, Japan

    Directory of Open Access Journals (Sweden)

    I Nengah Surati Jaya

    2012-11-01

    Full Text Available 800x600 This study describes the use of multitemporal  principal component analisys (MPCA, vegetation index differencing (VIDN and  conventional maximum likelihood classifier (MLC for  detecting landslides.  The study found that the synthetic images derived from stable greenness, delta greenness and delta brightness of MPCA summarized the information of landslides effectively producing accuracy of 88% for Teradomari and 91% for Tochio and Shitada Mura.  The VIDN provides relatively lower accuracies than those from MPCA, i.e., only 62.5% for Teradomari and 64% for Tochio and Shitada Mura. The MLC method also provided very low user’s accuracy, i.e. 56.9% for Teradomari and 63.7% for Tochio and Shitada Mura but high producer’s accuracies, i.e. 100% for Teradomari and 98.3% for Tochio and Shitada Mura. The study also found that the landsides that could be detected should be more than the size of spatial resolution of the SPOT imagery, i.e. 10 m x 10 m. Detecting landslides using SPOT imagery is more efficient than using only ground survey, providing an efficiency of 2.7.    Keywords: Analisis komponen utama multiwaktu (Multitemporal  principal component analisys, disparitas indeks vegetasi (vegetation index differencing, metode peluang maksimum (maximum likelihood classifier, kestabilan kehijauan (stable greenness, perubahan kehijauan (delta greenness, perubahan kecerahan (delta brighntess dan efisiensi relatif (efficiency relative Normal 0 false false false IN X-NONE X-NONE MicrosoftInternetExplorer4 /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Table Normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-priority:99; mso-style-parent:""; mso-padding-alt:0cm 5.4pt 0cm 5.4pt; mso-para-margin:0cm; mso-para-margin-bottom:.0001pt; mso-pagination:widow-orphan; font-size:10.0pt; font-family:"Times New Roman","serif";}

  7. Basic mechanisms of DBS for Parkinson’s disease: computational and experimental studies on neural dynamics

    NARCIS (Netherlands)

    Çağnan, H.

    2010-01-01

    Deep Brain Stimulation (DBS) has become an accepted therapy of last resort for Parkinson’s disease (PD). The acceptance of DBS for the management of PD motor symptoms is based on its success rate and contrasts sharply with ones understanding of the pathophysiology underlying the disease state and

  8. Corticomuscular coherence during hand gripping with DBS and medication in PD patients

    DEFF Research Database (Denmark)

    Sridharan, Kousik Sarathy; Højlund, Andreas; Johnsen, Erik Lisbjerg

    Deep brain stimulation (DBS) effectively alleviates the motor symptoms in Parkinson’s disease (PD) although its effect mechanism is still unclear. CMC is reduced in PD patients but restorable with medication, while DBS variably affects CMC in advanced PD patients. We recorded magnetoencephalography...

  9. PyDBS: an automated image processing workflow for deep brain stimulation surgery.

    Science.gov (United States)

    D'Albis, Tiziano; Haegelen, Claire; Essert, Caroline; Fernández-Vidal, Sara; Lalys, Florent; Jannin, Pierre

    2015-02-01

    Deep brain stimulation (DBS) is a surgical procedure for treating motor-related neurological disorders. DBS clinical efficacy hinges on precise surgical planning and accurate electrode placement, which in turn call upon several image processing and visualization tasks, such as image registration, image segmentation, image fusion, and 3D visualization. These tasks are often performed by a heterogeneous set of software tools, which adopt differing formats and geometrical conventions and require patient-specific parameterization or interactive tuning. To overcome these issues, we introduce in this article PyDBS, a fully integrated and automated image processing workflow for DBS surgery. PyDBS consists of three image processing pipelines and three visualization modules assisting clinicians through the entire DBS surgical workflow, from the preoperative planning of electrode trajectories to the postoperative assessment of electrode placement. The system's robustness, speed, and accuracy were assessed by means of a retrospective validation, based on 92 clinical cases. The complete PyDBS workflow achieved satisfactory results in 92 % of tested cases, with a median processing time of 28 min per patient. The results obtained are compatible with the adoption of PyDBS in clinical practice.

  10. SPOT Program

    Science.gov (United States)

    Smith, Jason T.; Welsh, Sam J.; Farinetti, Antonio L.; Wegner, Tim; Blakeslee, James; Deboeck, Toni F.; Dyer, Daniel; Corley, Bryan M.; Ollivierre, Jarmaine; Kramer, Leonard; hide

    2010-01-01

    A Spacecraft Position Optimal Tracking (SPOT) program was developed to process Global Positioning System (GPS) data, sent via telemetry from a spacecraft, to generate accurate navigation estimates of the vehicle position and velocity (state vector) using a Kalman filter. This program uses the GPS onboard receiver measurements to sequentially calculate the vehicle state vectors and provide this information to ground flight controllers. It is the first real-time ground-based shuttle navigation application using onboard sensors. The program is compact, portable, self-contained, and can run on a variety of UNIX or Linux computers. The program has a modular objec-toriented design that supports application-specific plugins such as data corruption remediation pre-processing and remote graphics display. The Kalman filter is extensible to additional sensor types or force models. The Kalman filter design is also strong against data dropouts because it uses physical models from state and covariance propagation in the absence of data. The design of this program separates the functionalities of SPOT into six different executable processes. This allows for the individual processes to be connected in an a la carte manner, making the feature set and executable complexity of SPOT adaptable to the needs of the user. Also, these processes need not be executed on the same workstation. This allows for communications between SPOT processes executing on the same Local Area Network (LAN). Thus, SPOT can be executed in a distributed sense with the capability for a team of flight controllers to efficiently share the same trajectory information currently being computed by the program. SPOT is used in the Mission Control Center (MCC) for Space Shuttle Program (SSP) and International Space Station Program (ISSP) operations, and can also be used as a post -flight analysis tool. It is primarily used for situational awareness, and for contingency situations.

  11. Diagnosis of Morquio Syndrome in Dried Blood Spots Based on a New MRM-MS Assay.

    Directory of Open Access Journals (Sweden)

    Claudia Cozma

    Full Text Available Mucopolysaccharidosis IVA (MPS IVA; Morquio A disease is an autosomal recessive disease caused and characterized by a decreased activity of N-acetylgalactosamine-6-sulfate sulfatase (GALNS, resulting in accumulation of keratan sulfate and chondroitin-6-sulfate in tissues and secondary organ damage. Recently approved enzyme replacement therapy renders the easy and early identification of MPS IVA of out-most importance.We propose a completely new assay for the stable and reproducible detection of GALNS deficiency in dry blood spots (DBS. For the validation blood samples were taken from 59 healthy individuals and 24 randomly selected genetically confirmed MPS IVA patients. The material extracted from DBS was incubated with a 4-methylumbelliferyl-β-D-galactopyranoside-6-sulfate as a specific substrate. Final enzymatic product, 4-methylumbelliferone, obtained after adding exogenous beta-galactosidase, was quantified by LC/MRM-MS (liquid-chromatography/multiple-reaction-monitoring mass-spectrometry. 4-propyl-5-hydroxy-7-methyl-2h-chromen-2-one was used as internal standard, a compound with a similar molecular structure and fragmentation pattern in negative ion mode as 4-methylumbelliferone.The enzymatic assay yielded a positive and negative predictive value of 1.0 for genetically confirmed MPS IVA patients (GALNS activity of 0.35 ± 0.21 μmol/L/h and for controls with normal GALNS activity (23.1 ± 5.3 μmol/L /h. With present enzymatic conditions, the reaction yield in dried blood spots is at least 20 fold higher than any previously reported data with other assays.The present LC/MRM-MS based assay for MPS IVA diagnosis provides an easy, highly-standardized, accurate and innovative quantification of the enzymatic product in vitro and distinguishes perfectly between MPS IVA affected patients and normal controls. This technique will significantly simplify the early detection of MPS IVA patients.

  12. Diagnosis of Morquio Syndrome in Dried Blood Spots Based on a New MRM-MS Assay.

    Science.gov (United States)

    Cozma, Claudia; Eichler, Sabrina; Wittmann, Gyula; Flores Bonet, Alba; Kramp, Guido Johannes; Giese, Anne-Katrin; Rolfs, Arndt

    2015-01-01

    Mucopolysaccharidosis IVA (MPS IVA; Morquio A disease) is an autosomal recessive disease caused and characterized by a decreased activity of N-acetylgalactosamine-6-sulfate sulfatase (GALNS), resulting in accumulation of keratan sulfate and chondroitin-6-sulfate in tissues and secondary organ damage. Recently approved enzyme replacement therapy renders the easy and early identification of MPS IVA of out-most importance. We propose a completely new assay for the stable and reproducible detection of GALNS deficiency in dry blood spots (DBS). For the validation blood samples were taken from 59 healthy individuals and 24 randomly selected genetically confirmed MPS IVA patients. The material extracted from DBS was incubated with a 4-methylumbelliferyl-β-D-galactopyranoside-6-sulfate as a specific substrate. Final enzymatic product, 4-methylumbelliferone, obtained after adding exogenous beta-galactosidase, was quantified by LC/MRM-MS (liquid-chromatography/multiple-reaction-monitoring mass-spectrometry). 4-propyl-5-hydroxy-7-methyl-2h-chromen-2-one was used as internal standard, a compound with a similar molecular structure and fragmentation pattern in negative ion mode as 4-methylumbelliferone. The enzymatic assay yielded a positive and negative predictive value of 1.0 for genetically confirmed MPS IVA patients (GALNS activity of 0.35 ± 0.21 μmol/L/h) and for controls with normal GALNS activity (23.1 ± 5.3 μmol/L /h). With present enzymatic conditions, the reaction yield in dried blood spots is at least 20 fold higher than any previously reported data with other assays. The present LC/MRM-MS based assay for MPS IVA diagnosis provides an easy, highly-standardized, accurate and innovative quantification of the enzymatic product in vitro and distinguishes perfectly between MPS IVA affected patients and normal controls. This technique will significantly simplify the early detection of MPS IVA patients.

  13. Dark Spots

    Science.gov (United States)

    2006-01-01

    Dark spots (left) and 'fans' appear to scribble dusty hieroglyphics on top of the Martian south polar cap in two high-resolution Mars Global Surveyor, Mars Orbiter Camera images taken in southern spring. Each image is about 3-kilometers wide (2-miles).

  14. Deep brain stimulation during pregnancy and delivery: experience from a series of DBS babies

    Directory of Open Access Journals (Sweden)

    Emma eSCELZO

    2015-09-01

    Full Text Available Introduction: Deep brain stimulation (DBS is widely used to improve quality of life in movement disorders and psychiatric diseases. Even though the ability to have children has a big impact on patients’ life, only a few studies describe the role of DBS in pregnancy. Objective: To describe risks and management of women treated by DBS for disabling movement disorders (MD or psychiatric diseases during pregnancy and delivery. Methods: We report a retrospective case series of women, followed in two DBS centers, who became pregnant and went on to give birth to a child while suffering from disabling MD or psychiatric diseases (Parkinson’s disease (PD, dystonia, Tourette’s syndrome (TS, Obsessive Compulsive Disorder (OCD treated by DBS. Clinical status, complications and management before, during and after pregnancy are reported. Two illustrative cases are described in greater detail.Results: DBS improved motor and behavioural disorders in all patients and allowed reduction in, or even total interruption of disease-specific medication during pregnancy. With the exception of the spontaneous early abortion of one fetus in a twin pregnancy, all pregnancies were uneventful in terms of obstetric and pediatric management. DBS parameters were adjusted in five patients in order to limit clinical worsening during pregnancy. Implanted material limited breast-feeding in one patient because of local pain at submammal stimulator site and led to local discomfort related to stretching of the cable with increasing belly size in another patient whose stimulator was implanted in the abdominal wall. Conclusions: Not only is it safe for young women with MD, TS and OCD who have a DBS-System implanted to become pregnant and give birth to a baby but DBS seems to be the key to becoming pregnant, having children, and thus greatly improves quality of life.

  15. Robustness of genome-wide scanning using archived dried blood spot samples as a DNA source

    Directory of Open Access Journals (Sweden)

    Børglum Anders D

    2011-07-01

    Full Text Available Abstract Background The search to identify disease-susceptible genes requires access to biological material from numerous well-characterized subjects. Archived residual dried blood spot (DBS samples, also known as Guthrie cards, from national newborn screening programs may provide a DNA source for entire populations. Combined with clinical information from medical registries, DBS samples could provide a rich source for productive research. However, the amounts of DNA which can be extracted from these precious samples are minute and may be prohibitive for numerous genotypings. Previously, we demonstrated that DBS DNA can be whole-genome amplified and used for reliable genetic analysis on different platforms, including genome-wide scanning arrays. However, it remains unclear whether this approach is workable on a large sample scale. We examined the robustness of using DBS samples for whole-genome amplification following genome-wide scanning, using arrays from Illumina and Affymetrix. Results This study is based on 4,641 DBS samples from the Danish Newborn Screening Biobank, extracted for three separate genome-wide association studies. The amount of amplified DNA was significantly (P Conclusion Our study indicates that archived DBS samples from the Danish Newborn Screening Biobank represent a reliable resource of DNA for whole-genome amplification and subsequent genome-wide association studies. With call-rates equivalent to high quality DNA samples, our results point to new opportunities for using the neonatal biobanks available worldwide in the hunt for genetic components of disease.

  16. Optimized DNA extraction from neonatal dried blood spots: application in methylome profiling

    Science.gov (United States)

    2014-01-01

    Background Neonatal dried blood spots (DBS) represent an inexpensive method for long-term biobanking worldwide and are considered gold mines for research for several human diseases, including those of metabolic, infectious, genetic and epigenetic origin. However, the utility of DBS is restricted by the limited amount and quality of extractable biomolecules (including DNA), especially for genome wide profiling. Degradation of DNA in DBS often occurs during storage and extraction. Moreover, amplifying small quantities of DNA often leads to a bias in subsequent data, particularly in methylome profiles. Thus it is important to develop methodologies that maximize both the yield and quality of DNA from DBS for downstream analyses. Results Using combinations of in-house-derived and modified commercial extraction kits, we developed a robust and efficient protocol, compatible with methylome studies, many of which require stringent bisulfite conversion steps. Several parameters were tested in a step-wise manner, including blood extraction, cell lysis, protein digestion, and DNA precipitation, purification and elution. DNA quality was assessed based on spectrophotometric measurements, DNA detectability by PCR, and DNA integrity by gel electrophoresis and bioanalyzer analyses. Genome scale Infinium HumanMethylation450 and locus-specific pyrosequencing data generated using the refined DBS extraction protocol were of high quality, reproducible and consistent. Conclusions This study may prove useful to meet the increased demand for research on prenatal, particularly epigenetic, origins of human diseases and for newborn screening programs, all of which are often based on DNA extracted from DBS. PMID:24980254

  17. The development and validation of dried blood spots for external quality assurance of syphilis serology.

    Science.gov (United States)

    Smit, Pieter W; van der Vlis, Thomas; Mabey, David; Changalucha, John; Mngara, Julius; Clark, Benjamin D; Andreasen, Aura; Todd, Jim; Urassa, Mark; Zaba, Basia; Peeling, Rosanna W

    2013-02-26

    Syphilis causes up to 1,500,000 congenital syphilis cases annually. These could be prevented if all pregnant women were screened, and those with syphilis treated with a single dose of penicillin before 28 weeks gestation. In recent years, rapid point-of-care tests have allowed greater access to syphilis screening, especially in rural or remote areas, but the lack of quality assurance of rapid testing has been a concern. We determined the feasibility of using dried blood spots (DBS) as specimens for quality assurance of syphilis serological assays. We developed DBS extraction protocols for use with Treponema pallidum particle agglutination assay (TPPA), Treponema pallidum haemagglutination assay (TPHA) and an enzyme immunoassay (EIA) and compared the results with those using matching plasma samples from the same patient. Since DBS samples showed poor performance with TPHA and EIA (TPHA sensitivity was 50.5% (95% confidence interval: 39.9-61.2%) and EIA specificity was 50.4% (95% CI: 43.7-57.1%), only the DBS TPPA was used in the final evaluation. DBS TPPA showed an sensitivity of 95.5% (95% CI: 91.3-98.0%) and a specificity of 99.0% (95% CI: 98.1-99.5%) compared to TPPA using plasma samples as a reference. DBS samples can be recommended for use with TPPA, and may be of value for external quality assurance of point-of-care syphilis testing.

  18. Validation and modification of dried blood spot-based glycosylated hemoglobin assay for the longitudinal aging study in India.

    Science.gov (United States)

    Hu, Peifeng; Edenfield, Michael; Potter, Alan; Kale, Varsha; Risbud, Arun; Williams, Sharon; Lee, Jinkook; Bloom, David E; Crimmins, Eileen; Seeman, Teresa

    2015-01-01

    This study aims to validate a modified dried blood spot (DBS)-based glycosylated hemoglobin (HbA1c) assay protocol, after a pretest in India showed poor correlation between the original DBS-based protocol and venous results. The original protocol was tested on different chemistry analyzers and then simplified at the University of Washington (UW). A second pretest was conducted in India to validate the modified assay protocol, using 44 quality control specimens. Data from UW indicated that, using the original protocol, the correlation coefficients between DBS and venous results were above 0.98 on both Bio-Rad and Olympus chemistry analyzers. The protocol worked equally well on filter paper, with or without pre-treatment, and when the recommended amount of blood spot material, or less, was used. A second pretest of the modified protocol confirmed that DBS-based levels from both Olympus and Roche chemistry analyzers were well correlated with DBS results from UW (correlation coefficients were above 0.96), as well as with venous values (correlation coefficients were above 0.94). The DBS-based HbA1c values are highly correlated with venous results. The pre-treatment of filter paper does not appear to be necessary. The poor results from the first pretest are probably due to factors unrelated to the protocol, such as problems with the chemistry analyzer or assay reagents. © 2015 Wiley Periodicals, Inc.

  19. Cytomegalovirus antibodies in dried blood spots: a minimally invasive method for assessing stress, immune function, and aging

    Directory of Open Access Journals (Sweden)

    Chyu Laura

    2011-01-01

    Full Text Available Abstract Background Cytomegalovirus (CMV is a prevalent herpesvirus with links to both stress and aging. This paper describes and validates a minimally invasive method for assessing antibodies against CMV in finger stick whole blood spot samples for use as an indirect marker of an aspect of cell-mediated immunity. Results Analysis of CMV in dried blood spot samples (DBS was based on modifications of a commercially available protocol for quantifying CMV antibodies in serum or plasma. The method was evaluated through analysis of precision, reliability, linearity, and correlation between matched serum and DBS samples collected from 75 volunteers. Correlation between DBS and plasma values was linear and high (Pearson correlation R = .96, and precision, reliability, and linearity of the DBS assay were within acceptable ranges. Conclusions The validity of a DBS assay for CMV antibodies will enable its inclusion in population-based surveys and other studies collecting DBS samples in non-clinical settings, increasing scientific understanding of the interaction of social and biological stress and immune function.

  20. Quantitative analysis of methyl and propyl parabens in neonatal DBS using LC-MS/MS.

    Science.gov (United States)

    Yakkundi, Shirish; Mulla, Hussain; Pandya, Hitesh; Turner, Mark A; McElnay, James

    2016-06-01

    Excipients are used to overcome the chemical, physical and microbiological challenges posed by developing formulated medicines. Both methyl and propyl paraben are commonly used in pediatric liquid formulations. There is no data on systemic exposure to parabens in neonates. The European Study of Neonatal Exposure to Excipients project has investigated this. Results & methodology: DBS sampling was used to collect opportunistic blood samples. Parabens were extracted from the DBS and analyzed using a validated LC-MS/MS assay. The above assay was applied to analyze neonatal DBS samples. The blood concentrations of parabens in neonates confirm systemic exposure to parabens following administration of routine medicines.

  1. Estimation of HIV-1 DNA Level Interfering with Reliability of HIV-1 RNA Quantification Performed on Dried Blood Spots Collected from Successfully Treated Patients

    OpenAIRE

    Zida, Sylvie; Tuaillon, Edouard; Barro, Makoura; Kwimatouo Lekpa Franchard, Arnaud; Kagoné, Thérèse; Nacro, Boubacar; Ouedraogo, Abdoul Salam; Bolloré, Karine; Sanosyan, Armen; Plantier, Jean-Christophe; Meda, Nicolas; Sangaré, Lassana; Rouzioux, Christine; Rouet, François; Kania, Dramane

    2016-01-01

    The impact of HIV-1 DNA coamplification during HIV-1 RNA quantification on dried blood spots (DBS) was explored. False-positive HIV RNA detection (22/62, 35%) was associated with high HIV-1 DNA levels. Specificity of HIV-1 RNA assays on DBS should be evaluated following manufacturer protocols on samples with HIV-1 DNA levels of ≥1,000 copies/106 peripheral blood mononuclear cells.

  2. Congenital cytomegalovirus: association between dried blood spot viral load and hearing loss.

    Science.gov (United States)

    Walter, S; Atkinson, C; Sharland, M; Rice, P; Raglan, E; Emery, V C; Griffiths, P D

    2008-07-01

    To investigate the relation between cytomegalovirus (CMV) viral load on dried blood spots (DBS) from newborn biochemical screening ("Guthrie") cards, and sensorineural hearing loss (SNHL) in congenital CMV. Cross-sectional study with retrospective case-note review. Seven paediatric audiology departments in the United Kingdom. 84 children, median age 7 years: 43 with known congenital CMV, 41 with unexplained SNHL. Half a DBS was tested for CMV DNA viral load by quantitative real-time polymerase chain reaction (PCR). Pure tone average hearing thresholds (0.5-4 kHz). DBS CMV DNA viral load significantly correlated with hearing thresholds for the worse and better hearing ears (Spearman's rank correlations: r = 0.445, p = 0.008 and r = 0.481, p = 0.004 respectively). Multivariable logistic regression showed that the effect of DBS viral load on the risk of SNHL remained important, when age and central nervous system involvement had been taken into account (odds ratio (OR) 2.76, 95% confidence interval (CI) 1.14 to 6.63, p = 0.024). The mean log DBS viral load was significantly higher in children with SNHL than in those with normal hearing (2.69 versus 1.64, 95% CI -1.84 to -0.27, p = 0.01). 8/35 (23%) children with unexplained SNHL tested positive for CMV DNA on DBS. One false positive result was obtained. The risk of SNHL increased with DBS viral load. Further studies should investigate whether DBS CMV testing has a role in identifying asymptomatic congenitally infected neonates at risk of SNHL, and whether antiviral treatment can reduce this risk.

  3. Comparison of Hepatitis C Virus RNA and antibody detection in dried blood spots and plasma specimens.

    Science.gov (United States)

    Dokubo, E Kainne; Evans, Jennifer; Winkelman, Valerie; Cyrus, Sherri; Tobler, Leslie H; Asher, Alice; Briceno, Alya; Page, Kimberly

    2014-04-01

    Current diagnostic tests for Hepatitis C Virus (HCV) involve phlebotomy and serologic testing for HCV antibodies (anti-HCV) and RNA, which are not always feasible. Dried blood spots (DBS) present a minimally invasive sampling method and are suitable for sample collection, storage and testing. To assess the utility of DBS in HCV detection, we evaluated the sensitivity and specificity of DBS for anti-HCV and HCV RNA detection compared to plasma specimens. This cross-sectional validation study was conducted in the context of an existing prospective study of HCV in young injection drug users. Blood samples were collected by venipuncture into serum separator tubes (SST) and via finger stick onto Whatman 903(®) protein-saver cards. Plasma samples and eluates from the DBS were tested for anti-HCV using either a third generation enzyme-linked or chemiluminescent immunoassay (IA), and HCV RNA using discriminatory HCV transcription-mediated amplification assay (dHCV TMA). DBS results were compared to their corresponding plasma sample results. 148 participants were tested for anti-HCV and 132 participants were tested for HCV RNA. For anti-HCV, the sensitivity of DBS was 70%, specificity was 100%, positive predictive value (PPV) was 100%, negative predictive value (NPV) was 76% and Kappa was 0.69. For HCV RNA, the sensitivity of DBS was 90%, specificity was 100%, PPV was 100%, NPV was 94% and Kappa was 0.92. DBS are sensitive and very specific in detecting anti-HCV and HCV RNA, demonstrate good correlation with plasma results, and have potential to facilitate diagnosis of HCV infection. Copyright © 2014 Elsevier B.V. All rights reserved.

  4. Monitoring the onset of neuromuscular blockade with double burst stimulation (DBS).

    Science.gov (United States)

    Gorgias, N; Maidatsi, P; Zaralidou, A; Ourailoglou, V; Fakidou, A; Giala, M

    1998-11-01

    The present study was undertaken to evaluate the suitability of the DBS mode in the determination of the proper time to perform tracheal intubation following cisatracurium muscle relaxation. The DBS3.3 pattern was administered to the ulnar nerve at the wrist in 45 patients paralyzed with cisatracurium 0.15 mg.kg-1 and tracheal intubation was attempted immediately after the disappearance of both palpable contractions of the adductor pollicis. Intubation conditions were assessed with a standard four-graded scoring system and the onset time of the relaxant was determined. Forty-two patients (93%) exhibited acceptable intubation conditions as soon as both responses to DBS were absent and the estimated apparent onset time, according to the stimulation mode applied, was 114.68 +/- 13.2 sec. Our data suggest that disappearance of both palpable responses to DBS3.3 may be used as an accurate predictor of acceptable intubation conditions, following nondepolarizing relaxants such as cisatracurium.

  5. New methods of minimally invasive brain modulation as therapies in psychiatry: TMS, MST, VNS and DBS.

    Science.gov (United States)

    George, Mark S

    2002-08-01

    Over the past 20 years, new methods have been developed that have allowed scientists to visualize the human brain in action. Initially positron emission tomography (PET) and now functional magnetic resonance imaging (fMRI) are causing a paradigm shift in psychiatry and the neurosciences. Psychiatry is abandoning the pharmacological model of 'brain as soup', used for much of the past 20 years. Instead, there is new realization that both normal and abnormal behavior arise from chemical processes that occur within parallel distributed networks in specific brain regions. Many of these pathological circuits are becoming well characterized, in disorders ranging from Parkinson's disease, to obsessive-compulsive disorder, to depression. Most recently, there has been an explosion of new techniques that allow for direct stimulation of these brain circuits, without the need for open craniotomy and neurosurgical ablation. The techniques include transcranial magnetic stimulation (TMS), magnetic seizure therapy (MST), vagus nerve stimulation (VNS), and deep brain stimulation (DBS). This review will describe these new tools, and overview their current and future potential for research and clinical neuropsychiatric use. The psychiatry of the future will be better grounded in a firm understanding of neuroanatomy and neurophysiology (as well as pharmacology). These brain stimulation tools, or their next iterations, will play an ever-larger role in clinical neuropsychiatric practice.

  6. Quantitative analysis of methyl and propyl parabens in neonatal DBS using LC–MS/MS

    OpenAIRE

    Yakkundi, Shirish; Mulla, Hussain; Pandya, Hitesh; Turner, Mark A; McElnay, James

    2016-01-01

    Aim: Excipients are used to overcome the chemical, physical and microbiological challenges posed by developing formulated medicines. Both methyl and propyl paraben are commonly used in pediatric liquid formulations. There is no data on systemic exposure to parabens in neonates. The European Study of Neonatal Exposure to Excipients project has investigated this. Results & methodology: DBS sampling was used to collect opportunistic blood samples. Parabens were extracted from the DBS and ana...

  7. Estimating canopy cover in forest stands used by Mexican spotted owls: Do stand-exam routines provide estimates comparable to field-based techniques?

    Science.gov (United States)

    Joseph L. Ganey; Regis H. Cassidy; William M. Block

    2008-01-01

    Canopy cover has been identified as an important correlate of Mexican spotted owl (Strix occidentalis lucida) habitat, yet management guidelines in a 1995 U.S. Fish and Wildlife Service recovery plan for the Mexican spotted owl did not address canopy cover. These guidelines emphasized parameters included in U.S. Forest Service stand exams, and...

  8. DBS Programming: An Evolving Approach for Patients with Parkinson’s Disease

    Directory of Open Access Journals (Sweden)

    Aparna Wagle Shukla

    2017-01-01

    Full Text Available Deep brain stimulation (DBS surgery is a well-established therapy for control of motor symptoms in Parkinson’s disease. Despite an appropriate targeting and an accurate placement of DBS lead, a thorough and efficient programming is critical for a successful clinical outcome. DBS programming is a time consuming and laborious manual process. The current approach involves use of general guidelines involving determination of the lead type, electrode configuration, impedance check, and battery check. However there are no validated and well-established programming protocols. In this review, we will discuss the current practice and the recent advances in DBS programming including the use of interleaving, fractionated current, directional steering of current, and the use of novel DBS pulses. These technological improvements are focused on achieving a more efficient control of clinical symptoms with the least possible side effects. Other promising advances include the introduction of computer guided programming which will likely impact the efficiency of programming for the clinicians and the possibility of remote Internet based programming which will improve access to DBS care for the patients.

  9. Mongolian spots

    Directory of Open Access Journals (Sweden)

    Divya Gupta

    2013-01-01

    Full Text Available Mongolian spots (MS are birthmarks that are present at birth and their most common location is sacrococcygeal or lumbar area. Lesions may be single or multiple and usually involve < 5% total body surface area. They are macular and round, oval or irregular in shape. The color varies from blue to greenish, gray, black or a combination of any of the above. The size varies from few to more than 20 centimetres. Pigmentation is most intense at the age of one year and gradually fades thereafter. It is rarely seen after the age of 6 years. Aberrant MS over occiput, temple, mandibular area, shoulders and limbs may be confused with other dermal melanocytoses and bruises secondary to child abuse, thus necessitating documentation at birth. Although regarded as benign, recent data suggest that MS may be associated with inborn errors of metabolism and neurocristopathies. Mongolian spots usually resolve by early childhood and hence no treatment is generally needed if they are located in the sacral area. However, sometimes it may be required for extrasacral lesions for cosmesis.

  10. Subject-specific computational modeling of DBS in the PPTg area

    Directory of Open Access Journals (Sweden)

    Laura M. Zitella

    2015-07-01

    Full Text Available Deep brain stimulation (DBS in the pedunculopontine tegmental nucleus (PPTg has been proposed to alleviate medically intractable gait difficulties associated with Parkinson’s disease. Clinical trials have shown somewhat variable outcomes, stemming in part from surgical targeting variability, modulating fiber pathways implicated in side effects, and a general lack of mechanistic understanding of DBS in this brain region. Subject-specific computational models of DBS are a promising tool to investigate the underlying therapy and side effects. In this study, a parkinsonian rhesus macaque was implanted unilaterally with an 8-contact DBS lead in the PPTg region. Fiber tracts adjacent to PPTg, including the oculomotor nerve, central tegmental tract, and superior cerebellar peduncle, were reconstructed from a combination of pre-implant 7T MRI, post-implant CT, and post-mortem histology. These structures were populated with axon models and coupled with a finite element model simulating the voltage distribution in the surrounding neural tissue during stimulation. This study introduces two empirical approaches to evaluate model parameters. First, incremental monopolar cathodic stimulation (20Hz, 90µs pulse width was evaluated for each electrode, during which a right eyelid flutter was observed at the proximal four contacts (-1.0 to -1.4mA. These current amplitudes followed closely with model predicted activation of the oculomotor nerve when assuming an anisotropic conduction medium. Second, PET imaging was collected OFF-DBS and twice during DBS (two different contacts, which supported the model predicted activation of the central tegmental tract and superior cerebellar peduncle. Together, subject-specific models provide a framework to more precisely predict pathways modulated by DBS.

  11. Common criteria among States for storage and use of dried blood spot specimens after newborn screening

    Directory of Open Access Journals (Sweden)

    Carlo Petrini

    2012-06-01

    Full Text Available Biological samples collected in biobanks are a resource with significant research potential. The Italian Joint Group cNB - cNBBSV (National committee of Bioethics - National committee for Biosecurity, Biotechnologies and Life Sciences published a document reporting recommendations on storage and use of dried blood spot (DBS and on the development of a National Network of Regional Newborn Screening Repositories for collection of residual DBS. Several ethical questions (about consent, possible use of genetic information, unanticipated possible usages for research purposes rise from residual newborn screening specimens collections. Moreover, legal and ethical controversies are accentuated by the conflicts between the interests of sample donors, biobank holders, researchers and the public. To overcome these difficulties the identification of a few criteria for storage and research usage of DBS is crucial.

  12. The Effect of Storage and Extraction Methods on Amplification of Plasmodium falciparum DNA from Dried Blood Spots

    NARCIS (Netherlands)

    Schwartz, A.; Baidjoe, A.Y.; Rosenthal, P.J.; Dorsey, G.; Bousema, T.; Greenhouse, B.

    2015-01-01

    Extraction and amplification of DNA from dried blood spots (DBS) collected in field studies is commonly used for detection of Plasmodium falciparum. However, there have been few systematic efforts to determine the effects of storage and extraction methods on the sensitivity of DNA amplification. We

  13. T2-relaxometry predicts outcome of DBS in idiopathic Parkinson's disease.

    Science.gov (United States)

    Lönnfors-Weitzel, Tarja; Weitzel, Thilo; Slotboom, Johannes; Kiefer, Claus; Pollo, Claudio; Schüpbach, Michael; Oertel, Markus; Kaelin, Alain; Wiest, Roland

    2016-01-01

    Deep brain stimulation (DBS) nowadays is a well-established treatment of motor symptoms in Parkinson's disease. The subthalamic nucleus (STN) is a common target for DBS, because motor improvements have been shown to be superior to best medical therapy, if DBS electrodes have been appropriately positioned. DBS target identification can be assisted by MRI beyond structural imaging by spatially resolved measurement of T2-relaxation times (T2r). We pose the question, whether T2r of the STN is linked to the severity of the disease and whether outcome of DBS may be correlated to an asymmetric manifestation of the disease. Further, we investigated if abnormal T2r in the STN may be predictive for outcome of DBS. Twelve patients underwent preoperative MR imaging including a multi echo relaxometry sequence (3 Tesla, Siemens Medical Systems, Erlangen, Germany) ahead of DBS. T2r were determined for STN, substantia nigra (SN), red nucleus (RN) and centrum semiovale (CSO). Unified Parkinson's disease Rating Scale (UPDRS) scores were tested before and after DBS. Patients' T2r and deduced values representing left-right asymmetry of measurements were correlated with UPDRS scores and measures for outcome of DBS. Furthermore, patients' T2r were compared with T2r measurements in 12 healthy controls (HC). Patients' T2r for SN (mean 45.4 ms ± 4.4 ms) and STN (mean 56.4 ms ± 3.8 ms) were significantly shorter than T2r in HCs for SN (mean 60.7 ± 4.6) and STN (mean 66.1 ms ± 4.0 ms). While no mean T2r asymmetry was found in the SN, patients' mean T2r for STN showed a weakened left-right correlation (Pearson correlation coefficient 0.19 versus 0.72 in HC) indicating asymmetric degeneration. T2r asymmetry was not linked to the more severely affected hemisphere. The respective lower T2r within the left or right target region was significantly correlated to the outcome in terms of UPDRS III improvement in "off" state (Pearson correlation 0.82 corresponding to p ≪ 0

  14. Three-dimensional brain MRI for DBS patients within ultra-low radiofrequency power limits.

    Science.gov (United States)

    Sarkar, Subhendra N; Papavassiliou, Efstathios; Hackney, David B; Alsop, David C; Shih, Ludy C; Madhuranthakam, Ananth J; Busse, Reed F; La Ruche, Susan; Bhadelia, Rafeeque A

    2014-04-01

    For patients with deep brain stimulators (DBS), local absorbed radiofrequency (RF) power is unknown and is much higher than what the system estimates. We developed a comprehensive, high-quality brain magnetic resonance imaging (MRI) protocol for DBS patients utilizing three-dimensional (3D) magnetic resonance sequences at very low RF power. Six patients with DBS were imaged (10 sessions) using a transmit/receive head coil at 1.5 Tesla with modified 3D sequences within ultra-low specific absorption rate (SAR) limits (0.1 W/kg) using T2 , fast fluid-attenuated inversion recovery (FLAIR) and T1 -weighted image contrast. Tissue signal and tissue contrast from the low-SAR images were subjectively and objectively compared with routine clinical images of six age-matched controls. Low-SAR images of DBS patients demonstrated tissue contrast comparable to high-SAR images and were of diagnostic quality except for slightly reduced signal. Although preliminary, we demonstrated diagnostic quality brain MRI with optimized, volumetric sequences in DBS patients within very conservative RF safety guidelines offering a greater safety margin. © 2014 International Parkinson and Movement Disorder Society.

  15. Dried Blood Spots for Measuring Vibrio cholerae-specific Immune Responses.

    Directory of Open Access Journals (Sweden)

    Anita S Iyer

    2018-01-01

    Full Text Available Vibrio cholerae causes over 2 million cases of cholera and 90,000 deaths each year. Serosurveillance can be a useful tool for estimating the intensity of cholera transmission and prioritizing populations for cholera control interventions. Current methods involving venous blood draws and downstream specimen storage and transport methods pose logistical challenges in most settings where cholera strikes. To overcome these challenges, we developed methods for determining cholera-specific immune responses from dried blood spots (DBS.As conventional vibriocidal assay methods were unsuitable for DBS eluates from filter paper, we adopted a drop-plate culture method. We show that DBS collected from volunteers in South Sudan, and stored for prolonged periods in field conditions, retained functional vibriocidal antibodies, the titers of which correlated with paired serum titers determined by conventional spectrophotometric methods (r = 0.94, p = 0.00012. We also showed that eluates from DBS Serum Separator cards could be used with conventional spectrophotometric vibriocidal methods, and that they correlated with paired serum at a wide range of titers (r = 0.96, p<0.0001. Similarly, we used ELISA methods to show that V. cholerae O-specific polysaccharide antibody responses from DBS eluates correlated with results from paired serum for IgG (r = 0.85, p = 0.00006, IgM (r = 0.79, p = 0.00049 and IgA (r = 0.73, p = 0.0019, highlighting its potential for use in determination of isotype-specific responses. Storage of DBS cards at a range of temperatures did not change antibody responses.In conclusion, we have developed and demonstrated a proof-of-concept for assays utilizing DBS for assessing cholera-specific immune responses.

  16. Comparison of cross-sectional HIV incidence assay results from dried blood spots and plasma.

    Directory of Open Access Journals (Sweden)

    Katherine E Schlusser

    Full Text Available Assays have been developed for cross-sectional HIV incidence estimation using plasma samples. Large scale surveillance programs are planned using dried blood spot (DBS specimens for incidence assessment. However, limited information exists on the performance of HIV cross-sectional incidence assays using DBS.The assays evaluated were: Maxim HIV-1 Limiting Antigen Avidity EIA (LAg-Avidity, Sedia HIV-1 BED-Capture EIA (BED-CEIA, and CDC modified BioRad HIV-1/2 Plus O Avidity-based Assay (CDC-BioRad Avidity using pre-determined cutoff values. 100 matched HIV-1 positive plasma and DBS samples, with known duration of infection, from the Consortium for the Evaluation and Performance of HIV Incidence Assays repository were tested. All assays were run in duplicate. To examine the degree of variability within and between results for each sample type, both categorical and continuous results were analyzed. Associations were assessed with Bland Altman, R2 values and Cohen's kappa coefficient (ĸ.Intra-assay variability using the same sample type was similar for all assays (R2 0.96 to 1.00. The R2 values comparing DBS and plasma results for LAg-Avidity, BED-CEIA, and CDC-BioRad Avidity were 0.96, 0.94, and 0.84, respectively. The concordance and ĸ values between DBS and plasma for all three assays were >87% and >0.64, respectively. The Bland-Altman analysis showed significant differences between plasma and DBS samples. For all three assays, a higher number of samples were classified as recent infections using DBS samples.DBS and plasma sample results were highly correlated. However, when compared to plasma, each assay performed somewhat differently in DBS at the lower and higher ends of the dynamic range. DBS samples were more likely to be classified as recently infected by all three assays, which may lead to overestimation of incidence in surveys using performance criteria derived for plasma samples.

  17. Robustness of genome-wide scanning using archived dried blood spot samples as a DNA source.

    Science.gov (United States)

    Hollegaard, Mads V; Grove, Jakob; Grauholm, Jonas; Kreiner-Møller, Eskil; Bønnelykke, Klaus; Nørgaard, Mette; Benfield, Thomas L; Nørgaard-Pedersen, Bent; Mortensen, Preben B; Mors, Ole; Sørensen, Henrik T; Harboe, Zitta B; Børglum, Anders D; Demontis, Ditte; Ørntoft, Torben F; Bisgaard, Hans; Hougaard, David M

    2011-07-04

    The search to identify disease-susceptible genes requires access to biological material from numerous well-characterized subjects. Archived residual dried blood spot (DBS) samples, also known as Guthrie cards, from national newborn screening programs may provide a DNA source for entire populations. Combined with clinical information from medical registries, DBS samples could provide a rich source for productive research. However, the amounts of DNA which can be extracted from these precious samples are minute and may be prohibitive for numerous genotypings. Previously, we demonstrated that DBS DNA can be whole-genome amplified and used for reliable genetic analysis on different platforms, including genome-wide scanning arrays. However, it remains unclear whether this approach is workable on a large sample scale. We examined the robustness of using DBS samples for whole-genome amplification following genome-wide scanning, using arrays from Illumina and Affymetrix. This study is based on 4,641 DBS samples from the Danish Newborn Screening Biobank, extracted for three separate genome-wide association studies. The amount of amplified DNA was significantly (P Biobank represent a reliable resource of DNA for whole-genome amplification and subsequent genome-wide association studies. With call-rates equivalent to high quality DNA samples, our results point to new opportunities for using the neonatal biobanks available worldwide in the hunt for genetic components of disease.

  18. Enhancement of the photocatalytic activity of TiO2 nanoparticles by surface-capping DBS groups

    International Nuclear Information System (INIS)

    Wang Baiqi; Jing Liqiang; Qu Yichun; Li Shudan; Jiang Baojiang; Yang Libin; Xin Baifu; Fu Honggang

    2006-01-01

    TiO 2 nanoparticles capped with sodium dodecylbenzenesulfonate (DBS) are synthesized by a sol-hydrothermal process using tetrabutyl titanate and DBS as raw materials. The effects of surface-capping DBS on the surface photovoltage spectroscopy (SPS), photoluminescence (PL) and photocatalytic performance of TiO 2 nanoparticles are principally investigated together with their relationships. The results show that the surface of TiO 2 nanoparticles can be well capped by DBS groups while the pH value and added DBS amount are controlled at 5.0 and 2% of TiO 2 mass weight, respectively, and the linkage between DBS groups and TiO 2 surfaces is mainly by means of quasi-sulphonate bond. The intensities of SPS and PL spectra of TiO 2 obviously decrease after DBS-capping, while the activity can greatly increase during the photocatalytic degradation of Rhodamine B (RhB) solution, which are mainly attributed to the electron-withdrawing character of the DBS groups. Moreover, the enhancement of photocatalytic activity of DBS-capped TiO 2 is also related to the increase in the capability for adsorbing RhB

  19. Quantification of rifapentine, a potent antituberculosis drug, from dried blood spot samples using liquid chromatographic-tandem mass spectrometric analysis.

    Science.gov (United States)

    Parsons, Teresa L; Marzinke, Mark A; Hoang, Thuy; Bliven-Sizemore, Erin; Weiner, Marc; Mac Kenzie, William R; Dorman, Susan E; Dooley, Kelly E

    2014-11-01

    The quantification of antituberculosis drug concentrations in multinational trials currently requires the collection of modest blood volumes, centrifugation, aliquoting of plasma, freezing, and keeping samples frozen during shipping. We prospectively enrolled healthy individuals into the Tuberculosis Trials Consortium Study 29B, a phase I dose escalation study of rifapentine, a rifamycin under evaluation in tuberculosis treatment trials. We developed a liquid chromatography-tandem mass spectrometry (LC-MS/MS) method for quantifying rifapentine in whole blood on dried blood spots (DBS) to facilitate pharmacokinetic/pharmacodynamic analyses in clinical trials. Paired plasma and whole-blood samples were collected by venipuncture, and whole blood was spotted on Whatman protein saver 903 cards. The methods were optimized for plasma and then validated for DBS. The analytical measuring range for quantification of rifapentine and its metabolite was 50 to 80,000 ng/ml in whole-blood DBS. The analyte was stable on the cards for 11 weeks with a desiccant at room temperature and protected from light. The method concordance for paired plasma and whole-blood DBS samples was determined after correcting for participant hematocrit or population-based estimates of bias from Bland-Altman plots. The application of either correction factor resulted in acceptable correlation between plasma and whole-blood DBS (Passing-Bablok regression corrected for hematocrit; y = 0.98x + 356). Concentrations of rifapentine may be determined from whole-blood DBS collected via venipuncture after normalization in order to account for the dilutional effects of red blood cells. Additional studies are focused on the application of this methodology to capillary blood collected by finger stick. The simplicity of processing, storage, shipping, and low blood volume makes whole-blood DBS attractive for rifapentine pharmacokinetic evaluations, especially in international and pediatric trials. Copyright © 2014

  20. Automated DBS microsampling, microscale automation and microflow LC-MS for therapeutic protein PK.

    Science.gov (United States)

    Zhang, Qian; Tomazela, Daniela; Vasicek, Lisa A; Spellman, Daniel S; Beaumont, Maribel; Shyong, BaoJen; Kenny, Jacqueline; Fauty, Scott; Fillgrove, Kerry; Harrelson, Jane; Bateman, Kevin P

    2016-04-01

    Reduce animal usage for discovery-stage PK studies for biologics programs using microsampling-based approaches and microscale LC-MS. We report the development of an automated DBS-based serial microsampling approach for studying the PK of therapeutic proteins in mice. Automated sample preparation and microflow LC-MS were used to enable assay miniaturization and improve overall assay throughput. Serial sampling of mice was possible over the full 21-day study period with the first six time points over 24 h being collected using automated DBS sample collection. Overall, this approach demonstrated comparable data to a previous study using single mice per time point liquid samples while reducing animal and compound requirements by 14-fold. Reduction in animals and drug material is enabled by the use of automated serial DBS microsampling for mice studies in discovery-stage studies of protein therapeutics.

  1. Deep brain stimulation (DBS) at the interface of neurology and psychiatry

    Science.gov (United States)

    Williams, Nolan R.; Okun, Michael S.

    2013-01-01

    Deep brain stimulation (DBS) is an emerging interventional therapy for well-screened patients with specific treatment-resistant neuropsychiatric diseases. Some neuropsychiatric conditions, such as Parkinson disease, have available and reasonable guideline and efficacy data, while other conditions, such as major depressive disorder and Tourette syndrome, have more limited, but promising results. This review summarizes both the efficacy and the neuroanatomical targets for DBS in four common neuropsychiatric conditions: Parkinson disease, Tourette syndrome, major depressive disorder, and obsessive-compulsive disorder. Based on emerging new research, we summarize novel approaches to optimization of stimulation for each neuropsychiatric disease and we review the potential positive and negative effects that may be observed following DBS. Finally, we summarize the likely future innovations in the field of electrical neural-network modulation. PMID:24177464

  2. Dried Blood Spot Reference Intervals for Steroids and Amino Acids in a Neonatal Cohort of the National Children's Study.

    Science.gov (United States)

    Dietzen, Dennis J; Bennett, Michael J; Lo, Stanley F; Grey, Vijay L; Jones, Patti M

    2016-12-01

    Reference intervals from children are limited by access to healthy children and their limited blood volumes. In this study we set out to fill gaps in pediatric reference intervals for amino acids and steroid hormones using dried blood spots (DBS) from a cohort of the National Children's Study. Deidentified DBS annotated with age, birthweight, sex, and geographic location were obtained from 310 newborns aged 0-4 days and analyzed for 25 amino acids and 4 steroid hormones using LC-MS/MS. Nonparametric statistical approaches were used to generate the 2.5th-97.5th percentile distributions for newborns. Paired plasma/DBS specimens were used to mathematically transform DBS reference intervals to corresponding plasma intervals. 10 of 25 DBS amino acid distributions were dependent on sex. There was little correlation with age, birthweight, or geographic location over the first 4 days of life. In most cases, transformation of DBS distributions to plasma distributions faithfully reflected independent studies of newborn plasma amino acid distributions. In general newborn steroid distributions were negatively correlated with age and birthweight over the first 4 days of life. Data distributions for the 4 steroids were not found related to geographic location, but testosterone concentrations displayed sex dependence. Transformation of DBS distributions to plasma intervals did not faithfully replicate other neonate steroid reference intervals determined directly with plasma. These data demonstrate the feasibility and utility of deriving newborn reference intervals from large numbers of archived DBS samples such as those obtained from the National Children's Study biobank. © 2016 American Association for Clinical Chemistry.

  3. Newborn Dried Blood Spot Polymerase Chain Reaction to Identify Infants with Congenital Cytomegalovirus-Associated Sensorineural Hearing Loss.

    Science.gov (United States)

    Ross, Shannon A; Ahmed, Amina; Palmer, April L; Michaels, Marian G; Sánchez, Pablo J; Stewart, Audra; Bernstein, David I; Feja, Kristina; Fowler, Karen B; Boppana, Suresh B

    2017-05-01

    To determine the utility of dried blood spot (DBS) polymerase chain reaction (PCR) in identifying infants with cytomegalovirus (CMV) infection-associated sensorineural hearing loss (SNHL). Newborns at 7 US hospitals between March 2007 and March 2012 were screened for CMV by saliva rapid culture and/or PCR. Infected infants were monitored for SNHL during the first 4 years of life to determine sensitivity, specificity, and positive and negative likelihood ratios of DBS PCR for identifying CMV-associated SNHL. DBS at birth was positive in 11 of 26 children (42%) with SNHL at age 4 years and in 72 of 270 children (27%) with normal hearing (P = .11). The sensitivity (42.3%; 95% CI, 23.4%-63.1%) and specificity (73.3%; 95% CI, 67.6%-78.5%) was low for DBS PCR in identifying children with SNHL at age 4 years. The positive and negative likelihood ratios of DBS PCR positivity to detect CMV-associated SNHL at age 4 years were 1.6 (95% CI, 0.97-2.6) and 0.8 (95% CI, 0.6-1.1), respectively. There was no difference in DBS viral loads between children with SNHL and those without SNHL. DBS PCR for CMV has low sensitivity and specificity for identifying infants with CMV-associated hearing loss. These findings, together with previous reports, demonstrate that DBS PCR does not identify either the majority of CMV-infected newborns or those with CMV-associated SNHL early in life. Copyright © 2017 Elsevier Inc. All rights reserved.

  4. Using STN DBS and medication reduction as a strategy to treat pathological gambling in Parkinson's disease.

    Science.gov (United States)

    Bandini, Fabio; Primavera, Alberto; Pizzorno, Matteo; Cocito, Leonardo

    2007-08-01

    We describe two patients with Parkinson's disease (PD) who developed clinical criteria of pathological gambling addiction in the setting of increased dopamine replacement therapy (levodopa and dopamine agonist medications). The second patient showed also signs of dopamine dysregulation syndrome, with an addiction to dopaminergic medication. Neither patients responded to the standard therapy for gambling behavior, but dramatically improved after bilateral subthalamic nucleus (STN) deep brain stimulation (DBS) and early postoperative withdrawal of dopaminergic therapy. The possible therapeutic role of subthalamic nucleus deep brain stimulation (STN-DBS) on such a disabling behavior needs to be investigated prospectively.

  5. Electrochemical Behaviour of a PPy(DBS)/Polyacrylonitrile (PAN):LITF:EC:PC/ Li Cell

    DEFF Research Database (Denmark)

    Vidanapathirana, K.; Careem, M.A.; Skaarup, Steen

    2006-01-01

    The electrochemical behaviour of Li rechargeable cells with Polypyrrole (PPy) as the cathode material was investigated using cyclic voltammetry. The PPy used was doped with the large surfactant anion dodecyl benzenesulphonate (DBS-). The cells were constructed with PAN:LiTF:EC:PC gel electrolyte...... with Li as anode. The results indicate that during the first reduction, cations are inserted into the PPy film forming LiDBS neutral salt. During the next oxidation/reduction cycles, the mechanism then switches to anion movement. Cyclic voltammetry studies also verified that complete electrochemical...

  6. Screening for HIV, hepatitis B and syphilis on dried blood spots: A promising method to better reach hidden high-risk populations with self-collected sampling.

    Directory of Open Access Journals (Sweden)

    Inge H M van Loo

    Full Text Available Many people at high risk for sexually transmitted infections (STIs, e.g., men who have sex with men (MSM, are not optimally reached by current sexual health care systems with testing. To facilitate testing by home-based sampling or sampling in outreach setting we evaluated dried blood spots (DBS, a method for self-collected blood sampling for serological screening of HIV, hepatitis B (HBV and syphilis. The aims of this study were to assess the acceptability and feasibility of self-collected DBS and to compare the test results for screening of HIV, HBV and syphilis from DBS with blood drawn by venous puncture.DBS were collected from men who have sex with men (MSM, visiting the STI clinic of the public health service South Limburg (n = 183 and HIV positive and HBV positive patients (n = 34, visiting the outpatient clinics of the Maastricht University Medical Centre in the period January 2012-April 2015. The 93 first participating MSM visiting the STI clinic were asked to fill in a questionnaire about the feasibility and acceptability about self-collection of DBS in a setting without going to a health care facility and were asked to collect the DBS themselves. Serological screening tests for HIV (HIV combi PT, Roche, HBV (HBsAg, Roche and syphilis (Treponema pallidum Ig, Biokit 3.0 were performed on DBS and on blood drawn by venous puncture, which was routinely taken for screening.In total 217 participants were included in the study with a median age of 40 years (range between 17-80. Of MSM 84% agreed that it was clear and easy to do the finger-prick, while 53% agreed that it was clear and easy to apply the blood onto the DBS card. Also, 80% of MSM would use the bloodspot test again. In 91% (198 of DBS, sufficient material was collected to perform the three tests. No difference was observed in DBS quality between self-collected DBS and health care worker collected DBS. For HIV (n = 195 DBS-serum pairs sensitivity and specificity were 100%. For HBV

  7. Dried Blood Spots, an Affordable Tool to Collect, Ship, and Sequence gDNA from Patients with an X-Linked Agammaglobulinemia Phenotype Residing in a Developing Country

    Directory of Open Access Journals (Sweden)

    Gesmar R. S. Segundo

    2018-02-01

    Full Text Available BackgroundNew sequencing techniques have revolutionized the identification of the molecular basis of primary immunodeficiency disorders (PID not only by establishing a gene-based diagnosis but also by facilitating defect-specific treatment strategies, improving quality of life and survival, and allowing factual genetic counseling. Because these techniques are generally not available for physicians and their patients residing in developing countries, collaboration with overseas laboratories has been explored as a possible, albeit cumbersome, strategy. To reduce the cost of time and temperature-sensitive shipping, we selected Guthrie cards, developed for newborn screening, to collect dried blood spots (DBS, as a source of DNA that can be shipped by regular mail at minimal cost.MethodBlood was collected and blotted onto the filter paper of Guthrie cards by completely filling three circles. We enrolled 20 male patients with presumptive X-linked agammaglobulinemia (XLA cared for at the Vietnam National Children’s Hospital, their mothers, and several sisters for carrier analysis. DBS were stored at room temperature until ready to be shipped together, using an appropriately sized envelope, to a CLIA-certified laboratory in the US for sequencing. The protocol for Sanger sequencing was modified to account for the reduced quantity of gDNA extracted from DBS.ResultHigh-quality gDNA could be extracted from every specimen. Bruton tyrosine kinase (BTK mutations were identified in 17 of 20 patients studied, confirming the diagnosis of XLA in 85% of the study cohort. Type and location of the mutations were similar to those reported in previous reviews. The mean age when XLA was suspected clinically was 4.6 years, similar to that reported by Western countries. Two of 15 mothers, each with an affected boy, had a normal BTK sequence, suggesting gonadal mosaicism.ConclusionDBS collected on Guthrie cards can be shipped inexpensively by airmail across continents

  8. Prediction of STN-DBS Electrode Implantation Track in Parkinson’s Disease by Using Local Field Potentials

    Directory of Open Access Journals (Sweden)

    Ilknur eTelkes

    2016-05-01

    Full Text Available Optimal electrophysiological placement of the DBS electrode may lead to better long term clinical outcomes. Inter-subject anatomical variability and limitations in stereotaxic neuroimaging increase the complexity of physiological mapping performed in the operating room. Microelectrode single unit neuronal recording remains the most common intraoperative mapping technique, but requires significant expertise and is fraught by potential technical difficulties including robust measurement of the signal. In contrast, local field potentials (LFPs, owing to their oscillatory and robust nature and being more correlated with the disease symptoms, can overcome these technical issues. Therefore, we hypothesized that multiple spectral features extracted from microelectrode-recorded LFPs could be used to automate the identification of the optimal track and the STN localization. In this regard, we recorded LFPs from microelectrodes in three tracks from 22 patients during DBS electrode implantation surgery at different depths and aimed to predict the track selected by the neurosurgeon based on the interpretation of single unit recordings. A least mean square (LMS algorithm was used to de-correlate LFPs in each track, in order to remove common activity between channels and increase their spatial specificity. Subband power in the beta band (11-32Hz and high frequency range (200-450Hz were extracted from the de-correlated LFP data and used as features. A linear discriminant analysis (LDA method was applied both for the localization of the dorsal border of STN and the prediction of the optimal track. By fusing the information from these low and high frequency bands, the dorsal border of STN was localized with a root mean square error of 1.22 mm. The prediction accuracy for the optimal track was 80%. Individual beta band (11-32Hz and the range of high frequency oscillations (200-450Hz provided prediction accuracies of 72% and 68% respectively. The best prediction

  9. Prenatal Education of Parents About Newborn Screening and Residual Dried Blood Spots: A Randomized Clinical Trial.

    Science.gov (United States)

    Botkin, Jeffrey R; Rothwell, Erin; Anderson, Rebecca A; Rose, Nancy C; Dolan, Siobhan M; Kuppermann, Miriam; Stark, Louisa A; Goldenberg, Aaron; Wong, Bob

    2016-06-01

    Research clearly indicates that current approaches to newborn blood spot screening (NBS) education are ineffective. Incorporating NBS education into prenatal care is broadly supported by lay and professional opinion. To determine the efficacy and effect of prenatal education about newborn screening and use of residual dried blood spots (DBS) in research on parental knowledge, attitudes, and behaviors. A randomized clinical trial of prenatal educational interventions, with outcomes measured by survey at 2 to 4 weeks postpartum. Participants were recruited from obstetric clinics in Salt Lake City, Utah; San Francisco, California; and the Bronx, New York. Eligible women were English- or Spanish-speaking adults and did not have a high-risk pregnancy. A total of 901 women were enrolled. Participants who completed the follow-up survey included 212 women in the usual care group (70% retention), 231 in the NBS group (77% retention), and 221 women in the NBS + DBS group (75% retention). Those who completed the survey were similar across the 3 groups with respect to age, ethnicity, race, education, marital status, income, obstetric history, and language. Participants were randomized into 1 of 3 groups: usual care (n = 305), those viewing an NBS movie and brochure (n = 300), and those viewing both the NBS and DBS movies and brochures (n = 296). Two to four weeks postpartum, women completed a 91-item survey by telephone, addressing knowledge, attitudes, and behavior with respect to opting out of NBS or DBS for their child. A total of 901 women (mean age, 31 years) were randomized and 664 completed the follow-up survey. The total correct responses on the knowledge instrument in regard to NBS were 69% in the usual care group, 79% in the NBS group, and 75% in the NBS + DBS group, a significant between-group difference (P women who were "very supportive" was highest in the NBS group (94%), followed by the NBS + DBS group (86%) and was lowest in the usual care

  10. Faculty Perceptions of Loughborough's Online Reading List System (LORLS) at Dublin Business School (DBS)

    Science.gov (United States)

    O'Neill, Marie; Musto, Lara

    2017-01-01

    Using a mixed methods research approach this study explores faculty perceptions of LORLS at DBS. Data generated by the study will inform advocacy, marketing and training initiatives to promote the platform. The study concludes with a number of deductive and inductive findings. The first is that although DBS faculty are highly predisposed to using…

  11. Targeted neural network interventions for auditory hallucinations: Can TMS inform DBS?

    Science.gov (United States)

    Taylor, Joseph J; Krystal, John H; D'Souza, Deepak C; Gerrard, Jason Lee; Corlett, Philip R

    2017-09-29

    The debilitating and refractory nature of auditory hallucinations (AH) in schizophrenia and other psychiatric disorders has stimulated investigations into neuromodulatory interventions that target the aberrant neural networks associated with them. Internal or invasive forms of brain stimulation such as deep brain stimulation (DBS) are currently being explored for treatment-refractory schizophrenia. The process of developing and implementing DBS is limited by symptom clustering within psychiatric constructs as well as a scarcity of causal tools with which to predict response, refine targeting or guide clinical decisions. Transcranial magnetic stimulation (TMS), an external or non-invasive form of brain stimulation, has shown some promise as a therapeutic intervention for AH but remains relatively underutilized as an investigational probe of clinically relevant neural networks. In this editorial, we propose that TMS has the potential to inform DBS by adding individualized causal evidence to an evaluation processes otherwise devoid of it in patients. Although there are significant limitations and safety concerns regarding DBS, the combination of TMS with computational modeling of neuroimaging and neurophysiological data could provide critical insights into more robust and adaptable network modulation. Copyright © 2017 Elsevier B.V. All rights reserved.

  12. EFFECT OF MOLECULAR ARCHITECTURE ON DBS-INDUCED BLOCK COPOLYMER GELS: A RHEOLOGICAL STUDY

    Science.gov (United States)

    Dibenzylidene sorbitol (DBS) is capable of gelling a variety of organic solvents and polymeric materials by forming a rigid, 3-D hydrogen-bonded network. In this work, two poly(siloxane)/poly(propylene oxide) segmented copolymers of equal composition and molecular weight, but di...

  13. MDS-UPDRS to assess non-motor symptoms after STN DBS for Parkinson's disease.

    Science.gov (United States)

    Jafari, Nickey; Pahwa, Rajesh; Nazzaro, Jules M; Arnold, Paul M; Lyons, Kelly E

    2016-01-01

    To determine if the non-motor sections of the Movement Disorder Society's (MDS) version of the Unified Parkinson's Disease Rating Scale (UPDRS) could supplement the original UPDRS as a patient completed assessment of changes in non-motor symptoms in Parkinson's disease (PD) patients after bilateral subthalamic nucleus (STN) deep brain stimulation (DBS). Thirty PD patients who underwent bilateral STN DBS were assessed using the total UPDRS and the non-motor sections of the MDS-UPDRS prior to surgery and one year following surgery. This study focuses on non-motor symptoms as assessed by Part I of the UPDRS and Part 1A and 1B of the MDS-UPDRS. One year following surgery, no individual non-motor symptoms or the total mentation score of the UPDRS were significantly changed. In comparison, the MDS-UPDRS showed significant improvements in sleep and urinary problems and a trend towards improvement in anxiety, constipation, daytime sleepiness, fatigue and pain. This study provides evidence that the MDS-UPDRS non-motor sections, when completed by the patients, can supplement the original version of the UPDRS as an effective method of measuring changes in non-motor symptoms after DBS. It also reinforces the benefits of bilateral STN DBS on non-motor symptoms of PD.

  14. MRI-Based Multiscale Model for Electromagnetic Analysis in the Human Head with Implanted DBS

    Directory of Open Access Journals (Sweden)

    Maria Ida Iacono

    2013-01-01

    Full Text Available Deep brain stimulation (DBS is an established procedure for the treatment of movement and affective disorders. Patients with DBS may benefit from magnetic resonance imaging (MRI to evaluate injuries or comorbidities. However, the MRI radio-frequency (RF energy may cause excessive tissue heating particularly near the electrode. This paper studies how the accuracy of numerical modeling of the RF field inside a DBS patient varies with spatial resolution and corresponding anatomical detail of the volume surrounding the electrodes. A multiscale model (MS was created by an atlas-based segmentation using a 1 mm3 head model (mRes refined in the basal ganglia by a 200 μm2 ex-vivo dataset. Four DBS electrodes targeting the left globus pallidus internus were modeled. Electromagnetic simulations at 128 MHz showed that the peak of the electric field of the MS doubled (18.7 kV/m versus 9.33 kV/m and shifted 6.4 mm compared to the mRes model. Additionally, the MS had a sixfold increase over the mRes model in peak-specific absorption rate (SAR of 43.9 kW/kg versus 7 kW/kg. The results suggest that submillimetric resolution and improved anatomical detail in the model may increase the accuracy of computed electric field and local SAR around the tip of the implant.

  15. Effect of Deep Brain Stimulation on Parkinson's Nonmotor Symptoms following Unilateral DBS: A Pilot Study

    Directory of Open Access Journals (Sweden)

    Nelson Hwynn

    2011-01-01

    Full Text Available Parkinson’s disease (PD management has traditionally focused largely on motor symptoms. Deep brain stimulation (DBS of the subthalamic nucleus (STN and globus pallidus internus (GPi are effective treatments for motor symptoms. Nonmotor symptoms (NMSs may also profoundly affect the quality of life. The purpose of this pilot study was to evaluate NMS changes pre- and post-DBS utilizing two recently developed questionnaires. Methods. NMS-Q (questionnaire and NMS-S (scale were administered to PD patients before/after unilateral DBS (STN/GPi targets. Results. Ten PD patients (9 STN implants, 1 GPi implant were included. The three most frequent NMS symptoms identified utilizing NMS-Q in pre-surgical patients were gastrointestinal (100%, sleep (100%, and urinary (90%. NMS sleep subscore significantly decreased (−1.6 points ± 1.8, =0.03. The three most frequent NMS symptoms identified in pre-surgical patients using NMS-S were gastrointestinal (90%, mood (80%, and cardiovascular (80%. The largest mean decrease of NMS scores was seen in miscellaneous symptoms (pain, anosmia, weight change, and sweating (−7 points ± 8.7, and cardiovascular/falls (−1.9, =0.02. Conclusion. Non-motor symptoms improved on two separate questionnaires following unilateral DBS for PD. Future studies are needed to confirm these findings and determine their clinical significance as well as to examine the strengths/weaknesses of each questionnaire/scale.

  16. Energy dispersive X-ray fluorescence spectrometry for the direct multi-element analysis of dried blood spots

    Science.gov (United States)

    Marguí, E.; Queralt, I.; García-Ruiz, E.; García-González, E.; Rello, L.; Resano, M.

    2018-01-01

    Home-based collection protocols for clinical specimens are actively pursued as a means of improving life quality of patients. In this sense, dried blood spots (DBS) are proposed as a non-invasive and even self-administered alternative to sampling whole venous blood. This contribution explores the potential of energy dispersive X-ray fluorescence spectrometry for the simultaneous and direct determination of some major (S, Cl, K, Na), minor (P, Fe) and trace (Ca, Cu, Zn) elements in blood, after its deposition onto clinical filter papers, thus giving rise to DBS. For quantification purposes the best strategy was to use matrix-matched blood samples of known analyte concentrations. The accuracy and precision of the method were evaluated by analysis of a blood reference material (Seronorm™ trace elements whole blood L3). Quantitative results were obtained for the determination of P, S, Cl, K and Fe, and limits of detection for these elements were adequate, taking into account their typical concentrations in real blood samples. Determination of Na, Ca, Cu and Zn was hampered by the occurrence of high sample support (Na, Ca) and instrumental blanks (Cu, Zn). Therefore, the quantitative determination of these elements at the levels expected in blood samples was not feasible. The methodology developed was applied to the analysis of several blood samples and the results obtained were compared with those reported by standard techniques. Overall, the performance of the method developed is promising and it could be used to determine the aforementioned elements in blood samples in a simple, fast and economic way. Furthermore, its non-destructive nature enables further analyses by means of complementary techniques to be carried out.

  17. High-Quality Exome Sequencing of Whole-Genome Amplified Neonatal Dried Blood Spot DNA.

    Directory of Open Access Journals (Sweden)

    Jesper Buchhave Poulsen

    Full Text Available Stored neonatal dried blood spot (DBS samples from neonatal screening programmes are a valuable diagnostic and research resource. Combined with information from national health registries they can be used in population-based studies of genetic diseases. DNA extracted from neonatal DBSs can be amplified to obtain micrograms of an otherwise limited resource, referred to as whole-genome amplified DNA (wgaDNA. Here we investigate the robustness of exome sequencing of wgaDNA of neonatal DBS samples. We conducted three pilot studies of seven, eight and seven subjects, respectively. For each subject we analysed a neonatal DBS sample and corresponding adult whole-blood (WB reference sample. Different DNA sample types were prepared for each of the subjects. Pilot 1: wgaDNA of 2x3.2mm neonatal DBSs (DBS_2x3.2 and raw DNA extract of the WB reference sample (WB_ref. Pilot 2: DBS_2x3.2, WB_ref and a WB_ref replica sharing DNA extract with the WB_ref sample. Pilot 3: DBS_2x3.2, WB_ref, wgaDNA of 2x1.6 mm neonatal DBSs and wgaDNA of the WB reference sample. Following sequencing and data analysis, we compared pairwise variant calls to obtain a measure of similarity--the concordance rate. Concordance rates were slightly lower when comparing DBS vs WB sample types than for any two WB sample types of the same subject before filtering of the variant calls. The overall concordance rates were dependent on the variant type, with SNPs performing best. Post-filtering, the comparisons of DBS vs WB and WB vs WB sample types yielded similar concordance rates, with values close to 100%. WgaDNA of neonatal DBS samples performs with great accuracy and efficiency in exome sequencing. The wgaDNA performed similarly to matched high-quality reference--whole-blood DNA--based on concordance rates calculated from variant calls. No differences were observed substituting 2x3.2 with 2x1.6 mm discs, allowing for additional reduction of sample material in future projects.

  18. Individualized current-shaping reduces DBS-induced dysarthria in patients with essential tremor.

    Science.gov (United States)

    Barbe, Michael T; Dembek, Till A; Becker, Johannes; Raethjen, Jan; Hartinger, Mariam; Meister, Ingo G; Runge, Matthias; Maarouf, Mohammad; Fink, Gereon R; Timmermann, Lars

    2014-02-18

    To investigate in patients with essential tremor (ET) treated with thalamic/subthalamic deep brain stimulation (DBS) whether stimulation-induced dysarthria (SID) can be diminished by individualized current-shaping with interleaving stimulation (cs-ILS) while maintaining tremor suppression (TS). Of 26 patients screened, 10 reported SID and were invited for testing. TS was assessed by the Tremor Rating Scale and kinematic analysis of postural and action tremor. SID was assessed by phonetic and logopedic means. Additionally, patients rated their dysarthria on a visual analog scale. In 6 of the 10 patients with ET, DBS-ON (relative to DBS-OFF) led to SID while tremor was successfully reduced. When comparing individualized cs-ILS with a non-current-shaped interleaving stimulation (ILS) in these patients, there was no difference in TS while 4 of the 6 patients showed subjective improvement of speech during cs-ILS. Phonetic analysis (ILS vs cs-ILS) revealed that during cs-ILS there was a reduction of voicing during the production of voiceless stop consonants and also a trend toward an improvement in oral diadochokinetic rate, reflecting less dysarthria. Logopedic rating showed a trend toward deterioration in the diadochokinesis task when comparing ON with OFF but no difference between ILS and cs-ILS. This is a proof-of-principle evaluation of current-shaping in patients with ET treated with thalamic/subthalamic DBS and experiencing SID. Data suggest a benefit on SID from individual shaping of current spread while TS is preserved. This study provides Class IV evidence that in patients with ET treated with DBS with SID, individualized cs-ILS reduces dysarthria while maintaining tremor control.

  19. Fully automated drug screening of dried blood spots using online LC-MS/MS analysis

    Directory of Open Access Journals (Sweden)

    Stefan Gaugler

    2018-01-01

    Full Text Available A new and fully automated workflow for the cost effective drug screening of large populations based on the dried blood spot (DBS technology was introduced in this study. DBS were prepared by spotting 15 μL of whole blood, previously spiked with alprazolam, amphetamine, cocaine, codeine, diazepam, fentanyl, lysergic acid diethylamide (LSD, 3,4-methylenedioxymethamphet-amine (MDMA, methadone, methamphetamine, morphine and oxycodone onto filter paper cards. The dried spots were scanned, spiked with deuterated standards and directly extracted. The extract was transferred online to an analytical LC column and then to the electrospray ionization tandem mass spectrometry system. All drugs were quantified at their cut-off level and good precision and correlation within the calibration range was obtained. The method was finally applied to DBS samples from two patients with back pain and codeine and oxycodone could be identified and quantified accurately below the level of misuse of 89.6 ng/mL and 39.6 ng/mL respectively.

  20. The development and validation of dried blood spots for external quality assurance of syphilis serology

    Directory of Open Access Journals (Sweden)

    Smit Pieter W

    2013-02-01

    Full Text Available Abstract Background Syphilis causes up to 1,500,000 congenital syphilis cases annually. These could be prevented if all pregnant women were screened, and those with syphilis treated with a single dose of penicillin before 28 weeks gestation. In recent years, rapid point-of-care tests have allowed greater access to syphilis screening, especially in rural or remote areas, but the lack of quality assurance of rapid testing has been a concern. We determined the feasibility of using dried blood spots (DBS as specimens for quality assurance of syphilis serological assays. Methods We developed DBS extraction protocols for use with Treponema pallidum particle agglutination assay (TPPA, Treponema pallidum haemagglutination assay (TPHA and an enzyme immunoassay (EIA and compared the results with those using matching plasma samples from the same patient. Results Since DBS samples showed poor performance with TPHA and EIA (TPHA sensitivity was 50.5% (95% confidence interval: 39.9–61.2% and EIA specificity was 50.4% (95% CI: 43.7–57.1%, only the DBS TPPA was used in the final evaluation. DBS TPPA showed an sensitivity of 95.5% (95% CI: 91.3–98.0% and a specificity of 99.0% (95% CI: 98.1–99.5% compared to TPPA using plasma samples as a reference. Conclusion DBS samples can be recommended for use with TPPA, and may be of value for external quality assurance of point-of-care syphilis testing.

  1. SpotADAPT

    DEFF Research Database (Denmark)

    Kaulakiene, Dalia; Thomsen, Christian; Pedersen, Torben Bach

    2015-01-01

    by Amazon Web Services (AWS). The users aiming for the spot market are presented with many instance types placed in multiple datacenters in the world, and thus it is difficult to choose the optimal deployment. In this paper, we propose the framework SpotADAPT (Spot-Aware (re-)Deployment of Analytical...... execution within boundaries). Moreover, during the execution of the workload, SpotADAPT suggests a redeployment if the current spot instance gets terminated by Amazon or a better deployment becomes possible due to fluctuations of the spot prices. The approach is evaluated using the actual execution times...

  2. Next-generation sequencing of dried blood spot specimens: a novel approach to HIV drug-resistance surveillance.

    Science.gov (United States)

    Ji, Hezhao; Li, Yang; Graham, Morag; Liang, Ben Binhua; Pilon, Richard; Tyson, Shari; Peters, Geoff; Tyler, Shaun; Merks, Harriet; Bertagnolio, Silvia; Soto-Ramirez, Luis; Sandstrom, Paul; Brooks, James

    2011-01-01

    HIV drug-resistance (DR) surveillance in resource-limited settings can be performed using dried blood spots (DBS) because of ease of collection, transportation and storage. Analysis of pooled specimens on next-generation sequencing (NGS)-based platforms, such as the 454 pyrosequencing, is an efficient sequencing method for determining HIV DR rates. In this study, we conducted HIV DR surveillance on DBS using NGS and identified minority variants in individual patients. A total of 48 extracts of DBS from an HIV DR surveillance study in Mexico City were re-amplified using primers tagged with multiplex identifiers, pooled and pyrosequenced. Consensus sequences were generated for each specimen with mixtures identified at positions where >20% of the reads contained a variant. Individual consensus sequences were then analysed for DR mutations and compared with those derived from Sanger sequencing. DBS analysed with tagged pooled pyrosequencing (TPP) were highly concordant with Sanger sequencing genotypes from matching plasma and DBS (99.21% and 99.51%, respectively). An exception was an M184I mutation only detected with TPP of DBS at a frequency of 20.4%. Multiple specimens had minority variant reads below the 20% mixture threshold. TPP using DBS is an effective method for HIV DR surveillance. TPP for genotyping results in cost savings of 40% over conventional in-house methods. The effect of low-abundance DR mutations, undetectable by conventional methods, remains to be determined. This technology might be applied to any HIV specimen (plasma/serum) and can also be used for other diagnostic assays where DNA sequencing is required. © 2011 International Medical Press

  3. Technical Stability and Biological Variability in MicroRNAs from Dried Blood Spots: A Lung Cancer Therapy-Monitoring Showcase.

    Science.gov (United States)

    Kahraman, Mustafa; Laufer, Thomas; Backes, Christina; Schrörs, Hannah; Fehlmann, Tobias; Ludwig, Nicole; Kohlhaas, Jochen; Meese, Eckart; Wehler, Thomas; Bals, Robert; Keller, Andreas

    2017-09-01

    Different work flows have been proposed to use miRNAs as blood-borne biomarkers. In particular, the method used for collecting blood from patients can considerably influence the diagnostic results. We explored whether dried blood spots (DBSs) facilitate stable miRNA measurements and compared its technical stability with biological variability. First, we tested the stability of DBS samples by generating from 1 person 18 whole-genome-wide miRNA profiles of DBS samples that were exposed to different temperature and humidity conditions. Second, we investigated technical reproducibility by performing 7 replicates of DBS again from 1 person. Third, we investigated DBS samples from 53 patients with lung cancer undergoing different therapies. Across these 3 stages, 108 genome-wide miRNA profiles from DBS were generated and evaluated biostatistically. In the stability analysis, we observed that temperature and humidity had an overall limited influence on the miRNomes (average correlation between the different conditions of 0.993). Usage of a silica gel slightly diminished DBS' technical reproducibility. The 7 technical replicates had an average correlation of 0.996. The correlation with whole-blood PAXGene miRNomes of the same individual was remarkable (correlation of 0.88). Finally, evaluation of the samples from the 53 patients with lung cancer exposed to different therapies showed that the biological variations exceeded the technical variability significantly ( P technical variations significantly. DBS-based miRNA profiles will potentially further the translational character of miRNA biomarker studies. © 2017 American Association for Clinical Chemistry.

  4. Suicide ideation and behaviours after STN and GPi DBS surgery for Parkinson's disease: results from a randomised, controlled trial.

    Science.gov (United States)

    Weintraub, Daniel; Duda, John E; Carlson, Kimberly; Luo, Ping; Sagher, Oren; Stern, Matthew; Follett, Kenneth A; Reda, Domenic; Weaver, Frances M

    2013-10-01

    The risk of suicide behaviours post-deep brain stimulation (DBS) surgery in Parkinson's disease (PD) remains controversial. We assessed if suicide ideation and behaviours are more common in PD patients (1) randomised to DBS surgery versus best medical therapy (BMT); and (2) randomised to subthalamic nucleus (STN) versus globus pallidus interna (GPi) DBS surgery. In Phase 1 of the Veterans Affairs CSP 468 study, 255 PD patients were randomised to DBS surgery (n=121) or 6 months of BMT (n=134). For Phase 2, a total of 299 patients were randomised to STN (n=147) or GPi (n=152) DBS surgery. Patients were assessed serially with the Unified Parkinson's Disease Rating Scale Part I depression item, which queries for suicide ideation; additionally, both suicide behaviour adverse event data and proxy symptoms of increased suicide risk from the Parkinson's Disease Questionnaire (PDQ-39) and the Short Form Health Survey (SF-36) were collected. In Phase 1, no suicide behaviours were reported, and new-onset suicide ideation was rare (1.9% for DBS vs 0.9% for BMT; Fisher's exact p=0.61). Proxy symptoms of relevance to suicide ideation were similar in the two groups. Rates of suicide ideation at 6 months were similar for patients randomised to STN versus GPi DBS (1.5% vs 0.7%; Fisher's exact p=0.61), but several proxy symptoms were worse in the STN group. Results from the randomised, controlled phase of a DBS surgery study in PD patients do not support a direct association between DBS surgery and an increased risk for suicide ideation and behaviours.

  5. Automatic trajectory planning of DBS neurosurgery from multi-modal MRI datasets.

    Science.gov (United States)

    Bériault, Silvain; Al Subaie, Fahd; Mok, Kelvin; Sadikot, Abbas F; Pike, G Bruce

    2011-01-01

    We propose an automated method for preoperative trajectory planning of deep brain stimulation image-guided neurosurgery. Our framework integrates multi-modal MRI analysis (T1w, SWI, TOF-MRA) to determine an optimal trajectory to DBS targets (subthalamic nuclei and globus pallidus interna) while avoiding critical brain structures for prevention of hemorrhages, loss of function and other complications. Results show that our method is well suited to aggregate many surgical constraints and allows the analysis of thousands of trajectories in less than 1/10th of the time for manual planning. Finally, a qualitative evaluation of computed trajectories resulted in the identification of potential new constraints, which are not addressed in the current literature, to better mimic the decision-making of the neurosurgeon during DBS planning.

  6. The effects of DBS patterns on basal ganglia activity and thalamic relay : a computational study.

    Science.gov (United States)

    Agarwal, Rahul; Sarma, Sridevi V

    2012-08-01

    Thalamic neurons receive inputs from cortex and their responses are modulated by the basal ganglia (BG). This modulation is necessary to properly relay cortical inputs back to cortex and downstream to the brain stem when movements are planned. In Parkinson's disease (PD), the BG input to thalamus becomes pathological and relay of motor-related cortical inputs is compromised, thereby impairing movements. However, high frequency (HF) deep brain stimulation (DBS) may be used to restore relay reliability, thereby restoring movements in PD patients. Although therapeutic, HF stimulation consumes significant power forcing surgical battery replacements, and may cause adverse side effects. Here, we used a biophysical-based model of the BG-Thalamus motor loop in both healthy and PD conditions to assess whether low frequency stimulation can suppress pathological activity in PD and enable the thalamus to reliably relay movement-related cortical inputs. We administered periodic pulse train DBS waveforms to the sub-thalamic nucleus (STN) with frequencies ranging from 0-140 Hz, and computed statistics that quantified pathological bursting, oscillations, and synchronization in the BG as well as thalamic relay of cortical inputs. We found that none of the frequencies suppressed all pathological activity in BG, though the HF waveforms recovered thalamic reliability. Our rigorous study, however, led us to a novel DBS strategy involving low frequency multi-input phase-shifted DBS, which successfully suppressed pathological symptoms in all BG nuclei and enabled reliable thalamic relay. The neural restoration remained robust to changes in the model parameters characterizing early to late PD stages.

  7. Intraoperative CT verification of electrode localization in DBS surgery in Parkinson's disease

    Directory of Open Access Journals (Sweden)

    P. Sokal

    2015-03-01

    Conclusions: Intraoperative CT is a helpful tool in DBS procedures and enables comparison of preoperative plans with the final trajectory and localization of the tip of electrode visualized in CT in appropriate target. It eliminates necessity of post-op verification outside the operating room. All changes can be done during the procedure. It also allows to rule out the intracerebral haematoma caused by implantation.

  8. Automated assessment of symptom severity changes during deep brain stimulation (DBS) therapy for Parkinson's disease.

    Science.gov (United States)

    Angeles, Paolo; Tai, Yen; Pavese, Nicola; Wilson, Samuel; Vaidyanathan, Ravi

    2017-07-01

    Deep brain stimulation (DBS) is currently being used as a treatment for symptoms of Parkinson's disease (PD). Tracking symptom severity progression and deciding the optimal stimulation parameters for people with PD is extremely difficult. This study presents a sensor system that can quantify the three cardinal motor symptoms of PD - rigidity, bradykinesia and tremor. The first phase of this study assesses whether data recorded from the system during physical examinations can be used to correlate to clinician's severity score using supervised machine learning (ML) models. The second phase concludes whether the sensor system can distinguish differences before and after DBS optimisation by a clinician when Unified Parkinson's Disease Rating Scale (UPDRS) scores did not change. An average accuracy of 90.9 % was achieved by the best ML models in the first phase, when correlating sensor data to clinician's scores. Adding on to this, in the second phase of the study, the sensor system was able to pick up discernible differences before and after DBS optimisation sessions in instances where UPDRS scores did not change.

  9. Apathy and Reduced Speed of Processing Underlie Decline in Verbal Fluency following DBS

    Directory of Open Access Journals (Sweden)

    Jennifer A. Foley

    2017-01-01

    Full Text Available Objective. Reduced verbal fluency is a strikingly uniform finding following deep brain stimulation (DBS for Parkinson’s disease (PD. The precise cognitive mechanism underlying this reduction remains unclear, but theories have suggested reduced motivation, linguistic skill, and/or executive function. It is of note, however, that previous reports have failed to consider the potential role of any changes in speed of processing. Thus, the aim of this study was to examine verbal fluency changes with a particular focus on the role of cognitive speed. Method. In this study, 28 patients with PD completed measures of verbal fluency, motivation, language, executive functioning, and speed of processing, before and after DBS. Results. As expected, there was a marked decline in verbal fluency but also in a timed test of executive functions and two measures of speed of processing. Verbal fluency decline was associated with markers of linguistic and executive functioning, but not after speed of processing was statistically controlled for. In contrast, greater decline in verbal fluency was associated with higher levels of apathy at baseline, which was not associated with changes in cognitive speed. Discussion. Reduced generativity and processing speed may account for the marked reduction in verbal fluency commonly observed following DBS.

  10. In vivo mapping of current density distribution in brain tissues during deep brain stimulation (DBS

    Directory of Open Access Journals (Sweden)

    Saurav Z. K. Sajib

    2017-01-01

    Full Text Available New methods for in vivo mapping of brain responses during deep brain stimulation (DBS are indispensable to secure clinical applications. Assessment of current density distribution, induced by internally injected currents, may provide an alternative method for understanding the therapeutic effects of electrical stimulation. The current flow and pathway are affected by internal conductivity, and can be imaged using magnetic resonance-based conductivity imaging methods. Magnetic resonance electrical impedance tomography (MREIT is an imaging method that can enable highly resolved mapping of electromagnetic tissue properties such as current density and conductivity of living tissues. In the current study, we experimentally imaged current density distribution of in vivo canine brains by applying MREIT to electrical stimulation. The current density maps of three canine brains were calculated from the measured magnetic flux density data. The absolute current density values of brain tissues, including gray matter, white matter, and cerebrospinal fluid were compared to assess the active regions during DBS. The resulting current density in different tissue types may provide useful information about current pathways and volume activation for adjusting surgical planning and understanding the therapeutic effects of DBS.

  11. In vivo mapping of current density distribution in brain tissues during deep brain stimulation (DBS)

    Science.gov (United States)

    Sajib, Saurav Z. K.; Oh, Tong In; Kim, Hyung Joong; Kwon, Oh In; Woo, Eung Je

    2017-01-01

    New methods for in vivo mapping of brain responses during deep brain stimulation (DBS) are indispensable to secure clinical applications. Assessment of current density distribution, induced by internally injected currents, may provide an alternative method for understanding the therapeutic effects of electrical stimulation. The current flow and pathway are affected by internal conductivity, and can be imaged using magnetic resonance-based conductivity imaging methods. Magnetic resonance electrical impedance tomography (MREIT) is an imaging method that can enable highly resolved mapping of electromagnetic tissue properties such as current density and conductivity of living tissues. In the current study, we experimentally imaged current density distribution of in vivo canine brains by applying MREIT to electrical stimulation. The current density maps of three canine brains were calculated from the measured magnetic flux density data. The absolute current density values of brain tissues, including gray matter, white matter, and cerebrospinal fluid were compared to assess the active regions during DBS. The resulting current density in different tissue types may provide useful information about current pathways and volume activation for adjusting surgical planning and understanding the therapeutic effects of DBS.

  12. A feature extraction method for adaptive DBS using an improved EMD.

    Science.gov (United States)

    Sun, Qifeng; Zhao, Dechun; Cheng, Shanshan; Hou, Xiaorong; Zhao, Xing; Tian, Yin

    2018-03-22

    Local field potential (LFP) of a patient with Parkinson's disease often shows abnormal oscillation phenomenon. Extracting and studying this phenomenon and designing adaptive deep brain stimulation (DBS) control library have great significance in the treatment of disease. This paper has designed a feature extraction method based on modified empirical mode decomposition (EMD) which extracts the abnormal oscillation signal in the time domain to increase the overall performance. The intrinsic mode function (IMF) component which contains abnormal oscillation is extracted by using EMD before an intrinsic characteristic of the oscillation signal is obtained. Abnormal oscillation signal is acquired using signal normalization, peak counting, and envelope method with a threshold which in turn keeps the integrity and accuracy as well as the efficiency. Comparative study of eight patients (six patients with DBS closed and drugs stopped; two patients with stimulation) has verified the feasibility of using modified EMD in extracting abnormal oscillation signal. The results showed that patients who take DBS suffer less abnormal oscillation than those who take no treatment. These results match the energy rise in the band of 3-30 Hz on local field potential spectrum of the patient with Parkinson's disease. Unlike previous oscillation extraction algorithm, improved EMD feature extraction method directly isolates abnormal oscillation signal from LFP. Significant improvement has been made in feature extraction algorithm in adaptability, real-time performance, and accuracy.

  13. Correction for the Hematocrit Bias in Dried Blood Spot Analysis Using a Nondestructive, Single-Wavelength Reflectance-Based Hematocrit Prediction Method.

    Science.gov (United States)

    Capiau, Sara; Wilk, Leah S; De Kesel, Pieter M M; Aalders, Maurice C G; Stove, Christophe P

    2018-02-06

    The hematocrit (Hct) effect is one of the most important hurdles currently preventing more widespread implementation of quantitative dried blood spot (DBS) analysis in a routine context. Indeed, the Hct may affect both the accuracy of DBS methods as well as the interpretation of DBS-based results. We previously developed a method to determine the Hct of a DBS based on its hemoglobin content using noncontact diffuse reflectance spectroscopy. Despite the ease with which the analysis can be performed (i.e., mere scanning of the DBS) and the good results that were obtained, the method did require a complicated algorithm to derive the total hemoglobin content from the DBS's reflectance spectrum. As the total hemoglobin was calculated as the sum of oxyhemoglobin, methemoglobin, and hemichrome, the three main hemoglobin derivatives formed in DBS upon aging, the reflectance spectrum needed to be unmixed to determine the quantity of each of these derivatives. We now simplified the method by only using the reflectance at a single wavelength, located at a quasi-isosbestic point in the reflectance curve. At this wavelength, assuming 1-to-1 stoichiometry of the aging reaction, the reflectance is insensitive to the hemoglobin degradation and only scales with the total amount of hemoglobin and, hence, the Hct. This simplified method was successfully validated. At each quality control level as well as at the limits of quantitation (i.e., 0.20 and 0.67) bias, intra- and interday imprecision were within 10%. Method reproducibility was excellent based on incurred sample reanalysis and surpassed the reproducibility of the original method. Furthermore, the influence of the volume spotted, the measurement location within the spot, as well as storage time and temperature were evaluated, showing no relevant impact of these parameters. Application to 233 patient samples revealed a good correlation between the Hct determined on whole blood and the predicted Hct determined on venous DBS. The

  14. Laser based spot weld characterization

    Science.gov (United States)

    Jonietz, Florian; Myrach, Philipp; Rethmeier, Michael; Suwala, Hubert; Ziegler, Mathias

    2016-02-01

    Spot welding is one of the most important joining technologies, especially in the automotive industry. Hitherto, the quality of spot welded joints is tested mainly by random destructive tests. A nondestructive testing technique offers the benefit of cost reduction of the testing procedure and optimization of the fabrication process, because every joint could be examined. This would lead to a reduced number of spot welded joints, as redundancies could be avoided. In the procedure described here, the spot welded joint between two zinc-coated steel sheets (HX340LAD+Z100MB or HC340LA+ZE 50/50) is heated optically on one side. Laser radiation and flash light are used as heat sources. The melted zone, the so called "weld nugget" provides the mechanical stability of the connection, but also constitutes a thermal bridge between the sheets. Due to the better thermal contact, the spot welded joint reveals a thermal behavior different from the surrounding material, where the heat transfer between the two sheets is much lower. The difference in the transient thermal behavior is measured with time resolved thermography. Hence, the size of the thermal contact between the two sheets is determined, which is directly correlated to the size of the weld nugget, indicating the quality of the spot weld. The method performs well in transmission with laser radiation and flash light. With laser radiation, it works even in reflection geometry, thus offering the possibility of testing with just one-sided accessibility. By using heating with collimated laser radiation, not only contact-free, but also remote testing is feasible. A further convenience compared to similar thermographic approaches is the applicability on bare steel sheets without any optical coating for emissivity correction. For this purpose, a proper way of emissivity correction was established.

  15. Generation and evaluation of an ultra-high-field atlas with applications in DBS planning

    Science.gov (United States)

    Wang, Brian T.; Poirier, Stefan; Guo, Ting; Parrent, Andrew G.; Peters, Terry M.; Khan, Ali R.

    2016-03-01

    Purpose Deep brain stimulation (DBS) is a common treatment for Parkinson's disease (PD) and involves the use of brain atlases or intrinsic landmarks to estimate the location of target deep brain structures, such as the subthalamic nucleus (STN) and the globus pallidus pars interna (GPi). However, these structures can be difficult to localize with conventional clinical magnetic resonance imaging (MRI), and thus targeting can be prone to error. Ultra-high-field imaging at 7T has the ability to clearly resolve these structures and thus atlases built with these data have the potential to improve targeting accuracy. Methods T1 and T2-weighted images of 12 healthy control subjects were acquired using a 7T MR scanner. These images were then used with groupwise registration to generate an unbiased average template with T1w and T2w contrast. Deep brain structures were manually labelled in each subject by two raters and rater reliability was assessed. We compared the use of this unbiased atlas with two other methods of atlas-based segmentation (single-template and multi-template) for subthalamic nucleus (STN) segmentation on 7T MRI data. We also applied this atlas to clinical DBS data acquired at 1.5T to evaluate its efficacy for DBS target localization as compared to using a standard atlas. Results The unbiased templates provide superb detail of subcortical structures. Through one-way ANOVA tests, the unbiased template is significantly (p brain nuclei and an increase in accuracy over single-template and lower field strength atlases.

  16. DBS Electrodes With Single Disconnected Contacts: Long-Term Observation and Implications for the Management.

    Science.gov (United States)

    Allert, Niels; Jusciute, Egle; Quindt, Regina; Lindlau, Alexandra; Nolden, Brit Meike; Daryaeitabar, Mohammadreza; Karbe, Hans

    2018-04-27

    To evaluate the long-term course of quadripolar DBS electrodes with disconnected single contacts that cannot be used for DBS. Quadripolar electrodes with open circuits of single contacts or monopolar impedances >6500 Ω were identified from a cohort of 2082 electrodes from 1044 patients with variable movement disorders. The long-term course was analyzed from follow-up data. Disconnected contacts were found in 58 electrodes (2.8%) from 49 patients (4.7%). The dysfunction was restricted to one contact in 51 electrodes (87.9%), two contacts in 5 electrodes (8.6%), three contacts in 2 electrodes (3.4%). Onset was related to surgery (implantation, impulse generator replacement, or other surgical revision) in 34 electrodes (58.6%), trauma in 2 electrodes, undetermined in 11 electrodes, and occurred spontaneously after previous normal measurements in 11 electrodes (19.0%). Repeated measurements at follow-ups of ≥3 months were available in 39 electrodes. In 16 electrodes (41.0%) abnormal impedances persisted constantly during observations up to 11½ years (47 ± 35 months, median 41 months). In 21 electrodes (53.8%) abnormal impedances remained restricted to the initial contact(s) but varied considerably between measurements during up to six years (39 ± 18 months, median 38 months). Only two electrodes (5.1%) with initially one disconnected contact developed a disconnection of a second contact. Disconnections of single contacts occur with increasing cumulative incidence during long-term DBS. Surgery is the main causative risk factor. In the majority of electrodes, the dysfunction remains restricted to the initial contact(s). © 2018 International Neuromodulation Society.

  17. Using MDEFT MRI Sequences to Target the GPi in DBS Surgery.

    Science.gov (United States)

    Nowacki, Andreas; Fiechter, Michael; Fichtner, Jens; Debove, Ines; Lachenmayer, Lenard; Schüpbach, Michael; Oertel, Markus Florian; Wiest, Roland; Pollo, Claudio

    2015-01-01

    Recent advances in different MRI sequences have enabled direct visualization and targeting of the Globus pallidus internus (GPi) for DBS surgery. Modified Driven Equilibrium Fourier Transform (MDEFT) MRI sequences provide high spatial resolution and an excellent contrast of the basal ganglia with low distortion. In this study, we investigate if MDEFT sequences yield accurate and reliable targeting of the GPi and compare direct targeting based on MDEFT sequences with atlas-based targeting. 13 consecutive patients considered for bilateral GPi-DBS for dystonia or PD were included in this study. Preoperative targeting of the GPi was performed visually based on MDEFT sequences as well as by using standard atlas coordinates. Postoperative CT imaging was performed to calculate the location of the implanted leads as well as the active electrode(s). The coordinates of both visual and atlas based targets were compared. The stereotactic coordinates of the lead and active electrode(s) were calculated and projected on the segmented GPi. On MDEFT sequences the GPi was well demarcated in most patients. Compared to atlas-based planning the mean target coordinates were located significantly more posterior. Subgroup analysis showed a significant difference in the lateral coordinate between dystonia (LAT = 19.33 ± 0.90) and PD patients (LAT = 20.67 ± 1.69). Projected on the segmented preoperative GPi the active contacts of the DBS electrode in both dystonia and PD patients were located in the inferior and posterior part of the structure corresponding to the motor part of the GPi. MDEFT MRI sequences provide high spatial resolution and an excellent contrast enabling precise identification and direct visual targeting of the GPi. Compared to atlas-based targeting, it resulted in a significantly different mean location of our target. Furthermore, we observed a significant variability of the target among the PD and dystonia subpopulation suggesting accurate targeting for each individual

  18. Experimental results supporting the determination of service quality objectives for DBS systems

    Science.gov (United States)

    Chouinard, G.; Whyte, W. A., Jr.; Goldberg, A. A.; Jones, B. L.

    1985-01-01

    A summary of the results of a joint United States and Canadian program on subjective measurements of the picture degradation caused by noise and interference on an NTSC encoded color television signal is given in this paper. The effects of system noise, cochannel and adjacent channel interference, and both single entry and aggregate as well as a combination of these types of interference were subjectively evaluated by expert and nonexpert viewers under reference conditions. These results were used to develop the rationale used at RARC '83 to establish the service quality objective for planning the DBS service for the American continents.

  19. Quantitative determination of atenolol in dried blood spot samples by LC-HRMS: a potential method for assessing medication adherence.

    Science.gov (United States)

    Lawson, Graham; Cocks, Elizabeth; Tanna, Sangeeta

    2012-05-15

    The use of blood spot collection cards was investigated as a means of obtaining small volume samples for the quantification of therapeutic drugs for assessing medication adherence. A liquid chromatography-high resolution TOF mass spectrometry (LC-HRMS) method, based on the measurement at the accurate mass to charge ratio of the target analyte, was used to ensure specificity for atenolol in the dried blood spot (DBS) samples. A working method was developed and validated. For the preparation of DBS samples whole blood spiked with analyte was used to produce 30 μl blood spots on specimen collection cards. A 5mm disc was cut from the dried blood spot and extracted using methanol:water (60:40, v/v) containing the internal standard, atenolol-d(7). Extracts were vortexed, sonicated and then centrifuged. Gradient chromatographic elution was achieved using an Ascentis Express C18 100mm×2.1mm column and a mobile phase flow rate of 0.2 ml/min and the column oven temperature at 30 °C. MS detection was carried out in electrospray positive ion mode for target ions at accurate mass m/z 267.1703 for atenolol and 274.2143 for the IS. Drug extraction efficiency from spiked blood spots was demonstrated to be 96±5% and the drug was stable in DBS for at least 10 weeks. The developed LC-HRMS method was linear within the tested calibration range of 25-1500 ng/ml and validation showed the accuracy (relative error) and precision (coefficient of variation) values were within the pre-defined limits of ≤ 5% at all concentrations with a limit of quantification of 25 ng/ml. Factors with potential to affect drug quantification measurements such as the matrix effects, volume of blood applied onto the collection card and effect of different sampling cards were investigated. The developed LC-HRMS method was applied to blood spots on sampling card taken from adult healthy volunteers previously administered a 50mg atenolol tablet and a DBS concentration-time profile was obtained for atenolol

  20. A comparative study between detached leaf and plastic growth pouches techniques on the infection of pseudocercospora leaf spot disease of cowpea cultivars (Vigna unguiculata L. Walp) in northeast Thailand.

    Science.gov (United States)

    Sinsiri, N; Laohasiriwong, S

    2009-03-01

    This glasshouse experiment was carried out in the 2004 at the Department of Agricultural Production, Faculty of Technology, Mahasarakham University, Mahasarakham 4400, Northeast Thailand to compare amounts of infection of Pseudocercospora leaf spot disease in leaves of cowpea cultivars being screened between detached leaf and plastic growth pouches techniques. The experiment was laid in a factorial arranged in a Randomized Complete Block Design (RCBD) with four replications. KVC7, IT81D-1228-14-1 and KKU25 cowpea cultivars were used as factor A, detached leaf and plastic growth pouches techniques were used as factor B and four levels of the concentrations of the spores of the disease, i.e., 0, l x 10(4), 5 x 10(4) and 1 x 10(5) of disease forming units mL(-1) of distilled water were used as factor C. The results showed that KVC7 and IT81D-1228-14-1 cultivars possessed immune and high resistant properties against the disease, respectively, whereas KKU25 cultivar ranked as a susceptible cultivar. Detached leaf technique gave higher amount of infection of the disease than plastic growth pouches technique and the differences were highly significant. A plentiful amount of Infected disease was attained with an inoculation rate of l x 10(5) forming units mL(-1) of distilled water, which was considered too high and the most appropriate concentrations for use lie on both concentrations, i.e., 1 x 10(4) and 5 x 10(4) forming units mL(-1) of distilled water. An interaction among factors AxBxC was severely found with KKU25 cultivar, particularly on day 28 after inoculation, whilst other two cultivars gave a minute amount of disease incidences (%) where detached leaf technique gave much higher disease incidences than plastic growth pouches technique, thus detached leaf technique should be of higher advantages.

  1. A proof-of-principle simulation for closed-loop control based on preexisting experimental thalamic DBS-enhanced instrumental learning.

    Science.gov (United States)

    Wang, Ching-Fu; Yang, Shih-Hung; Lin, Sheng-Huang; Chen, Po-Chuan; Lo, Yu-Chun; Pan, Han-Chi; Lai, Hsin-Yi; Liao, Lun-De; Lin, Hui-Ching; Chen, Hsu-Yan; Huang, Wei-Chen; Huang, Wun-Jhu; Chen, You-Yin

    Deep brain stimulation (DBS) has been applied as an effective therapy for treating Parkinson's disease or essential tremor. Several open-loop DBS control strategies have been developed for clinical experiments, but they are limited by short battery life and inefficient therapy. Therefore, many closed-loop DBS control systems have been designed to tackle these problems by automatically adjusting the stimulation parameters via feedback from neural signals, which has been reported to reduce the power consumption. However, when the association between the biomarkers of the model and stimulation is unclear, it is difficult to develop an optimal control scheme for other DBS applications, i.e., DBS-enhanced instrumental learning. Furthermore, few studies have investigated the effect of closed-loop DBS control for cognition function, such as instrumental skill learning, and have been implemented in simulation environments. In this paper, we proposed a proof-of-principle design for a closed-loop DBS system, cognitive-enhancing DBS (ceDBS), which enhanced skill learning based on in vivo experimental data. The ceDBS acquired local field potential (LFP) signal from the thalamic central lateral (CL) nuclei of animals through a neural signal processing system. A strong coupling of the theta oscillation (4-7 Hz) and the learning period was found in the water reward-related lever-pressing learning task. Therefore, the theta-band power ratio, which was the averaged theta band to averaged total band (1-55 Hz) power ratio, could be used as a physiological marker for enhancement of instrumental skill learning. The on-line extraction of the theta-band power ratio was implemented on a field-programmable gate array (FPGA). An autoregressive with exogenous inputs (ARX)-based predictor was designed to construct a CL-thalamic DBS model and forecast the future physiological marker according to the past physiological marker and applied DBS. The prediction could further assist the design of

  2. Spot market for uranium

    International Nuclear Information System (INIS)

    Colhoun, C.

    1982-01-01

    The spot market is always quoted for the price of uranium because little information is available about long-term contracts. A review of the development of spot market prices shows the same price curve swings that occur with all raw materials. Future long-term contracts will probably be lower to reflect spot market prices, which are currently in the real-value range of $30-$35. An upswing in the price of uranium could come in the next few months as utilities begin making purchases and trading from stockpiles. The US, unlike Europe and Japan, has already reached a supply and demand point where the spot market share is increasing. Forecasters cannot project the market price, they can only predict the presence of an oscillating spot or a secondary market. 5 figures

  3. Bioenergy for District Bioheating System (DBS) from eucalyptus residues in a European coal-producing region

    International Nuclear Information System (INIS)

    Paredes-Sánchez, José P.; López-Ochoa, Luis M.; López-González, Luis M.; Xiberta-Bernat, Jorge

    2016-01-01

    Highlights: • The paper introduces a combined method to evaluate bioenergy. • Forest biomass needs to be studied as a fuel supplier and carbon sink. • The forests under study produce about 28 kt dry and 0.15 Mt CO 2 per year. • Examined a District Bioheating System (DBS) with the available biomass. - Abstract: Since forest biomass can substitute for CO 2 -emitting fossil fuels in the energy sector, forest management can greatly affect the global carbon cycle. Eucalyptus globulus has adapted very well in the coal region of the Principality of Asturias (Northwestern Spain) and has become highly regarded as a valuable raw material for the pulp and paper industry. In the present work, the Eucalyptus globulus is studied as a key natural energy source in order to improve existing methods and develop new ways of optimizing the evaluation and use of both forest biomass and woody residue in energy systems, in accordance with sustainable forestry industry safety and environmental requirements. The feasibility of utilizing forest biomass instead of natural gas in a District Bioheating System (DBS) has been examined based on an analysis of its economical and environmental impacts.

  4. Penicillin Dried Blood Spot Assay for Use in Patients Receiving Intramuscular Benzathine Penicillin G and Other Penicillin Preparations To Prevent Rheumatic Fever.

    Science.gov (United States)

    Page-Sharp, Madhu; Coward, Jonathan; Moore, Brioni R; Salman, Sam; Marshall, Lewis; Davis, Timothy M E; Batty, Kevin T; Manning, Laurens

    2017-08-01

    Rheumatic heart disease (RHD) remains an important global health challenge. Administration of benzathine penicillin (BPG) every 3 to 4 weeks is recommended as a secondary prophylaxis to prevent recurrent episodes of acute rheumatic fever and subsequent RHD. Following intramuscular injection, BPG is hydrolyzed to penicillin G (benzylpenicillin). However, little is known of the pharmacokinetics (PK) of BPG in pediatric populations at high risk of RHD or of the pharmacokinetic-pharmacodynamic relationship between penicillin exposure and clinically relevant outcomes. Dried blood spot (DBS) assays can facilitate PK studies in situations where frequent venous blood sampling is logistically difficult. A liquid chromatography-mass spectroscopy assay for penicillin G in plasma and DBS was developed and validated. Application of the DBS assay for PK studies was confirmed using samples from adult patients receiving penicillin as part of an infection management plan. The limit of quantification for penicillin G in DBS was 0.005 mg/liter. Penicillin G is stable in DBS for approximately 12 h at room temperature (22°C), 6 days at 4°C, and >1 month at -20°C. Plasma and DBS penicillin G concentrations for patients receiving BPG and penicillin G given via bolus doses correlated well and had comparable time-concentration profiles. There was poor correlation for patients receiving penicillin via continuous infusions, perhaps as a result of the presence of residual penicillin in the peripherally inserted central catheter, from which the plasma samples were collected. The present DBS penicillin G assay can be used as a surrogate for plasma concentrations to provide valid PK data for studies of BPG and other penicillin preparations developed to prevent rheumatic fever and RHD. Copyright © 2017 American Society for Microbiology.

  5. Automated high-capacity on-line extraction and bioanalysis of dried blood spot samples using liquid chromatography/high-resolution accurate mass spectrometry.

    Science.gov (United States)

    Oliveira, Regina V; Henion, Jack; Wickremsinhe, Enaksha R

    2014-11-30

    Pharmacokinetic data to support clinical development of pharmaceuticals are routinely obtained from liquid plasma samples. The plasma samples require frozen shipment and storage and are extracted off-line from the liquid chromatography/tandem mass spectrometry (LC/MS/MS) systems. In contrast, the use of dried blood spot (DBS) sampling is an attractive alternative in part due to its benefits in microsampling as well as simpler sample storage and transport. However, from a practical aspect, sample extraction from DBS cards can be challenging as currently performed. The goal of this report was to integrate automated serial extraction of large numbers of DBS cards with on-line liquid chromatography/high-resolution accurate mass spectrometry (LC/HRAMS) bioanalysis. An automated system for direct DBS extraction coupled to a LC/HRAMS was employed for the quantification of midazolam (MDZ) and α-hydroxymidazolam (α-OHMDZ) in human blood. The target analytes were directly extracted from the DBS cards onto an on-line chromatographic guard column followed by HRAMS detection. No additional sample treatment was required. The automated DBS LC/HRAMS method was developed and validated, based on the measurement at the accurate mass-to-charge ratio of the target analytes to ensure specificity for the assay. The automated DBS LC/HRAMS method analyzed a DBS sample within 2 min without the need for punching or additional off-line sample treatment. The fully automated analytical method was shown to be sensitive and selective over the concentration range of 5 to 2000 ng/mL. Intra- and inter-day precision and accuracy was less than 15% (less than 20% at the LLOQ). The validated method was successfully applied to measure MDZ and α-OHMDZ in an incurred human sample after a single 7.5 mg dose of MDZ. The direct DBS LC/HRAMS method demonstrated successful implementation of automated DBS extraction and bioanalysis for MDZ and α-OHMDZ. This approach has the potential to promote workload

  6. Does suppression of oscillatory synchronisation mediate some of the therapeutic effects of DBS in patients with Parkinson's disease?

    Science.gov (United States)

    Eusebio, Alexandre; Cagnan, Hayriye; Brown, Peter

    2012-01-01

    There is growing evidence for exaggerated oscillatory neuronal synchronisation in patients with Parkinson's disease (PD). In particular, oscillations at around 20 Hz, in the so-called beta frequency band, relate to the cardinal symptoms of bradykinesia and rigidity. Deep brain stimulation (DBS) of the subthalamic nucleus (STN) can significantly improve these motor impairments. Recent evidence has demonstrated reduction of beta oscillations concurrent with alleviation of PD motor symptoms, raising the possibility that suppression of aberrant activity may mediate the effects of DBS. Here we review the evidence supporting suppression of pathological oscillations during stimulation and discuss how this might underlie the efficacy of DBS. We also consider how beta activity may provide a feedback signal suitable for next generation closed-loop and intelligent stimulators.

  7. Dried blood spots and parallel artificial liquid membrane extraction-A simple combination of microsampling and microextraction.

    Science.gov (United States)

    Ask, Kristine Skoglund; Øiestad, Elisabeth Leere; Pedersen-Bjergaard, Stig; Gjelstad, Astrid

    2018-06-07

    In this paper, parallel artificial liquid membrane extraction (PALME) was used for the first time to clean-up dried blood spots (DBS) prior to ultra-high performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS). Fundamental studies exploring amongst others desorption from the DBS in alkaline or acidic aqueous conditions, total extraction time and absolute recoveries were executed. Desorption and PALME were performed using a set of two 96-well plates, one of them housing the sample and the other comprising the supported liquid membrane (SLM) and the acceptor solution. In one procedure, amitriptyline and quetiapine (basic model analytes) were desorbed from the DBS using 250 μL of 10 mM sodium hydroxide solution (aqueous), and subsequently extracted through the SLM consisting of 4 μL of 1% trioctylamine in dodecyl acetate, and further into an acceptor solution consisting of 50 μL of 20 mM formic acid. In a second procedure, ketoprofen, fenoprofen, flurbiprofen, and ibuprofen (acidic model analytes) were desorbed from the DBS into 20 mM formic acid, extracted through an SLM with dihexyl ether, and further into an acceptor solution of 25 mM ammonia. Within 60 min of PALME, both basic and acidic model analytes were effectively desorbed from the DBS and extracted into the acceptor solution, which was injected directly into the analytical instrument. Recoveries between 63 and 85% for the six model analytes were obtained. PALME provided excellent clean-up from the DBS samples, and acceptor solutions were free from phospholipids. Linearity was obtained with r 2  > 0.99 for five of the six analytes. Accuracy, precision and UHPLC-MS/MS matrix effects were in accordance with the European Medicines Agency (EMA) guideline. Based on these experiments, PALME shows great potential for future processing of DBS in a short and simple way, and with the presented setup, up to 96 DBS can be processed within a total extraction time of 60

  8. Mononucleosis spot test

    Science.gov (United States)

    Monospot test; Heterophile antibody test; Heterophile agglutination test; Paul-Bunnell test; Forssman antibody test ... The mononucleosis spot test is done when symptoms of mononucleosis are ... Fatigue Fever Large spleen (possibly) Sore throat Tender ...

  9. A simple method to quantitate IP-10 in dried blood and plasma spots.

    Directory of Open Access Journals (Sweden)

    Martine G Aabye

    Full Text Available BACKGROUND: Antigen specific release of IP-10 is an established marker for infection with M.tuberculosis. Compared to IFN-γ, IP-10 is released in 100-fold higher concentrations enabling the development of novel assays for detection. Dried blood spots are a convenient sample for high throughput newborn screening. AIM: To develop a robust and sensitive ELISA-based assay for IP-10 detection in plasma, dried blood spots (DBS and dried plasma spots (DPS; to validate the ELISA in clinically relevant samples; and to assess the performance of the assay for detection of Cytomegalovirus (CMV and M.tuberculosis specific immune responses. METHOD: We raised mice and rat monoclonal antibodies against human IP-10 and developed an ELISA. The assay was validated and applied to the detection of CMV and M.tuberculosis specific responses in 18 patients with immune reactivity towards M.tuberculosis and 32 healthy controls of which 22 had immune reactivity towards CMV and none towards M.tuberculosis. We compared the performance of this new assay to IFN-γ. RESULTS: The ELISA was reliable for IP-10 detection in both plasma and filter paper samples. The linear range of the ELISA was 2.5-600 pg/ml. IFN-γ was not readily detectable in DPS samples. IP-10 was stabile in filter paper samples for at least 4 weeks at 37 °C. The correlation between IP-10 detected in plasma, DPS and DBS samples was excellent (r(2>0.97. CONCLUSIONS: This newly developed assay is reliable for IP-10 quantification in plasma, DBS and DPS samples from antigen stimulated and non-stimulated whole blood. The filter paper assays enable easy sample acquisition and transport at ambient temperature e.g. via the postal system. The system can potentially simplify diagnostic assays for M.tuberculosis and CMV infection.

  10. A critical reflection on the technological development of deep brain stimulation (DBS

    Directory of Open Access Journals (Sweden)

    Christian eIneichen

    2014-09-01

    Full Text Available Since the translational research findings of Benabid and colleagues, which partly led to their seminal paper regarding the treatment of mainly tremor-dominant Parkinson patients through thalamic high-frequency-stimulation (HFS in 1987, we still struggle with identifying a satisfactory mechanistic explanation of the underlying principles of Deep Brain Stimulation. Furthermore, the technological advance of DBS devices (electrodes and implantable pulse generators, IPG's has shown a distinct lack of dynamic progression. In light of this we argue that it is time to leave the paleolithic age and enter hellenistic times: the device-manufacturing industry and the medical community together should put more emphasis on advancing the technology rather than resting on their laurels.

  11. Superluminal Spot Pair Events in Astronomical Settings: Sweeping Beams

    Science.gov (United States)

    Nemiroff, Robert J.

    2015-02-01

    Sweeping beams of light can cast spots moving with superluminal speeds across scattering surfaces. Such faster-than-light speeds are well-known phenomena that do not violate special relativity. It is shown here that under certain circumstances, superluminal spot pair creation and annihilation events can occur that provide unique information to observers. These spot pair events are not particle pair events-they are the sudden creation or annihilation of a pair of relatively illuminated spots on a scattering surface. Real spot pair illumination events occur unambiguously on the scattering surface when spot speeds diverge, while virtual spot pair events are observer dependent and perceived only when real spot radial speeds cross the speed of light. Specifically, a virtual spot pair creation event will be observed when a real spot's speed toward the observer drops below c, while a virtual spot pair annihilation event will be observed when a real spot's radial speed away from the observer rises above c. Superluminal spot pair events might be found angularly, photometrically, or polarimetrically, and might carry useful geometry or distance information. Two example scenarios are briefly considered. The first is a beam swept across a scattering spherical object, exemplified by spots of light moving across Earth's Moon and pulsar companions. The second is a beam swept across a scattering planar wall or linear filament, exemplified by spots of light moving across variable nebulae including Hubble's Variable Nebula. In local cases where the sweeping beam can be controlled and repeated, a three-dimensional map of a target object can be constructed. Used tomographically, this imaging technique is fundamentally different from lens photography, radar, and conventional lidar.

  12. Hyperspectral imaging and multivariate analysis in the dried blood spots investigations

    Science.gov (United States)

    Majda, Alicja; Wietecha-Posłuszny, Renata; Mendys, Agata; Wójtowicz, Anna; Łydżba-Kopczyńska, Barbara

    2018-04-01

    The aim of this study was to apply a new methodology using the combination of the hyperspectral imaging and the dry blood spot (DBS) collecting. Application of the hyperspectral imaging is fast and non-destructive. DBS method offers the advantage also on the micro-invasive blood collecting and low volume of required sample. During experimental step, the reflected light was recorded by two hyperspectral systems. The collection of 776 spectral bands in the VIS-NIR range (400-1000 nm) and 256 spectral bands in the SWIR range (970-2500 nm) was applied. Pixel has the size of 8 × 8 and 30 × 30 µm for VIS-NIR and SWIR camera, respectively. The obtained data in the form of hyperspectral cubes were treated with chemometric methods, i.e., minimum noise fraction and principal component analysis. It has been shown that the application of these methods on this type of data, by analyzing the scatter plots, allows a rapid analysis of the homogeneity of DBS, and the selection of representative areas for further analysis. It also gives the possibility of tracking the dynamics of changes occurring in biological traces applied on the surface. For the analyzed 28 blood samples, described method allowed to distinguish those blood stains because of time of apply.

  13. Effects of DBS, premotor rTMS, and levodopa on motor function and silent period in advanced Parkinson's disease

    DEFF Research Database (Denmark)

    Bäumer, Tobias; Hidding, Ute; Hamel, Wolfgang

    2009-01-01

    Deep brain stimulation (DBS) of the subthalamic nucleus (STN) is a widely used and highly effective treatment for patients with advanced Parkinson's disease (PD). Repetitive TMS (rTMS) applied to motor cortical areas has also been shown to improve symptoms in PD and modulate motor cortical excita...

  14. 47 CFR 73.756 - System specifications for double-sideband (DBS) modulated emissions in the HF broadcasting service.

    Science.gov (United States)

    2010-10-01

    ... 47 Telecommunication 4 2010-10-01 2010-10-01 false System specifications for double-sideband (DBS) modulated emissions in the HF broadcasting service. 73.756 Section 73.756 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) BROADCAST RADIO SERVICES RADIO BROADCAST SERVICES International Broadcast...

  15. Positive outcomes and causal insufficiency do not rule out the risk (and importance) of DBS-related identity changes

    NARCIS (Netherlands)

    Mecacci, G.; Haselager, W.F.G.

    2017-01-01

    Gilbert and colleagues (2017) conducted an important qualitative study aimed at exploring the phenomenal field of experiences in deep brain stimulation (DBS) implanted patients. In particular, the study delves into the concept of self-estrangement and the qualitative experiences that are connected

  16. Evaluation of functional goal outcomes using the Canadian Occupational Performance Measure (COPM) following Deep Brain Stimulation (DBS) in childhood dystonia.

    Science.gov (United States)

    Gimeno, Hortensia; Tustin, Kylee; Lumsden, Daniel; Ashkan, Keyoumars; Selway, Richard; Lin, Jean-Pierre

    2014-05-01

    To evaluate the functional goal-directed outcomes of Deep Brain Stimulation (DBS) in childhood dystonia according to aetiology and to explore relationship with a traditional impairment-based measure. This is a prospective case series study involving thirty children with dystonia with a 1-year follow-up post-DBS. The Canadian Occupational Performance Measure (COPM) and Burke-Fahn-Marsden Dystonia Rating Scale (BFMDRS) were used as primary outcome measures. Results were analysed based on aetiology in 3 groups: 1. primary/primary plus dystonia; 2. secondary dystonia-cerebral palsy (CP); 3. secondary dystonia-non-CP group. Correlation between functional outcome using COPM and dystonia improvement as captured by BFMDRS was measured. All groups demonstrated significant improvement in individualised goal attainment, measured with the COPM, at 1-year post-DBS. The secondary dystonia-CP group also achieved significant improvement at 6 months for performance and satisfaction scores. In the majority of secondary dystonias, the BFMDRS failed to demonstrate significant improvement. A linear correlation between change in BFMDRS and COPM scores was observed when the entire cohort was analysed. DBS improved functional performance, independently of the dystonic phenotype. Improvements in individualized COPM functional goal areas were seen in the absence of significant changes in BFMDRS scores, highlighting the relative insensitivity of impairment scales in this patient group. Copyright © 2014 European Paediatric Neurology Society. Published by Elsevier Ltd. All rights reserved.

  17. Acute and Chronic Mood and Apathy Outcomes from a randomized study of unilateral STN and GPi DBS.

    Directory of Open Access Journals (Sweden)

    Michael S Okun

    Full Text Available To study mood and behavioral effects of unilateral and staged bilateral subthalamic nucleus (STN and globus pallidus internus (GPi deep brain stimulation (DBS for Parkinson's disease (PD.There are numerous reports of mood changes following DBS, however, most have focused on bilateral simultaneous STN implants with rapid and aggressive post-operative medication reduction.A standardized evaluation was applied to a subset of patients undergoing STN and GPi DBS and who were also enrolled in the NIH COMPARE study. The Unified Parkinson Disease Rating Scale (UPDRS III, the Hamilton depression (HAM-D and anxiety rating scales (HAM-A, the Yale-Brown obsessive-compulsive rating scale (YBOCS, the Apathy Scale (AS, and the Young mania rating scale (YMRS were used. The scales were repeated at acute and chronic intervals. A post-operative strategy of non-aggressive medication reduction was employed.Thirty patients were randomized and underwent unilateral DBS (16 STN, 14 GPi. There were no baseline differences. The GPi group had a higher mean dopaminergic dosage at 1-year, however the between group difference in changes from baseline to 1-year was not significant. There were no differences between groups in mood and motor outcomes. When combining STN and GPi groups, the HAM-A scores worsened at 2-months, 4-months, 6-months and 1-year when compared with baseline; the HAM-D and YMRS scores worsened at 4-months, 6-months and 1-year; and the UPDRS Motor scores improved at 4-months and 1-year. Psychiatric diagnoses (DSM-IV did not change. No between group differences were observed in the cohort of bilateral cases.There were few changes in mood and behavior with STN or GPi DBS. The approach of staging STN or GPi DBS without aggressive medication reduction could be a viable option for managing PD surgical candidates. A study of bilateral DBS and of medication reduction will be required to better understand risks and benefits of a bilateral approach.

  18. Real-time polymerase chain reaction optimised for hepatitis C virus detection in dried blood spots from HIV-exposed infants, KwaZulu-Natal, South Africa

    OpenAIRE

    Anneta Naidoo; Raveen Parboosing; Pravi Moodley

    2016-01-01

    Background: There is a paucity of data on the prevalence of hepatitis C virus (HCV) in children, particularly in sub-Saharan Africa. A major obstacle in resource-limited settings for polymerase chain reaction (PCR) testing is the necessity for specimen transportation and storage at low temperatures. There are numerous recent studies of using real-time HCV PCR for diagnosis and screening of plasma and serum, but few have looked at using dried blood spot (DBS) specimens. Objectives: The aim ...

  19. Cotton-wool spots.

    Science.gov (United States)

    Brown, G C; Brown, M M; Hiller, T; Fischer, D; Benson, W E; Magargal, L E

    1985-01-01

    A series of 24 consecutive patients presenting with a fundus picture characterized by a predominance of cotton-wool spots, or a single cotton-wool spot, is reported. Excluded were patients with known diabetes mellitus. Etiologic conditions found included previously undiagnosed diabetes mellitus in five patients, systemic hypertension in five patients, cardiac valvular disease in two patients, radiation retinopathy in two patients, and severe carotid artery obstruction in two patients. Dermatomyositis, systemic lupus erythematosus, polyarteritis nodosa, leukemia, AIDS, Purtscher's retinopathy, metastatic carcinoma, intravenous drug abuse, partial central retinal artery obstruction, and giant cell arteritis were each found in one patient. In only one patient did a systemic workup fail to reveal an underlying cause. The presence of even one cotton-wool spot in an otherwise normal fundus necessitates an investigation to ascertain systemic etiologic factors.

  20. Simultaneous Testing for 6 Lysosomal Storage Disorders and X-Adrenoleukodystrophy in Dried Blood Spots by Tandem Mass Spectrometry.

    Science.gov (United States)

    Tortorelli, Silvia; Turgeon, Coleman T; Gavrilov, Dimitar K; Oglesbee, Devin; Raymond, Kimiyo M; Rinaldo, Piero; Matern, Dietrich

    2016-09-01

    Newborn screening for lysosomal storage disorders (LSD) has revealed that late-onset variants of these conditions are unexpectedly frequent and therefore may evade diagnosis. We developed an efficient and cost-effective multiplex assay to diagnose six LSDs and several peroxisomal disorders in patients presenting with diverse phenotypes at any age. Three 3-mm dried blood spot (DBS) punches were placed into individual microtiter plates. One disc was treated with a cocktail containing acid sphingomyelinase-specific substrate and internal standard (IS). To the second DBS we added a cocktail containing substrate and IS for β-glucosidase, acid α-glucosidase, α-galactosidase A, galactocerebrosidase, and α-L-iduronidase. The third DBS was extracted with methanol containing d4-C26 lysophosphatidylcholine as IS and stored until the enzyme plates were combined and purified by liquid-liquid and solid-phase extraction. The extracts were evaporated, reconstituted with the extract from the lysophosphatidylcholine plate, and analyzed by flow injection tandem mass spectrometry. Reference intervals were determined by analysis of 550 samples from healthy controls. DBS from confirmed patients with 1 of the 6 LSDs (n = 33), X-adrenoleukodystrophy (n = 9), or a peroxisomal biogenesis disorder (n = 5), as well as carriers for Fabry disease (n = 17) and X-adrenoleukodystrophy (n = 5), were analyzed for assay validation. Prospective clinical testing of 578 samples revealed 25 patients affected with 1 of the detectable conditions. Our flow injection tandem mass spectrometry approach is amenable to high-throughput population screening for Hurler disease, Gaucher disease, Niemann-Pick A/B disease, Pompe disease, Krabbe disease, Fabry disease, X-adrenoleukodystrophy, and peroxisomal biogenesis disorder in DBS. © 2016 American Association for Clinical Chemistry.

  1. Direct analysis of site-specific N-glycopeptides of serological proteins in dried blood spot samples.

    Science.gov (United States)

    Choi, Na Young; Hwang, Heeyoun; Ji, Eun Sun; Park, Gun Wook; Lee, Ju Yeon; Lee, Hyun Kyoung; Kim, Jin Young; Yoo, Jong Shin

    2017-08-01

    Dried blood spot (DBS) samples have a number of advantages, especially with respect to ease of collection, transportation, and storage and to reduce biohazard risk. N-glycosylation is a major post-translational modification of proteins in human blood that is related to a variety of biological functions, including metastasis, cell-cell interactions, inflammation, and immunization. Here, we directly analyzed tryptic N-glycopeptides from glycoproteins in DBS samples using liquid chromatography-tandem mass spectrometry (LC-MS/MS) without centrifugation of blood samples, depletion of major proteins, desalting of tryptic peptides, and enrichment of N-glycopeptides. Using this simple method, we identified a total of 41 site-specific N-glycopeptides from 16 glycoproteins in the DBS samples, from immunoglobulin gamma 1 (IgG-1, 10 mg/mL) down to complement component C7 (50 μg/mL). Of these, 32 N-glycopeptides from 14 glycoproteins were consistently quantified over 180 days stored at room temperature. The major abundant glycoproteins in the DBS samples were IgG-1 and IgG-2, which contain nine asialo-fucosylated complex types of 16 different N-glycopeptide isoforms. Sialo-non-fucosylated complex types were primarily detected in the other glycoproteins such as alpha-1-acid glycoprotein 1, 2, alpha-1-antitypsin, alpha-2-macroglobulin, haptoglobin, hemopexin, Ig alpha 1, 2 chain C region, kininogen-1, prothrombin, and serotransferrin. We first report the characterization of site-specific N-glycoproteins in DBS samples by LC-MS/MS with minimal sample preparation.

  2. Measurement and Comparison of Organic Compound Concentrations in Plasma, Whole Blood and Dried Blood Spot Samples

    Directory of Open Access Journals (Sweden)

    Stuart A Batterman

    2016-04-01

    Full Text Available The preferred sampling medium for measuring human exposures of persistent organic compounds (POPs is blood, and relevant sample types include whole blood, plasma, and dried blood spots (DBS. Because information regarding the performance and comparability of measurements across these sample types is limited, it is difficult to compare across studies. This study evaluates the performance of POP measurements in plasma, whole blood and DBS, and presents the distribution coefficients needed to convert concentrations among the three sample types. Blood samples were collected from adult volunteers, along with demographic and smoking information, and analyzed by GC/MS for organochlorine pesticides (OCPs, chlorinated hydrocarbons (CHCs, polychlorinated biphenyls (PCBs, and brominated diphenyl ethers (PBDEs. Regression models were used to evaluate the relationships between the sample types and possible effects of personal covariates. Distribution coefficients also were calculated using physically-based models.Across all compounds, concentrations in plasma were consistently the highest; concentrations in whole blood and DBS samples were comparable. Distribution coefficients for plasma to whole blood concentrations ranged from 1.74 to 2.26 for pesticides/CHCs, averaged 1.69 ± 0.06 for the PCBs, and averaged 1.65 ± 0.03 for the PBDEs. Regression models closely fit most chemicals (R2 > 0.80, and whole blood and DBS samples generally showed very good agreement. Distribution coefficients estimated using biologically-based models were near one and did not explain the observed distribution. Among the study population, median concentrations of several pesticides/CHCs and PBDEs exceeded levels reported in the 2007-2008 National Health and Nutrition Examination Survey, while levels of other OCPs and PBDEs were comparable or lower. Race and smoking status appeared to slightly affect plasma/blood concentration ratios for several POPs. The experimentally

  3. r-CBF brain SPET before surgery and during subthalamic nuclei (STN) high frequency stimulation (DBS) in Parkinson's Disease

    International Nuclear Information System (INIS)

    Gerundini, P.; Benti, R.; De Notaris, A.; Ferrari, M.; Raimondi, A.; Mariani, C.; Antonini, A.; Pezzoli, G.; Gaini, S.M.

    2002-01-01

    Deep brain stimulation (DBS) of the subthalamic nuclei (STN) can improve motor symptoms and reduces the need for medical therapy in severe Parkinson's Disease (PD). Moreover, DBS can affect, as the medical treatment, cerebral perfusion/metabolism even in cortical/subcortical areas not primarily involved in PD motor symptoms. Aim of the study was the assessment of r-CBF changes by mean of brain SPECT in severe PD .before surgery and during DBS of the STN. Methods. 14 PD patients (duration 15.2±5.1 ys; H and Y off-score 3.6±0.7) underwent STN electrode implantation. Residual motor dysfunction was assessed by UPDRS score up to one year after surgery. SPECT was performed after i.v. injection of Tc-99m ECD (740 MBq) in PD group before and 6-9 months after surgery and in 13 age matched normals. Standardized ROIs templates were applied in brain sections to generate perfusion ratios in the cerebral cortex and basal ganglia. Statistical Parametric Mapping (SPM) analysis of SPET studies was also obtained. Results: 6 months after surgery the mean UPDRS score improvement was 48.8±26.1% (DBS on) vs pre surgery. 8 patients (R+) had UPDRS improvement >50% (mean 67.7±8.8%); 6 patients (R-) had score improvement <50% (mean 22.9±18.9%). Before surgery, motor dysfunction during therapy was similar in R+ and R- groups (mean UPDRS 19.8±8.2 vs. 21.3±9.6). During BDS, UPDRS mean score without medical therapy was lower in R+ (15.6±5.6) vs. R- (35.0±12.4; p<0.001). ROIs and SPM analysis of pre-surgery SPET studies showed significant hypoperfusion (p<0.01) in the occipital gyri of PD vs control groups. No significant differences were found by comparing pre/post surgery SPECT patterns in whole PD group. However, in R- group SPECT showed significant hypoperfusion in pre-frontal areas, parietal and occipital gyri vs R+ patients (p<0.02) and controls (p<0.01). Before surgery, R+ group had borderline occipital hypoperfusion (p=0.04) and mild increase of putaminal perfusion (p=0.03) vs

  4. Medical students’ attitudes and perspectives regarding novel computer-based practical spot tests compared to traditional practical spot tests

    Science.gov (United States)

    Wijerathne, Buddhika; Rathnayake, Geetha

    2013-01-01

    Background Most universities currently practice traditional practical spot tests to evaluate students. However, traditional methods have several disadvantages. Computer-based examination techniques are becoming more popular among medical educators worldwide. Therefore incorporating the computer interface in practical spot testing is a novel concept that may minimize the shortcomings of traditional methods. Assessing students’ attitudes and perspectives is vital in understanding how students perceive the novel method. Methods One hundred and sixty medical students were randomly allocated to either a computer-based spot test (n=80) or a traditional spot test (n=80). The students rated their attitudes and perspectives regarding the spot test method soon after the test. The results were described comparatively. Results Students had higher positive attitudes towards the computer-based practical spot test compared to the traditional spot test. Their recommendations to introduce the novel practical spot test method for future exams and to other universities were statistically significantly higher. Conclusions The computer-based practical spot test is viewed as more acceptable to students than the traditional spot test. PMID:26451213

  5. Simultaneous determination of pentoxifylline, metabolites M1 (lisofylline), M4 and M5, and caffeine in plasma and dried blood spots for pharmacokinetic studies in preterm infants and neonates.

    Science.gov (United States)

    Page-Sharp, Madhu; Strunk, Tobias; Salman, Sam; Hibbert, Julie; Patole, Sanjay K; Manning, Laurens; Batty, Kevin T

    2017-11-30

    Advances in bioanalytical methods are facilitating micro-volume and dried blood spot (DBS) analysis of drugs in biological matrices for pharmacokinetic studies in children and neonates. We sought to develop a UPLC-MS/MS assay for simultaneous measurement of caffeine, pentoxifylline (PTX) and three metabolites of PTX in both plasma and DBS. Caffeine, PTX, the metabolites M1 (lisofylline), M4 and M5, and the internal standards (caffeine-d 9 and PTX-d 6 ) were separated using a Waters Aquity T3 UPLC C 18 column and gradient mobile phase (water-methanol-formic acid). Retention times for caffeine, M5, M4, PTX and M1 were 1.6, 1.7, 1.9, 2.0 and 2.1min, respectively, with a run time of 5min. The precision (≤10%) and accuracy (≤15%) across the concentration range 0.1-50mg/L for caffeine, PTX and the three metabolites in plasma and DBS were within accepted limits, as were the limits of quantification (100μg/L for caffeine and 10μg/L for PTX, M1, M4 and M5). Caffeine, PTX and the metabolites were stable in DBS for >34days at room and refrigerated temperatures. Plasma and DBS samples were obtained from 24 preterm infants recruited into a clinical pharmacokinetic study of PTX. Paired analysis indicated that DBS concentrations were 9% lower than concurrent plasma concentrations for caffeine, 7% lower for PTX (consistent with the blood:plasma ratio) and 13% lower for M1 (lisofylline). The validated UPLC-MS/MS method is suitable for micro-volume plasma and DBS analysis of caffeine, PTX and its metabolites for pharmacokinetic studies in paediatric patients. Copyright © 2017 Elsevier B.V. All rights reserved.

  6. Application des spots de sang séché en pharmacologie et en toxicologie

    OpenAIRE

    Deglon, Julien

    2012-01-01

    Dans le domaine de l’analyse biomédicale, le sang est de loin la matrice la plus couramment utilisée. Son obtention s’effectue traditionnellement par une ponction veineuse au niveau du bras. Un mode de prélèvement alternatif a fait son apparition dans les années 60 : les spots de sang séché sur papier filtre ou dried blood spots (DBS). Bien que les avantages (simplicité, micro volumes, transport, stockage et sécurité) aient été clairement identifiés, ce mode de prélèvements est longtemps rest...

  7. ESA uncovers Geminga's `hot spot'

    Science.gov (United States)

    2004-07-01

    regions of the star, they found that the ‘colour’ of the X-rays, which corresponds to their energy, changed as Geminga rotated. In particular, they could clearly see a distinct colour change when the hot spot came into view and then disappeared behind the star. This research closes the gap between the X-ray and gamma-ray emission from neutron stars. XMM-Newton has shown that they both can originate through the same physical mechanism, namely the acceleration of charged particles in the magnetosphere of these degenerate stars. "XMM-Newton’s Geminga observation has been particularly fruitful," said Norbert Schartel, ESA’s Project Scientist for XMM-Newton. "Last year, it yielded the discovery of the source tails and now it has found its rotating hot spot." Caraveo is already applying this new technique to other pulsating neutron stars observed by XMM-Newton looking for hot spots. This research represents an important new tool for understanding the physics of neutron stars. Notes for editors The original paper appeared on 16 July 2004, in Science magazine, under the title 'Phase-resolved spectroscopy of Geminga shows rotating hotspot(s)'. Besides P. Caraveo, the author list includes A. De Luca, S. Mereghetti, A. Pellizzoni and G. Bignami. During the search to track down this elusive celestial object, a co-author on the paper, Giovanni Bignami, named it Geminga almost 30 years ago. He was Principal Investigator of XMM-Newton's EPIC camera from 1987 to 1997 and is now Director of the Centre d'Etude Spatiale des Rayonnements (CESR, Toulouse). Geminga was first glimpsed as a mysterious source of gamma rays, coming from somewhere in the constellation Gemini by NASA's SAS-2 spacecraft in 1973. While searching to pin down its exact location and nature, Bignami named it Geminga because it was a ‘Gemini gamma-ray source’. As an astronomer in Milan, Italy, he was also aware that in his native dialect ‘gh'èminga’ means ‘it is not there’, which he found amusing. It

  8. Does suppression of oscillatory synchronisation mediate some of the therapeutic effects of DBS in patients with Parkinson’s disease?

    Directory of Open Access Journals (Sweden)

    Alexandre eEusebio

    2012-07-01

    Full Text Available There is growing evidence for exaggerated oscillatory neuronal synchronisation in patients with Parkinson’s disease. In particular, oscillations at around 20 Hz, in the so-called beta frequency band, relate to the cardinal symptoms of bradykinesia and rigidity. Deep brain stimulation of the subthalamic nucleus can significantly improve these motor impairments. Recent evidence has demonstrated reduction of beta oscillations concurrent with alleviation of PD motor symptoms, raising the possibility that suppression of aberrant activity may mediate the effects of DBS. Here we review the evidence supporting suppression of pathological oscillations during stimulation and discuss how this might underlie the efficacy of DBS. We also consider how beta activity may provide a feedback signal suitable for next generation closed loop and intelligent stimulators.

  9. Links to Other DBs (based on UniChem) - NBDC NikkajiRDF | LSDB Archive [Life Science Database Archive metadata

    Lifescience Database Archive (English)

    Full Text Available h URL - Data acquisition method The data was created from the mapping data between Nikkaji substances, and c...List Contact us NBDC NikkajiRDF Links to Other DBs (based on UniChem) Data detail Data name Links to Other D...s and chemical substances registered in other databases* by using skos:closeMatch. This is based on a work a..., Aggregated Computational Toxicology Resource (ACToR), BindingDB, and KNApSAcK. Data file File name: NBDC_NikkajiRDF_link2Othe...p/archive/nikkaji/LATEST/NBDC_NikkajiRDF_link2OtherDBs_basedOnUniChem.tar.gz File size: 48.3 MB Simple searc

  10. Ultrasonic assessment of tension shear strength in resistance spot welding

    Science.gov (United States)

    Moghanizadeh, Abbas

    2015-05-01

    Resistance spot welding is extensively used to join sheet steel in the automotive industry. Ultrasonic non-destructive techniques for evaluation of the mechanical properties of resistance spot welding are presented. The aim of this study is to develop the capability of the ultrasonic techniques as an efficient tool in the assessment of the welding characterization. Previous researches have indicated that the measurements of ultrasonic attenuation are sensitive to grain- size variations in an extensive range of metallic alloys. Other researchers have frequently described grain sizes which are able to have significant effects on the physical characteristics of the material. This research provides a novel method to estimate the tension-shear strengths of the resistance spot welding directly from the ultrasonic attenuation measurements. The effects of spot welding parameters on the ultrasonic waves are further investigated. The results confirm that it is possible to determine the spot welding parameters for individual quality by using ultrasonic test.

  11. The case for testing memory with both stories and word lists prior to dbs surgery for Parkinson's Disease.

    Science.gov (United States)

    Zahodne, Laura B; Bowers, Dawn; Price, Catherine C; Bauer, Russell M; Nisenzon, Anne; Foote, Kelly D; Okun, Michael S

    2011-04-01

    Patients seeking deep brain stimulation (DBS) surgery for Parkinson's disease (PD) typically undergo neuropsychological assessment to determine candidacy for surgery, with poor memory performance interpreted as a contraindication. Patients with PD may exhibit worse memory for word lists than for stories due to the lack of inherent organization in a list of unrelated words. Unfortunately, word list and story tasks are typically developed from different normative datasets, and the existence of a memory performance discrepancy in PD has been challenged. We compared recall of stories and word lists in 35 non-demented PD candidates for DBS. We administered commonly used neuropsychological measures of word list and story memory (Hopkins Verbal Learning Test, Logical Memory), along with a second word list task that was co-normed with the story task. Age-corrected scores were higher for the story task than for both word list tasks. Compared to story recall, word list recall correlated more consistently with motor severity and composite measures of processing speed, working memory, and executive functioning. These results support the classic view of fronto-subcortical contributions to memory in PD and suggest that executive deficits may influence word list recall more than story recall. We recommend a multi-componential memory battery in the neuropsychological assessment of DBS candidates to characterize both mesial temporal and frontal-executive memory processes. One should not rely solely on a word list task because patients exhibiting poor memory for word lists may perform better with stories and therefore deserve an interdisciplinary discussion for DBS surgery.

  12. Autonomy in Depressive Patients Undergoing DBS-Treatment: Informed Consent, Freedom of Will and DBS’ Potential to Restore It

    Directory of Open Access Journals (Sweden)

    Timo Beeker

    2017-06-01

    Full Text Available According to the World Health Organization, depression is one of the most common and most disabling psychiatric disorders, affecting at any given time approximately 325 million people worldwide. As there is strong evidence that depressive disorders are associated with a dynamic dysregulation of neural circuits involved in emotional processing, recently several attempts have been made to intervene directly in these circuits via deep brain stimulation (DBS in patients with treatment-resistant major depressive disorder (MDD. Given the promising results of most of these studies, the rising medical interest in this new treatment correlates with a growing sensitivity to ethical questions. One of the most crucial concerns is that DBS might interfere with patients’ ability to make autonomous decisions. Thus, the goal of this article is to evaluate the impact DBS presumably has on the capacity to decide and act autonomously in patients with MDD in the light of the autonomy-undermining effects depression has itself. Following the chronological order of the procedure, special attention will first be paid to depression’s effects on patients’ capacity to make use of their free will in giving valid Informed Consent. We suggest that while the majority of patients with MDD appear capable of autonomous choices, as it is required for Informed Consent, they might still be unable to effectively act according to their own will whenever acting includes significant personal effort. In reducing disabling depressive symptoms like anhedonia and decrease of energy, DBS for treatment resistant MDD thus rather seems to be an opportunity to substantially increase autonomy than a threat to it.

  13. Chocolate spot of Eucalyptus

    OpenAIRE

    Cheewangkoon, R.; Groenewald, J.Z.; Hyde, K.D.; To-anun, C.; Crous, P.W.

    2012-01-01

    Chocolate Spot leaf disease of Eucalyptus is associated with several Heteroconium-like species of hyphomycetes that resemble Heteroconium s.str. in morphology. They differ, however, in their ecology, with the former being plant pathogenic, while Heteroconium s.str. is a genus of sooty moulds. Results of molecular analyses, inferred from DNA sequences of the large subunit (LSU) and internal transcribed spacers (ITS) region of nrDNA, delineated four Heteroconium-like species on Eucalyptus, name...

  14. High efficacy of first-line ART in a West African cohort, assessed by dried blood spot virological and pharmacological measurements.

    Science.gov (United States)

    de Truchis, Pierre; Lê, Minh Patrick; Daou, Mamane; Madougou, Boubacar; Nouhou, Yacouba; Moussa Saley, Sahada; Sani, Achirou; Adehossi, Eric; Rouveix, Elisabeth; Saidou, Mamadou; Peytavin, Gilles; Delaugerre, Constance

    2016-11-01

    The objectives of this study were to determine the rate of viral success in HIV-infected patients on first-line ART by the assessment of dried blood spot (DBS) viral load (VL) and to assess the performance of DBS sampling for VL measurement, genotypic resistance and antiretroviral concentration determinations. HIV-infected patients treated for >1 year with first-line ART in Niamey, Niger were included. VL based on nucleic acid sequence-based amplification (NASBA) assay (limit of quantification 100 copies/mL); antiretroviral concentrations were interpreted using standard plasma cut-offs after extrapolation of blood to plasma results. Median (IQR) results are presented. Two hundred and eighteen patients (61% women), aged 41 (34-46) years, with 138 (56-235) CD4 cells/mm 3 at baseline were included. After 4 (2-6) years of follow-up under therapy, CD4 gain was +197 (98-372) cells/mm 3 ; 81% had VL ART in Niger. Adherence was high, according to antiretroviral concentrations, and the majority of failures were explained by selection of drug resistance mutations detected in the DBS genotype. Using DBS might improve the assessment of ART failure in HIV-infected patients in low-income countries. © The Author 2016. Published by Oxford University Press on behalf of the British Society for Antimicrobial Chemotherapy. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.

  15. El spot electoral negativo

    Directory of Open Access Journals (Sweden)

    Palma Peña-Jiménez

    2011-01-01

    Full Text Available l spot político tiene durante la campaña un objetivo final inequívoco: la consecución del voto favorable. Se dirige al cuerpo electoral a través de la televisión y de Internet, y presenta, en muchos casos, un planteamiento negativo, albergando mensajes destinados a la crítica frontal contra el adversario, más que a la exposición de propuestas propias. Este artículo se centra en el análisis del spot electoral negativo, en aquellas producciones audiovisuales construidas sin más causa que la reprobación del contrincante. Se trata de vídeos que, lejos de emplearse en difundir las potencialidades de la organización y las virtudes de su candidato –además de su programa electoral–, consumen su tiempo en descalificar al oponente mediante la transmisión de mensajes, muchas veces, ad hominem. Repasamos el planteamiento negativo del spot electoral desde su primera manifestación, que en España data de 1996, año de emisión del conocido como vídeo del dóberman, sin olvidar otros ejemplos que completan el objeto de estudio.

  16. Do changes in natural gas futures prices influence changes in natural gas spot prices?

    International Nuclear Information System (INIS)

    Herbert, J.H.

    1993-01-01

    Data on natural gas futures and spot markets are examined to determine if variability in price on futures markets influences variability in price on spot markets. Using econometric techniques, it is found that changes in futures contract prices do not precede changes in spot market prices. (Author)

  17. The Spotting Distribution of Wildfires

    Directory of Open Access Journals (Sweden)

    Jonathan Martin

    2016-06-01

    Full Text Available In wildfire science, spotting refers to non-local creation of new fires, due to downwind ignition of brands launched from a primary fire. Spotting is often mentioned as being one of the most difficult problems for wildfire management, because of its unpredictable nature. Since spotting is a stochastic process, it makes sense to talk about a probability distribution for spotting, which we call the spotting distribution. Given a location ahead of the fire front, we would like to know how likely is it to observe a spot fire at that location in the next few minutes. The aim of this paper is to introduce a detailed procedure to find the spotting distribution. Most prior modelling has focused on the maximum spotting distance, or on physical subprocesses. We will use mathematical modelling, which is based on detailed physical processes, to derive a spotting distribution. We discuss the use and measurement of this spotting distribution in fire spread, fire management and fire breaching. The appendix of this paper contains a comprehensive review of the relevant underlying physical sub-processes of fire plumes, launching fire brands, wind transport, falling and terminal velocity, combustion during transport, and ignition upon landing.

  18. Application of dried blood spots to determine vitamin D status in a large nutritional study with unsupervised sampling: the Food4Me project.

    Science.gov (United States)

    Hoeller, Ulrich; Baur, Manuela; Roos, Franz F; Brennan, Lorraine; Daniel, Hannelore; Fallaize, Rosalind; Forster, Hannah; Gibney, Eileen R; Gibney, Mike; Godlewska, Magdalena; Hartwig, Kai; Kolossa, Silvia; Lambrinou, Christina P; Livingstone, Katherine M; Lovegrove, Julie A; Macready, Anna L; Manios, Yannis; Marsaux, Cyril F M; Martinez, J Alfredo; Celis-Morales, Carlos; Moschonis, George; Navas-Carretero, Santiago; O'Donovan, Clare B; San-Cristobal, Rodrigo; Saris, Wim H M; Surwiłło, Agnieszka; Traczyk, Iwona; Tsirigoti, Lydia; Walsh, Marianne C; Woolhead, Clara; Mathers, John C; Weber, Peter

    2016-01-28

    An efficient and robust method to measure vitamin D (25-hydroxy vitamin D3 (25(OH)D3) and 25-hydroxy vitamin D2 in dried blood spots (DBS) has been developed and applied in the pan-European multi-centre, internet-based, personalised nutrition intervention study Food4Me. The method includes calibration with blood containing endogenous 25(OH)D3, spotted as DBS and corrected for haematocrit content. The methodology was validated following international standards. The performance characteristics did not reach those of the current gold standard liquid chromatography-MS/MS in plasma for all parameters, but were found to be very suitable for status-level determination under field conditions. DBS sample quality was very high, and 3778 measurements of 25(OH)D3 were obtained from 1465 participants. The study centre and the season within the study centre were very good predictors of 25(OH)D3 levels (Pvitamin D status information in a large nutritional study.

  19. Use of dried-blood-spot samples and in-house assays to identify antiretroviral drug resistance in HIV-infected children in resource-constrained settings.

    Science.gov (United States)

    Ziemniak, Carrie; Mengistu, Yohannes; Ruff, Andrea; Chen, Ya-Hui; Khaki, Leila; Bedri, Abubaker; Simen, Birgitte B; Palumbo, Paul; Eshleman, Susan H; Persaud, Deborah

    2011-12-01

    Monitoring HIV drug resistance is an important component of the World Health Organization's global HIV program. HIV drug resistance testing is optimal with commercially available clinically validated test kits using plasma; however, that type of testing may not be feasible or affordable in resource-constrained settings. HIV genotyping from dried blood spots (DBS) with noncommercial (in-house) assays may facilitate the capture of HIV drug resistance outcomes in resource-constrained settings but has had varying rates of success. With in-house assays for HIV reverse transcriptase, we evaluated the yield of genotyping DBS samples collected from HIV-infected children who were enrolled in two clinical trials conducted in sub-Saharan Africa (median HIV viral load, 5.88 log(10) HIV RNA copies/ml; range, 4.04 to 6.99). Overall, HIV genotypes were obtained for 94 (89.5%) of 105 samples tested (95% and 84% from clinical trials #1 and #2, respectively); however, successful analysis of 15 (16.1%) of the 94 samples required repeat testing using a different set of primers on previously synthesized cDNA. The yield of genotyping was lower on the DBS that were stored suboptimally from clinical trial #2 (56% versus 88% for optimally stored). Concordance with plasma genotypes derived using a clinically validated, commercial kit-based assay (ViroSeq HIV-1 genotyping system) was also assessed in a subset of children with paired testing. For 34 samples with paired DBS and plasma genotypes, there was 100% concordance for major drug resistance mutations. DBS genotyping using in-house assays provides an alternative for antiretroviral drug resistance testing in children in resource-constrained regions but may require region-specific optimization before widespread use.

  20. Use of Dried-Blood-Spot Samples and In-House Assays To Identify Antiretroviral Drug Resistance in HIV-Infected Children in Resource-Constrained Settings ▿

    Science.gov (United States)

    Ziemniak, Carrie; Mengistu, Yohannes; Ruff, Andrea; Chen, Ya-Hui; Khaki, Leila; Bedri, Abubaker; Simen, Birgitte B.; Palumbo, Paul; Eshleman, Susan H.; Persaud, Deborah

    2011-01-01

    Monitoring HIV drug resistance is an important component of the World Health Organization's global HIV program. HIV drug resistance testing is optimal with commercially available clinically validated test kits using plasma; however, that type of testing may not be feasible or affordable in resource-constrained settings. HIV genotyping from dried blood spots (DBS) with noncommercial (in-house) assays may facilitate the capture of HIV drug resistance outcomes in resource-constrained settings but has had varying rates of success. With in-house assays for HIV reverse transcriptase, we evaluated the yield of genotyping DBS samples collected from HIV-infected children who were enrolled in two clinical trials conducted in sub-Saharan Africa (median HIV viral load, 5.88 log10 HIV RNA copies/ml; range, 4.04 to 6.99). Overall, HIV genotypes were obtained for 94 (89.5%) of 105 samples tested (95% and 84% from clinical trials #1 and #2, respectively); however, successful analysis of 15 (16.1%) of the 94 samples required repeat testing using a different set of primers on previously synthesized cDNA. The yield of genotyping was lower on the DBS that were stored suboptimally from clinical trial #2 (56% versus 88% for optimally stored). Concordance with plasma genotypes derived using a clinically validated, commercial kit-based assay (ViroSeq HIV-1 genotyping system) was also assessed in a subset of children with paired testing. For 34 samples with paired DBS and plasma genotypes, there was 100% concordance for major drug resistance mutations. DBS genotyping using in-house assays provides an alternative for antiretroviral drug resistance testing in children in resource-constrained regions but may require region-specific optimization before widespread use. PMID:21956987

  1. Hyperspectral analysis of columbia spotted frog habitat

    Science.gov (United States)

    Shive, J.P.; Pilliod, D.S.; Peterson, C.R.

    2010-01-01

    Wildlife managers increasingly are using remotely sensed imagery to improve habitat delineations and sampling strategies. Advances in remote sensing technology, such as hyperspectral imagery, provide more information than previously was available with multispectral sensors. We evaluated accuracy of high-resolution hyperspectral image classifications to identify wetlands and wetland habitat features important for Columbia spotted frogs (Rana luteiventris) and compared the results to multispectral image classification and United States Geological Survey topographic maps. The study area spanned 3 lake basins in the Salmon River Mountains, Idaho, USA. Hyperspectral data were collected with an airborne sensor on 30 June 2002 and on 8 July 2006. A 12-year comprehensive ground survey of the study area for Columbia spotted frog reproduction served as validation for image classifications. Hyperspectral image classification accuracy of wetlands was high, with a producer's accuracy of 96 (44 wetlands) correctly classified with the 2002 data and 89 (41 wetlands) correctly classified with the 2006 data. We applied habitat-based rules to delineate breeding habitat from other wetlands, and successfully predicted 74 (14 wetlands) of known breeding wetlands for the Columbia spotted frog. Emergent sedge microhabitat classification showed promise for directly predicting Columbia spotted frog egg mass locations within a wetland by correctly identifying 72 (23 of 32) of known locations. Our study indicates hyperspectral imagery can be an effective tool for mapping spotted frog breeding habitat in the selected mountain basins. We conclude that this technique has potential for improving site selection for inventory and monitoring programs conducted across similar wetland habitat and can be a useful tool for delineating wildlife habitats. ?? 2010 The Wildlife Society.

  2. Subtle Motion Analysis and Spotting using the Riesz Pyramid

    OpenAIRE

    Arango, Carlos,; Alata, Olivier; Emonet, Rémi; Legrand, Anne-Claire; Konik, Hubert

    2018-01-01

    International audience; Analyzing and temporally spotting motions which are almost invisible to the human eye might reveal interesting information about the world. However, detecting these events is difficult due to their short duration and low intensities. Taking inspiration from video magnification techniques, we design a workflow for analyzing and temporally spotting subtle motions based on the Riesz pyramid. In addition, we propose a filtering and masking scheme that segments motions of i...

  3. Modulation of Neuronal Activity in the Motor Thalamus during GPi-DBS in the MPTP Nonhuman Primate Model of Parkinson's Disease.

    Science.gov (United States)

    Muralidharan, Abirami; Zhang, Jianyu; Ghosh, Debabrata; Johnson, Mathew D; Baker, Kenneth B; Vitek, Jerrold L

    The motor thalamus is a key nodal point in the pallidothalamocortical "motor" circuit, which has been implicated in the pathogenesis of Parkinson's disease (PD) and other movement disorders. Although a critical structure in the motor circuit, the role of the motor thalamus in mediating the therapeutic effects of deep brain stimulation (DBS) of the internal segment of the globus pallidus (GPi) is not fully understood. To characterize the changes in neuronal activity in the pallidal (ventralis lateralis pars oralis (VLo) and ventralis anterior (VA)) and cerebellar (ventralis posterior lateralis pars oralis (VPLo)) receiving areas of the motor thalamus during therapeutic GPi DBS. Neuronal activity from the VA/VLo (n = 134) and VPLo (n = 129) was recorded from two non-human primates made parkinsonian using the neurotoxin 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine. For each isolated unit, one minute of data was recorded before, during and after DBS; a pulse width of 90 µs and a frequency of 135 Hz were used for DBS to replicate commonly used clinical settings. Stimulation amplitude was determined based on the parameters required to improve motor signs. Severity of motor signs was assessed using the UPDRS modified for nonhuman primates. Discharge rate, presence and characteristics of bursts, and oscillatory activity were computed and compared across conditions (pre-, during, and post-stimulation). Neurons in both the pallidal and cerebellar receiving areas demonstrated significant changes in their pattern of activity during therapeutic GPi DBS. A majority of the neurons in each nucleus were inhibited during DBS (VA/VLo: 47% and VPLo: 49%), while a smaller subset was excited (VA/VLo: 21% and VPLo: 17%). Bursts changed in structure, becoming longer in duration and both intra-burst and inter-spike intervals and variability were increased in both subnuclei. High frequency oscillatory activity was significantly increased during stimulation with 33% of VA

  4. Advances in spot curing technology

    International Nuclear Information System (INIS)

    Burga, R.

    1999-01-01

    A brief review of spot curing technology was presented. The process which a spot of energy of a specific wavelength bandwidth and irradiance is used to cause a coating, encapsulant or adhesive to change from a liquid to a solid state

  5. Spot Welding of Honeycomb Structures

    Science.gov (United States)

    Cohal, V.

    2017-08-01

    Honeycomb structures are used to prepare meals water jet cutting machines for textile. These honeycomb structures are made of stainless steel sheet thickness of 0.1-0.2 mm. Corrugated sheet metal strips are between two gears with special tooth profile. Hexagonal cells for obtaining these strips are welded points between them. Spot welding device is three electrodes in the upper part, which carries three welding points across the width of the strip of corrugated sheet metal. Spot welding device filled with press and advance mechanisms. The paper presents the values of the regime for spot welding.

  6. Streamlined determination of lysophosphatidylcholines in dried blood spots for newborn screening of X-linked adrenoleukodystrophy.

    Science.gov (United States)

    Turgeon, Coleman T; Moser, Ann B; Mørkrid, Lars; Magera, Mark J; Gavrilov, Dimitar K; Oglesbee, Devin; Raymond, Kimiyo; Rinaldo, Piero; Matern, Dietrich; Tortorelli, Silvia

    2015-01-01

    Pre-symptomatic hematopoietic stem cell transplantation is essential to achieve best possible outcomes for patients with the childhood cerebral form of X-linked adrenoleukodystrophy (X-ALD). We describe a high-throughput method for measurement of C20-C26 lysophosphatidylcholines (LPCs) and biochemical diagnosis of X-ALD using the same dried blood spots (DBS) routinely used for newborn screening. LPCs are extracted from 3-mm DBS punch with methanol containing an isotopically labeled LPC as internal standard. This extract is transferred to a 96-well plate, evaporated and then reconstituted in mobile phase for flow injection analysis tandem mass spectrometry (FIA-MS/MS) in selected reaction monitoring mode for measurement of four different LPCs (C20, C22, C24, C26) and the internal standard (d4-C26-LPC). Analysis time is 1.5min per sample. The mean CVs from the intra- and inter-assay experiments for LPCs were 6.3-15.1% for C20-LPC, 4.4-18.6% for C22-LPC and 4.5-14.3% for C24-LPC. Limits of detection were determined for C20-LPC (LOD=0.03μg/mL), C22-LPC (0.03μg/mL), C24-LPC (0.03μg/mL) and C26-LPC (0.01μg/mL). Reference ranges were established from DBS of 130 newborns and 20 adults. Samples of patients with X-ALD (n=16), peroxisomal biogenesis disorders (n=8), and X-ALD carriers (n=12) were analyzed blindly and all were correctly identified. Analysis of LPC species by FIA-MS/MS is a fast, simple and reliable method to screen for X-ALD and other peroxisomal disorders in DBS. To maximize specificity, abnormal results can be verified by a 2nd tier assay using LC-MS/MS. Copyright © 2014 Elsevier Inc. All rights reserved.

  7. Comparison of hot spot stress evaluation methods for welded structures

    Directory of Open Access Journals (Sweden)

    Jae-Myung Lee

    2010-12-01

    Full Text Available In this paper, different evaluation methods of Hot Spot Stresses (HSS have been applied to four different welded structure details in order to compare them and to illustrate their differences. The HSSs at failure-critical locations were calculated by means of a series of finite element analyses. There was good overall agreement between calculated and experimentally determined HSS on the critical locations. While different methods and procedures exist for the computation of the structural hot-spot stress at welded joints, the recommendations within the International Institute of Welding (IIW guideline concerning the ‘Hot Spot Stress’ approach were found to give good reference stress approximations for fatigue-loaded welded joints. This paper recommends and suggests an appropriate finite element modeling and hot spot stress evaluation technique based on round-robin stress analyses and experimental results of several welded structure details.

  8. Classification of Parking Spots Using Multilayer Perceptron Networks

    Directory of Open Access Journals (Sweden)

    FALCAO, H. S.

    2013-12-01

    Full Text Available This project intends to develop a prototype for the identification of free spots in open air parking area where there is a good aerial view without obstacles, allowing for the identification of occupied and free spots. We used image processing techniques and pattern recognition using Artificial Neural Networks (ANN. In order to help implement the prototype, we used Matlab. In order to simulate the parking area, we created a model so that we could acquire the images using a webcam, process them, train the neural network, classify the spots and finally, show the results. The results show that it is viable to apply pattern recognition through image capture to classify parking spots

  9. IMRT fluence map editing to control hot and cold spots

    International Nuclear Information System (INIS)

    Taylor Cook, J.; Tobler, Matt; Leavitt, Dennis D.; Watson, Gordon

    2005-01-01

    Manually editing intensity-modulated radiation therapy (IMRT) fluence maps effectively controls hot and cold spots that the IMRT optimization cannot control. Many times, re-optimizing does not reduce the hot spots or increase the cold spots. In fact, re-optimizing only places the hot and cold spots in different locations. Fluence-map editing provides manual control of dose delivery and provides the best treatment plan possible. Several IMRT treatments were planned using the Varian Eclipse planning system. We compare the effects on dose distributions between fluence-map editing and re-optimization, discuss techniques for fluence-map editing, and analyze differences between fluence editing on one beam vs. multiple beams. When editing a beam's fluence map, it is essential to choose a beam that least affects dose to the tumor and critical structures. Editing fluence maps gives an advantage in treatment planning and provides controlled delivery of IMRT dose

  10. Screening for adenylosuccinate lyase deficiency using tandem mass spectrometry analysis of succinylpurines in neonatal dried blood spots.

    Science.gov (United States)

    Zikanova, Marie; Krijt, Jakub; Skopova, Vaclava; Krijt, Matyas; Baresova, Veronika; Kmoch, Stanislav

    2015-01-01

    Stable isotope dilution coupled with liquid chromatography-tandem mass spectrometry (LC-MS/MS) is the sensitive method for screening for various inherited metabolic disorders using dried blood spots (DBSs). We present a method for LC-MS/MS determination of succinyladenosine (SAdo) and succinylaminoimidazole carboxamide riboside (SAICAr), biomarkers for adenylosuccinate lyase deficiency (dADSL), in DBS. SAICAr and SAdo were separated on a Symmetry-C18 column and detected using positive electrospray ionisation in selected reaction monitoring mode. The quantification was performed using the isotopically labelled internal standards SAdo-(13)C4 and SAICAr-(13)C4, which were prepared via ADSL-catalysed reactions of fumarate-(13)C4 with adenosine monophosphate and aminoimidazole carboxamide ribotide, respectively, and subsequent alkaline phosphatase-catalysed dephosphorylation of the resulting products. The detection of SAICAr and SAdo in DBS was linear over the range of 0-25μmol/L. The respective intra-assay and inter-assay imprecision values were less than 10.7% and 15.2% for SAICAr and 4.7% and 5.7% for SAdo. The recoveries from DBS spiked with different concentrations of SAICAr and SAdo were between 94% and 117%. The concentrations of SAICAr and SAdo were higher in the archived DBS from dADSL patients (SAICAr, 0.03-4.7μmol/L; SAdo, 1.5-21.3μmol/L; n=5) compared to those of the control subjects (SAICAr, 0-0.026μmol/L; SAdo, 0.06-0.14μmol/L; n=31), even after DBSs from dADSL patients were stored for 2-23years. We developed and validated a method of succinylpurine analysis in DBS that improves selective screening for dADSL in the paediatric population and may be used for retrospective diagnosis to aid the genetic counselling of affected families. Copyright © 2014 The Canadian Society of Clinical Chemists. Published by Elsevier Inc. All rights reserved.

  11. Dried blood spot analysis : facing new challenges

    NARCIS (Netherlands)

    Koster, Remco A; Touw, Daan J; Alffenaar, Jan-willem C

    2015-01-01

    Over the last decade, DBS analysis has gained popularity for TDM because it’s a patient friendly sampling proce- dure [1-4]. Additional advantages are prolonged sample stability, lower risk of infections and transportation at ambient temperature [1-3,5]. These advantages may fa- cilitate

  12. An LC-MS/MS-Based Method for the Quantification of Pyridox(am)ine 5'-Phosphate Oxidase Activity in Dried Blood Spots from Patients with Epilepsy.

    Science.gov (United States)

    Wilson, Matthew P; Footitt, Emma J; Papandreou, Apostolos; Uudelepp, Mari-Liis; Pressler, Ronit; Stevenson, Danielle C; Gabriel, Camila; McSweeney, Mel; Baggot, Matthew; Burke, Derek; Stödberg, Tommy; Riney, Kate; Schiff, Manuel; Heales, Simon J R; Mills, Kevin A; Gissen, Paul; Clayton, Peter T; Mills, Philippa B

    2017-09-05

    We report the development of a rapid, simple, and robust LC-MS/MS-based enzyme assay using dried blood spots (DBS) for the diagnosis of pyridox(am)ine 5'-phosphate oxidase (PNPO) deficiency (OMIM 610090). PNPO deficiency leads to potentially fatal early infantile epileptic encephalopathy, severe developmental delay, and other features of neurological dysfunction. However, upon prompt treatment with high doses of vitamin B 6 , affected patients can have a normal developmental outcome. Prognosis of these patients is therefore reliant upon a rapid diagnosis. PNPO activity was quantified by measuring pyridoxal 5'-phosphate (PLP) concentrations in a DBS before and after a 30 min incubation with pyridoxine 5'-phosphate (PNP). Samples from 18 PNPO deficient patients (1 day-25 years), 13 children with other seizure disorders receiving B 6 supplementation (1 month-16 years), and 37 child hospital controls (5 days-15 years) were analyzed. DBS from the PNPO-deficient samples showed enzyme activity levels lower than all samples from these two other groups as well as seven adult controls; no false positives or negatives were identified. The method was fully validated and is suitable for translation into the clinical diagnostic arena.

  13. 9 CFR 149.4 - Spot audit.

    Science.gov (United States)

    2010-01-01

    ... 9 Animals and Animal Products 1 2010-01-01 2010-01-01 false Spot audit. 149.4 Section 149.4... LIVESTOCK IMPROVEMENT VOLUNTARY TRICHINAE CERTIFICATION PROGRAM § 149.4 Spot audit. (a) In addition to regularly scheduled site audits, certified production sites will be subject to spot audits. (1) Random spot...

  14. The analysis of spot welding joints of steel sheets with closed profile by ultrasonic method

    OpenAIRE

    Dariusz Ulbrich; Jakub Kowalczyk; Marian Jósko; Jarosław Selech

    2015-01-01

    Resistance spot welding is widely used in the fabrication of vehicle bodies and parts of their equipment. The article presents the methodology and the results of non-destructive ultrasonic testing of resistance spot welded joints of thin steel sheet with closed profile. Non-destructive test results were verified on the basis of welded joint area after destructive testing. The obtained results were used to develop an assessment technique for spot welded joints of closed profile with steel shee...

  15. On the origin of delta spots

    International Nuclear Information System (INIS)

    Tang, F.

    1983-01-01

    Mount Wilson sunspot drawings from 1966 through 1980 were used in conjunction with Hα filtergrams from Big Bear Solar Observatory to examine the origin of delta spots, spots with bipolar umbrae within one penumbra. Of the six cases we studied, five were formed by the union of non-paired spots. They are either shoved into one another by two neighboring growing bipoles or by a new spot born piggy-back style on an existing spot of opposite polarity. Proper motions of the growing spots take on curvilinear paths around one another to avoid a collision. This is the shear motion observed in delta spots (Tanaka, 1979). In the remaining case, the delta spot was formed by spots that emerged as a pair. Our findings indicate no intrinsic differences in the formation or the behavior between delta spots of normal magnetic configuration. (orig.)

  16. A method for short term electricity spot price forecasting

    International Nuclear Information System (INIS)

    Koreneff, G.; Seppaelae, A.; Lehtonen, M.; Kekkonen, V.; Laitinen, E.; Haekli, J.; Antila, E.

    1998-01-01

    In Finland, the electricity market was de-regulated in November 1995. For the electricity purchase of power companies this has caused big changes, since the old tariff based contracts of bulk power supply have been replaced by negotiated bilateral short term contracts and by power purchase from the spot market. In the spot market, in turn, there are at the present two strong actors: The electricity exchange of Finland and the Nordic power pool which is run by the Swedish and Norwegian companies. Today, the power companies in Finland have short term trade with both of the electricity exchanges. The aim of this chapter is to present methods for spot price forecasting in the electricity exchange. The main focus is given to the Finnish circumstances. In the beginning of the presentation, the practices of the electricity exchange of Finland are described, and a brief presentation is given on the different contracts, or electricity products, available in the spot market. For comparison, the practices of the Nordic electricity exchange are also outlined. A time series technique for spot price forecasting is presented. The structure of the model is presented, and its validity is tested using real case data obtained from the Finnish power market. The spot price forecasting model is a part of a computer system for distribution energy management (DEM) in a de-regulated power market

  17. A method for short term electricity spot price forecasting

    Energy Technology Data Exchange (ETDEWEB)

    Koreneff, G.; Seppaelae, A.; Lehtonen, M.; Kekkonen, V. [VTT Energy, Espoo (Finland); Laitinen, E.; Haekli, J. [Vaasa Univ. (Finland); Antila, E. [ABB Transmit Oy (Finland)

    1998-08-01

    In Finland, the electricity market was de-regulated in November 1995. For the electricity purchase of power companies this has caused big changes, since the old tariff based contracts of bulk power supply have been replaced by negotiated bilateral short term contracts and by power purchase from the spot market. In the spot market, in turn, there are at the present two strong actors: The electricity exchange of Finland and the Nordic power pool which is run by the Swedish and Norwegian companies. Today, the power companies in Finland have short term trade with both of the electricity exchanges. The aim of this chapter is to present methods for spot price forecasting in the electricity exchange. The main focus is given to the Finnish circumstances. In the beginning of the presentation, the practices of the electricity exchange of Finland are described, and a brief presentation is given on the different contracts, or electricity products, available in the spot market. For comparison, the practices of the Nordic electricity exchange are also outlined. A time series technique for spot price forecasting is presented. The structure of the model is presented, and its validity is tested using real case data obtained from the Finnish power market. The spot price forecasting model is a part of a computer system for distribution energy management (DEM) in a de-regulated power market

  18. Field evaluation of a broadly sensitive HIV-1 in-house genotyping assay for use with both plasma and dried blood spot specimens in a resource-limited country.

    Science.gov (United States)

    Inzaule, Seth; Yang, Chunfu; Kasembeli, Alex; Nafisa, Lillian; Okonji, Jully; Oyaro, Boaz; Lando, Richard; Mills, Lisa A; Laserson, Kayla; Thomas, Timothy; Nkengasong, John; Zeh, Clement

    2013-02-01

    HIV-1 drug resistance (HIVDR) assays are important tools in clinical management of HIV-infected patients on antiretroviral therapy (ART) and surveillance of drug-resistant variants at population levels. The high cost associated with commercial assays hinders their use in resource-limited settings. We adopted and validated a low-cost in-house assay using 68 matched plasma and dried blood spot (DBS) samples with a median viral load (VL) of 58,187 copies/ml, ranging from 253 to 3,264,850 against the commercial assay ViroSeq. Results indicated that the in-house assay not only had a higher plasma genotyping rate than did ViroSeq (94% versus 78%) but also was able to genotype 89.5% (51/57) of the matched DBS samples with VLs of ≥ 1,000 copies/ml. The sensitivity in detecting DR mutations by the in-house assay was 98.29% (95% confidence interval [CI], 97.86 to 98.72) on plasma and 96.54 (95% CI, 95.93 to 97.15) on DBS, and the specificity was 99.97% (95% CI, 99.91 to 100.00) for both sample types compared to ViroSeq. The minor DR mutation differences detected by the in-house assay against ViroSeq did not result in clinical significance. In addition, cost analysis showed that the in-house assay could reduce the genotyping cost by about 60% for both plasma and DBS compared to ViroSeq. This field condition evaluation highlights the potential utility of a cost-effective, subtype-independent, in-house genotyping assay using both plasma and DBS specimens for HIVDR clinical monitoring and population-based surveillance in resource-limited settings.

  19. The effect of introducing point-of-care or dried blood spot analysis on the uptake of hepatitis C virus testing in high-risk populations: A systematic review of the literature.

    Science.gov (United States)

    Coats, Josh T; Dillon, John F

    2015-11-01

    Testing for hepatitis C virus (HCV) infection typically relies upon blood samples taken by traditional phlebotomy for laboratory processing. Novel testing methods, including using dried blood spots (DBS) and point-of-care (PoC) testing enable easier access to high risk populations who have less frequent contact with healthcare professionals. Many of these individuals have been exposed to HCV but have not previously been tested. We aimed to establish whether the availability of these novel testing methods increased either uptake of testing or the number of new diagnoses of HCV. The PubMed, Cochrane and SCOPUS databases were searched for terms relating to the study. References and associated bibliographies were also examined for further relevant articles. Studies were included if they contained quantitative data on frequency of testing and/or new diagnoses following the introduction of PoC and/or DBS testing of high-risk populations. Studies were then examined for findings and limitations and graded upon the quality of evidence provided. No studies were found which introduced PoC testing and determined its effect on frequency of testing or new diagnoses. Six studies were identified in which DBS testing was introduced and its effect evaluated. Two of the studies were randomised controlled trials, two were prospective cohort studies, one was an ecological study and one was a clinical audit. Populations studied included those attending substance misuse clinics, prisons and needle exchanges. Injection drug use was the commonest risk factor for HCV. Five of the six studies provided evidence that the introduction of DBS testing increased the number of tests, new diagnoses or both. Current evidence indicates that DBS testing availability may increase the uptake of testing for HCV in high-risk populations. There is currently no evidence regarding the efficacy of PoC testing in these populations. Copyright © 2015 Elsevier B.V. All rights reserved.

  20. Is this Red Spot the Blue Spot (locus ceruleum)?

    Energy Technology Data Exchange (ETDEWEB)

    Choe, Won Sick; Lee, Yu Kyung; Lee, Min Kyung; Hwang, Kyung Hoon [Gachon University Gil Hospital, Incheon (Korea, Republic of)

    2010-06-15

    The authors report brain images of 18F-FDG-PET in a case of schizophrenia. The images showed strikingly increased bilateral uptake in the locus ceruleum. The locus ceruleum is called the blue spot and known to be a center of the norepinephrinergic system.

  1. SPOTS Calibration Example

    Directory of Open Access Journals (Sweden)

    Patterson E.

    2010-06-01

    Full Text Available The results are presented using the procedure outlined by the Standardisation Project for Optical Techniques of Strain measurement to calibrate a digital image correlation system. The process involves comparing the experimental data obtained with the optical measurement system to the theoretical values for a specially designed specimen. The standard states the criteria which must be met in order to achieve successful calibration, in addition to quantifying the measurement uncertainty in the system. The system was evaluated at three different displacement load levels, generating strain ranges from 289 µstrain to 2110 µstrain. At the 289 µstrain range, the calibration uncertainty was found to be 14.1 µstrain, and at the 2110 µstrain range it was found to be 28.9 µstrain. This calibration procedure was performed without painting a speckle pattern on the surface of the metal. Instead, the specimen surface was prepared using different grades of grit paper to produce the desired texture.

  2. Objective evaluation of the sweet spot size in spatial sound reproduction using elevated loudspeakers

    DEFF Research Database (Denmark)

    Lacouture Parodi, Yesenia; Rubak, Per

    2010-01-01

    to the loudspeakers. This paper presents a follow-up evaluation of the performance of the three inversion techniques when the above mentioned conditions are relaxed. A setup to measure the sweet spot of different loudspeaker arrangements is described. The sweet spot was measured for 21 different loudspeaker...

  3. Silica Coated Paper Substrate for Paper-Spray Analysis of Therapeutic Drugs in Dried Blood Spots

    Science.gov (United States)

    Zhang, Zhiping; Xu, Wei; Manicke, Nicholas E.; Cooks, R. Graham; Ouyang, Zheng

    2011-01-01

    Paper spray is a newly developed ambient ionization method that has been applied for direct qualitative and quantitative analysis of biological samples. The properties of the paper substrate and spray solution have a significant impact on the release of chemical compounds from complex sample matrices, the diffusion of the analytes through the substrate, and the formation of ions for mass spectrometry analysis. In this study, a commercially available silica-coated paper was explored in an attempt to improve the analysis of therapeutic drugs in dried blood spots (DBS). The dichloromethane/isopropanol solvent has been identified as an optimal spray solvent for the analysis. The comparison was made with paper spray using chromatography paper as substrate with methanol/water as solvent for the analysis of verapamil, citalopram, amitriptyline, lidocaine and sunitinib in dried blood spots. It has been demonstrated the efficiency of recovery of the analytes was notably improved with the silica coated paper and the limit of quantitation (LOQ) for the drug analysis was 0.1 ng mL−1 using a commercial triple quadrupole mass spectrometer. The use of silica paper substrate also resulted in a sensitivity improvement of 5-50 fold in comparison with chromatography papers, including the Whatmann ET31 paper used for blood card. Analysis using a handheld miniature mass spectrometer Mini 11 gave LOQs of 10~20 ng mL−1 for the tested drugs, which is sufficient to cover the therapeutic ranges of these drugs. PMID:22145627

  4. Dressing percentage in Romanian spotted breed

    Directory of Open Access Journals (Sweden)

    eleonora nistor

    2013-05-01

    Full Text Available The purpose of this research was to determine whether there are significant differences in terms of carcass weight, forequarters, hindquarters and the dressing percentage among Romanian Spotted breed steers and first generation crossbreed obtained between Romanian Spotted and Holstein at slaughter age of 12 and 17 months respectively. Study was done on Romanian Spotted breed steer aged 12 months (36 heads and 17 months (19 heads; Romanian Spotted x Holstein first generation crossbreed of aged 12 months (29 heads and 17 months (20 heads. The Romanian Spotted breed steer, show superiority in terms of carcass weight compared to crossbreed of Romanian Spotted x Holstein, therefore this breed has a better suitability for fattening for meat. Regarding dressing percentage is higher in crossbreed of Romanian Spotted x Holstein compared with Romanian Spotted breed steers, but the difference is insignificant.

  5. Dominant white spotting in the Chinese hamster.

    Science.gov (United States)

    Henwood, C; Henwood, J; Robinson, R

    1987-01-01

    An autosomal dominant white spotting mutant is described for the Chinese hamster. The mutant gene is designated as dominant spot (symbol Ds). The homozygote DsDs is a prenatal lethal while the heterozygote Ds + displays white spotting. The expression of white is variable, ranging from a white forehead spot to extensive white on the body. The venter is invariably white. Growth appears to be normal and the fertility of both sizes shows no impairment.

  6. Laser Pyrometer For Spot Temperature Measurements

    Science.gov (United States)

    Elleman, D. D.; Allen, J. L.; Lee, M. C.

    1988-01-01

    Laser pyrometer makes temperature map by scanning measuring spot across target. Scanning laser pyrometer passively measures radiation emitted by scanned spot on target and calibrated by similar passive measurement on blackbody of known temperature. Laser beam turned on for active measurements of reflectances of target spot and reflectance standard. From measurements, temperature of target spot inferred. Pyrometer useful for non-contact measurement of temperature distributions in processing of materials.

  7. Determination of the size of X-ray tube focal spots: direct digitalization vs optical evaluation

    International Nuclear Information System (INIS)

    Furquim, Tania A.C.; Yanikian, Denise; Costa, Paulo R.

    1996-01-01

    A comparative study between standard techniques for evaluation of X-ray tubes focal spots and a newer one which uses digital resources for image acquisition is presented. Results from measurements by using both methods are presented

  8. A Drosophila wing spot test

    International Nuclear Information System (INIS)

    Ayaki, Toshikazu; Yoshikawa, Isao; Niikawa, Norio; Hoshi, Masaharu.

    1986-01-01

    A Drosophila wing spot test system was used to investigate the effects of low doses of X-rays, gamma rays, and both 2.3 and 14.1 MeV neutrons on somatic chromosome mutation (SCM) induction. The incidence of SCM was significantly increased with any type of radiation, with evident linear dose-response relationship within the range of 3 to 20 cGy. It was estimated that relative biological effectiveness value for SCM induction of 2.3 MeV neutrons to X-rays and gamma rays is much higher than that of 14.1 MeV neutrons to those photons (2.4 vs 8.0). The Drosophila wing spot test system seems to become a promising in vivo experimental method for higher animals in terms of the lack of necessity for a marvelously large number of materials required in conventional test system. (Namekawa, K.)

  9. Sweet Spots and Door Stops

    Science.gov (United States)

    Thompson, Michael; Tsui, Stella; Leung, Chi Fan

    2011-01-01

    A sweet spot is referred to in sport as the perfect place to strike a ball with a racquet or bat. It is the point of contact between bat and ball where maximum results can be produced with minimal effort from the hand of the player. Similar physics can be applied to the less inspiring examples of door stops; the perfect position of a door stop is…

  10. External quality assessment of cytomegalovirus DNA detection on dried blood spots

    Directory of Open Access Journals (Sweden)

    Binda Sandro

    2008-01-01

    Full Text Available Abstract Background Testing for viral DNA in neonatal blood dried on paper (DBS has proved a valid means of diagnosing congenital CMV infection with both clinical and epidemiological relevance. To assess the quality of the detection of CMV-DNA on DBS in laboratories performing this test a proficiency panel consisting of nine samples with two blood spots on each filter paper was produced and distributed. Six samples were derived from whole blood, negative for CMV DNA and antibody, and spiked with cell-grown CMV Towne in various concentrations (7.3 × 102 – 9.6 × 105 copies/ml, one was a CMV positive clinical specimen (3.9 × 106 copies/ml, and two samples were CMV-negative whole blood. Results The 27 responding laboratories from 14 countries submitted 33 datasets obtained by means of conventional PCR (n = 5 or real-time PCR (n = 28 technologies. A correct positive result was reported in at least 91% of datasets in samples with a viral load of 8.8 × 104 copies/ml or higher. However only 59% and 12% identified the 9.4 × 103 and 7.3 × 102 copies/ml samples, respectively, correctly as positive. False positive results were reported by 9% of laboratories and in 11% of datasets. Conclusion These results indicate a clear need for improvement of methods as sensitivity and false-positivity still appear to be a major problem in a considerable number of laboratories.

  11. Justifications shape ethical blind spots.

    Science.gov (United States)

    Pittarello, Andrea; Leib, Margarita; Gordon-Hecker, Tom; Shalvi, Shaul

    2015-06-01

    To some extent, unethical behavior results from people's limited attention to ethical considerations, which results in an ethical blind spot. Here, we focus on the role of ambiguity in shaping people's ethical blind spots, which in turn lead to their ethical failures. We suggest that in ambiguous settings, individuals' attention shifts toward tempting information, which determines the magnitude of their lies. Employing a novel ambiguous-dice paradigm, we asked participants to report the outcome of the die roll appearing closest to the location of a previously presented fixation cross on a computer screen; this outcome would determine their pay. We varied the value of the die second closest to the fixation cross to be either higher (i.e., tempting) or lower (i.e., not tempting) than the die closest to the fixation cross. Results of two experiments revealed that in ambiguous settings, people's incorrect responses were self-serving. Tracking participants' eye movements demonstrated that people's ethical blind spots are shaped by increased attention toward tempting information. © The Author(s) 2015.

  12. The analysis of spot welding joints of steel sheets with closed profile by ultrasonic method

    Directory of Open Access Journals (Sweden)

    Dariusz Ulbrich

    2015-11-01

    Full Text Available Resistance spot welding is widely used in the fabrication of vehicle bodies and parts of their equipment. The article presents the methodology and the results of non-destructive ultrasonic testing of resistance spot welded joints of thin steel sheet with closed profile. Non-destructive test results were verified on the basis of welded joint area after destructive testing. The obtained results were used to develop an assessment technique for spot welded joints of closed profile with steel sheet, which could be used in factories employing such joints. In addition, the article makes comparison between the costs of the developed assessment technique and currently used destructive method.

  13. Resistance Spot Welding of dissimilar Steels

    Directory of Open Access Journals (Sweden)

    Ladislav Kolařík

    2012-01-01

    Full Text Available This paper presents an analysis of the properties of resistance spot welds between low carbon steel and austenitic CrNi stainless steel. The thickness of the welded dissimilar materials was 2 mm. A DeltaSpot welding gun with a process tape was used for welding the dissimilar steels. Resistance spot welds were produced with various welding parameters (welding currents ranging from 7 to 8 kA. Light microscopy, microhardness measurements across the welded joints, and EDX analysis were used to evaluate the quality of the resistance spot welds. The results confirm the applicability of DeltaSpot welding for this combination of materials.

  14. A continuous scale-space method for the automated placement of spot heights on maps

    Science.gov (United States)

    Rocca, Luigi; Jenny, Bernhard; Puppo, Enrico

    2017-12-01

    Spot heights and soundings explicitly indicate terrain elevation on cartographic maps. Cartographers have developed design principles for the manual selection, placement, labeling, and generalization of spot height locations, but these processes are work-intensive and expensive. Finding an algorithmic criterion that matches the cartographers' judgment in ranking the significance of features on a terrain is a difficult endeavor. This article proposes a method for the automated selection of spot heights locations representing natural features such as peaks, saddles and depressions. A lifespan of critical points in a continuous scale-space model is employed as the main measure of the importance of features, and an algorithm and a data structure for its computation are described. We also introduce a method for the comparison of algorithmically computed spot height locations with manually produced reference compilations. The new method is compared with two known techniques from the literature. Results show spot height locations that are closer to reference spot heights produced manually by swisstopo cartographers, compared to previous techniques. The introduced method can be applied to elevation models for the creation of topographic and bathymetric maps. It also ranks the importance of extracted spot height locations, which allows for a variation in the size of symbols and labels according to the significance of represented features. The importance ranking could also be useful for adjusting spot height density of zoomable maps in real time.

  15. From IBS to DBS

    Directory of Open Access Journals (Sweden)

    Peter Benno MD, PhD

    2016-05-01

    Full Text Available Irritable bowel syndrome is a chronic gastrointestinal disorder characterized by abdominal pain and altered bowel habits in the absence of organic disease. We present 2 cases where diarrhea-predominant irritable bowel syndrome occurred in association with earlier intestinal infection or antibiotic treatment. Both were successfully treated with instillation of an anaerobic cultivated human intestinal microbiota. Thereafter, they were symptom free for at least 12 months. We now introduce the term dysbiotic bowel syndrome covering cases where a disturbed intestinal microbiota is assumed to be present. We recommend that restoration of the dysbiotic gut microbiota should be first-line treatment in these conditions.

  16. Watermarking spot colors in packaging

    Science.gov (United States)

    Reed, Alastair; Filler, TomáÅ.¡; Falkenstern, Kristyn; Bai, Yang

    2015-03-01

    In January 2014, Digimarc announced Digimarc® Barcode for the packaging industry to improve the check-out efficiency and customer experience for retailers. Digimarc Barcode is a machine readable code that carries the same information as a traditional Universal Product Code (UPC) and is introduced by adding a robust digital watermark to the package design. It is imperceptible to the human eye but can be read by a modern barcode scanner at the Point of Sale (POS) station. Compared to a traditional linear barcode, Digimarc Barcode covers the whole package with minimal impact on the graphic design. This significantly improves the Items per Minute (IPM) metric, which retailers use to track the checkout efficiency since it closely relates to their profitability. Increasing IPM by a few percent could lead to potential savings of millions of dollars for retailers, giving them a strong incentive to add the Digimarc Barcode to their packages. Testing performed by Digimarc showed increases in IPM of at least 33% using the Digimarc Barcode, compared to using a traditional barcode. A method of watermarking print ready image data used in the commercial packaging industry is described. A significant proportion of packages are printed using spot colors, therefore spot colors needs to be supported by an embedder for Digimarc Barcode. Digimarc Barcode supports the PANTONE spot color system, which is commonly used in the packaging industry. The Digimarc Barcode embedder allows a user to insert the UPC code in an image while minimizing perceptibility to the Human Visual System (HVS). The Digimarc Barcode is inserted in the printing ink domain, using an Adobe Photoshop plug-in as the last step before printing. Since Photoshop is an industry standard widely used by pre-press shops in the packaging industry, a Digimarc Barcode can be easily inserted and proofed.

  17. A prospective clinical trial to compare the performance of dried blood spots prenatal screening for Down's syndrome with conventional non-invasive testing technology.

    Science.gov (United States)

    Hu, Huiying; Jiang, Yulin; Zhang, Minghui; Liu, Shanying; Hao, Na; Zhou, Jing; Liu, Juntao; Zhang, Xiaojin; Ma, Liangkun

    2017-03-01

    To evaluate, side by side, the efficiency of dried blood spots (DBSs) against serum screening for Down's syndrome, and then, to construct a two-tier strategy by topping up the fetal cell-free DNA (cfDNA) secondary screening over the high-risk women marked by the primary blood testing to build a practical screening tactic to identify fetal Down's syndrome. One thousand eight hundred and thirty-seven low-risk Chinese women, with singleton pregnancy, were enrolled for the study. Alpha-fetoprotein and free beta human chorionic gonadotropin were measured for the serum as well as for the parallel DBS samples. Partial high-risk pregnant women identified by primary blood testing (n = 38) were also subject to the secondary cfDNA screening. Diagnostic amniocentesis was utilized to confirm the screening results. The true positive rate for Down's syndrome detection was 100% for both blood screening methods; however, the false-positive rate was 3.0% for DBS and 4.0% for serum screening, respectively. DBS correlated well with serum screening on Down's syndrome detection. Three out of 38 primary high-risk women displayed chromosomal abnormalities by cfDNA analysis, which were confirmed by amniocentesis. Either the true detection rate or the false-positive rate for Down's syndrome between DBS and the serum test is comparable. In addition, blood primary screening aligned with secondary cfDNA analysis, a "before and after" two-tier screening strategy, can massively decrease the false-positive rate, which, then, dramatically reduces the demand for invasive diagnostic operation. Impact statement Children born with Down's syndrome display a wide range of mental and physical disability. Currently, there is no effective treatment to ease the burden and anxiety of the Down's syndrome family and the surrounding society. This study is to evaluate the efficiency of dried blood spots against serum screening for Down's syndrome and to construct a two-tier strategy by topping up the fetal

  18. An LC–MS/MS-Based Method for the Quantification of Pyridox(am)ine 5′-Phosphate Oxidase Activity in Dried Blood Spots from Patients with Epilepsy

    Science.gov (United States)

    2017-01-01

    We report the development of a rapid, simple, and robust LC–MS/MS-based enzyme assay using dried blood spots (DBS) for the diagnosis of pyridox(am)ine 5′-phosphate oxidase (PNPO) deficiency (OMIM 610090). PNPO deficiency leads to potentially fatal early infantile epileptic encephalopathy, severe developmental delay, and other features of neurological dysfunction. However, upon prompt treatment with high doses of vitamin B6, affected patients can have a normal developmental outcome. Prognosis of these patients is therefore reliant upon a rapid diagnosis. PNPO activity was quantified by measuring pyridoxal 5′-phosphate (PLP) concentrations in a DBS before and after a 30 min incubation with pyridoxine 5′-phosphate (PNP). Samples from 18 PNPO deficient patients (1 day–25 years), 13 children with other seizure disorders receiving B6 supplementation (1 month–16 years), and 37 child hospital controls (5 days–15 years) were analyzed. DBS from the PNPO-deficient samples showed enzyme activity levels lower than all samples from these two other groups as well as seven adult controls; no false positives or negatives were identified. The method was fully validated and is suitable for translation into the clinical diagnostic arena. PMID:28782931

  19. Development and validation of an HPLC-MS/MS method for the analysis of dexamethasone from pig synovial fluid using dried matrix spotting.

    Science.gov (United States)

    Christianson, Chad D; Laine, Derek F; Zimmer, Jennifer Sd; Johnson, Casey Jl; Sheaff, Chrystal N; Carpenter, Anna; Needham, Shane R

    2010-11-01

    Dried matrix spot techniques were employed to validate an HPLC-MS/MS assay for the determination of dexamethasone in clear Yorkshire pig synovial fluid using 15 µl of sample. We have adopted the term dried matrix spot to indicate that the techniques used for dried blood spots can be applied to nonblood matrices. The dried matrix spot method employs a color-indicating process developed at Alturas Analytics that enhances the ability to analyze transparent fluids spotted onto collection paper by allowing the analyst to visually verify the location of the dried sample spot. The method was shown to be accurate (±4.3%) and precise (14.2% at the LLOQ and ≤10.0% at all other concentrations) across the dynamic range of the assay. The method shows the potential application of dried matrix spot techniques for the analysis of transparent biological fluids.

  20. Poisson-Spot Intensity Reduction with a Partially-Transparent Petal-Shaped Optical Mask

    Science.gov (United States)

    Shiri, Shahram; Wasylkiwskyj, Wasyl

    2013-01-01

    The presence of Poisson's spot, also known as the spot of Arago, formed along the optical axis in the geometrical shadow behind an obstruction, has been known since the 18th century. The presence of this spot can best be described as the consequence of constructive interference of light waves diffracted on the edge of the obstruction where its central position can··be determined by the symmetry of the object More recently, the elimination of this spot has received attention in the fields of particle physics, high-energy lasers, astronomy and lithography. In this paper, we introduce a novel, partially transparent petaled mask shape that suppresses the bright spot by up to 10 orders of magnitude in intensity, with powerful applications to many of the above fields. The optimization technique formulated in this design can identify mask shapes having partial transparency only near the petal tips.

  1. Oil futures and spot markets

    International Nuclear Information System (INIS)

    Samii, M.V.

    1992-01-01

    In the last decade, the oil futures market has risen to prominence and has become a major factor in influencing oil market psychology and the crude oil market. On a normal day, over 92 thousand contracts, the equivalent of 92 million barrels per day, change hands on the New York Mercantile Exchange, NYMEX. This market has provided a vehicle for hedging against risk. At the same time, it has also created opportunities for speculation. Those who previously were unable to participate in oil market transactions can now become involved through the futures market. The large number of participants in the future market and the availability of information has made this market more efficient and transparent, relative to the crude oil market. While there has been considerable in-depth analysis of other future markets, relatively little theoretical attention has focused on that of oil. This paper looks at the following issues. First, what is the relationship between futures and spot oil prices? And secondly, are futures prices a good predictor of spot crude prices in the future? (author)

  2. Integrating sustainable hunting in biodiversity protection in Central Africa: hot spots, weak spots, and strong spots.

    Directory of Open Access Journals (Sweden)

    John E Fa

    Full Text Available Wild animals are a primary source of protein (bushmeat for people living in or near tropical forests. Ideally, the effect of bushmeat harvests should be monitored closely by making regular estimates of offtake rate and size of stock available for exploitation. However, in practice, this is possible in very few situations because it requires both of these aspects to be readily measurable, and even in the best case, entails very considerable time and effort. As alternative, in this study, we use high-resolution, environmental favorability models for terrestrial mammals (N = 165 in Central Africa to map areas of high species richness (hot spots and hunting susceptibility. Favorability models distinguish localities with environmental conditions that favor the species' existence from those with detrimental characteristics for its presence. We develop an index for assessing Potential Hunting Sustainability (PHS of each species based on their ecological characteristics (population density, habitat breadth, rarity and vulnerability, weighted according to restrictive and permissive assumptions of how species' characteristics are combined. Species are classified into five main hunting sustainability classes using fuzzy logic. Using the accumulated favorability values of all species, and their PHS values, we finally identify weak spots, defined as high diversity regions of especial hunting vulnerability for wildlife, as well as strong spots, defined as high diversity areas of high hunting sustainability potential. Our study uses relatively simple models that employ easily obtainable data of a species' ecological characteristics to assess the impacts of hunting in tropical regions. It provides information for management by charting the geography of where species are more or less likely to be at risk of extinction from hunting.

  3. AN IMPROVED FUZZY CLUSTERING ALGORITHM FOR MICROARRAY IMAGE SPOTS SEGMENTATION

    Directory of Open Access Journals (Sweden)

    V.G. Biju

    2015-11-01

    Full Text Available An automatic cDNA microarray image processing using an improved fuzzy clustering algorithm is presented in this paper. The spot segmentation algorithm proposed uses the gridding technique developed by the authors earlier, for finding the co-ordinates of each spot in an image. Automatic cropping of spots from microarray image is done using these co-ordinates. The present paper proposes an improved fuzzy clustering algorithm Possibility fuzzy local information c means (PFLICM to segment the spot foreground (FG from background (BG. The PFLICM improves fuzzy local information c means (FLICM algorithm by incorporating typicality of a pixel along with gray level information and local spatial information. The performance of the algorithm is validated using a set of simulated cDNA microarray images added with different levels of AWGN noise. The strength of the algorithm is tested by computing the parameters such as the Segmentation matching factor (SMF, Probability of error (pe, Discrepancy distance (D and Normal mean square error (NMSE. SMF value obtained for PFLICM algorithm shows an improvement of 0.9 % and 0.7 % for high noise and low noise microarray images respectively compared to FLICM algorithm. The PFLICM algorithm is also applied on real microarray images and gene expression values are computed.

  4. Assessing Frogeye Leaf Spot Resistance on Recommended Soybean Cultivars

    Directory of Open Access Journals (Sweden)

    In Jeong Kang

    2015-09-01

    Full Text Available Soybean frogeye leaf spot caused by the fungus Cercospora sojina Hara, has known to lead a severe reduction of crop yield. Since frogeye leaf spot on soybean has recently become a serious problem in Korea, the susceptibility of recent recommended cultivars against C. sojina had been tested. To standardize the disease severity of soybean, the optimum sporulation condition of C. sojina and the disease index were established in this study. Sporulation was maximized on the 10% V8 juice agar with 12 h light and 12 h dark at 25°C. Spore suspension (105 spores/ml was sprayed on the leaves of soybean (V6 stage, and the disease responses to each isolate were evaluated on 28 days after inoculation. As a result, Daepung, Shinpaldal2ho, Yeonpung and Cheonga showed the resistance reaction to 8, 7, 6, 6 isolates of C. sojina, respectively, whereas Cheongja, Hwangkeum, Taekwang, Daewon, Cheonsang and Sinhwa showed the susceptible reaction to 8 isolates of C. sojina. Breeding the resistant soybean cultivars against C. sojina requires a uniform resistance for screening technique. The disease index of frogeye leaf spot on soybean developed in this study can be effectively used for the accurate field assay to select the frogeye leaf spot resistant soybean.

  5. Development of a novel biosensor based on a polypyrrole-dodecylbenzene sulphonate (PPy-DBS) film for the determination of amperometric cholesterol.

    Science.gov (United States)

    Özer, Bayram Oğuz; Çete, Servet

    2017-06-01

    Herein a novel amperometric biosensor based on a conducting polymer with anionic dopant modified electrode was successfully developed for detection of cholesterol. Polypyrrole is deposited on a platinum surface and the sodium dodecylbenzene sulphonate (DBS) ion-doped polypyrrole film was electrochemically prepared by scanning the electrode potential between -0.8 and +0.8 V at a scan rate of 20 mV/s. The present electrochemical biosensor was optimized in terms of working potential, number of cycles, concentrations of monomer, and anionic dopant. Cholesterol oxidase (ChOx) was physically entrapped in PPy-DBS to construct an amperometric cholesterol biosensor. Amperometric determination is based on the electrochemical detection of H 2 O 2 generated in the enzymatic reaction of cholesterol. Kinetic parameters, operational and storage stabilities, pH, and temperature dependencies were determined. Km and Imax were calculated as 0.11 μM and 0.967 nM/min, respectively. The operational stability results showed that 90.0% of the response current was retained after 30 activity assays. Morphology of electrodes was characterized by SEM and AFM. Additionally, contact angle measurements were made with 1 μL water of polymer film and enzyme electrode. As a result, the cholesterol biosensor suggested in this study is easy to prepare and is highly cost-effective. This composite (PPy-DBS) can supply a biocompatible and electrochemical microenvironment for immobilization of the enzyme, making this material a good candidate for the fabrication of highly sensitive and selective cholesterol biosensors.

  6. Photometric and Spectroscopic Survey of the Cluster [DBS2003] 156 Associated with the H II Region G331.1-0.5

    Science.gov (United States)

    Pinheiro, M. C.; Ortiz, R.; Abraham, Z.; Copetti, M. V. F.

    2016-05-01

    The Norma section of the Milky Way is especially interesting because it crosses three spiral arms: Sagittarius-Carina, Scutum-Crux and the Norma arm itself. Distance determinations of embedded young stellar clusters can contribute to define the spiral structure in this part of the Galaxy. However, spectrophotometric distances were obtained for only a few of these clusters in Norma. We present a photometric and spectroscopic study in the NIR of the [DBS2003] 156 stellar cluster, associated with the H II region G331.1-0.5. We aim to find the ionizing sources of the H II region and determine its distance. The cluster was observed in the J, H, and {K}{{s}} bands and eight potential massive stars were chosen among the detected sources according to color criteria; subsequent spectroscopy of these candidates was performed with the Ohio State Infrared Imager/Spectrometer spectrograph attached to the Southern Observatory for Astrophysical Research 4.1 m telescope. We identified and classified spectroscopically four early-type stars: IRS 176 (O8 V), IRS 308 (O-type), IRS 310 (O6 V), and IRS 71 (B1 Iab). Based on the proximity of IRS 176 and 308 with the radio continuum emission peaks and their relative positions with respect to the warm dust mid-infrared emission, we concluded that these two stars are the main ionizing sources of the H ii region G331.1-0.5. The mean spectrophotometric distance of IRS 176 and 310 of 3.38 ± 0.58 kpc is similar to that obtained in a previous work for two early-type stars of the neighbor cluster [DBS2003] 157 of 3.29 ± 0.58 kpc. The narrow range of radial velocities of radio sources in the area of the clusters [DBS2003] 156 and 157 and their similar visual extinction indicate that these clusters are physically associated. A common distance of 3.34 ± 0.34 kpc is derived for the system [DBS2003] 156 and 157. Based on observations obtained at the Southern Observatory for Astrophysical Research (SOAR), a joint project of the Ministério de Ci

  7. Modal testing and finite element model updating of laser spot welds

    Energy Technology Data Exchange (ETDEWEB)

    Husain, N Abu; Khodaparast, H Haddad; Snaylam, A; James, S; Sharp, M; Dearden, G; Ouyang, H, E-mail: h.ouyang@liverpool.ac.u [Department of Engineering, Harrison Hughes Building, University of Liverpool, L69 3GH (United Kingdom)

    2009-08-01

    Spot welds are used extensively in automotive engineering. One of the latest manufacturing techniques for producing spot welds is Laser Welding. Finite element (FE) modelling of laser welds for dynamic analysis is a research issue because of the complexity and uncertainty of the welds and thus formed structures. In this work, FE model of the welds is developed by employing CWELD element in NASTRAN and its feasibility for representing laser spot welds is investigated. The FE model is updated based on the measured modal data of hat-plate structures and cast as a structural minimisation problem by the application of NASTRAN codes.

  8. Hot spots of mutualistic networks.

    Science.gov (United States)

    Gilarranz, Luis J; Sabatino, Malena; Aizen, Marcelo A; Bascompte, Jordi

    2015-03-01

    Incorporating interactions into a biogeographical framework may serve to understand how interactions and the services they provide are distributed in space. We begin by simulating the spatiotemporal dynamics of realistic mutualistic networks inhabiting spatial networks of habitat patches. We proceed by comparing the predicted patterns with the empirical results of a set of pollination networks in isolated hills of the Argentinian Pampas. We first find that one needs to sample up to five times as much area to record interactions as would be needed to sample the same proportion of species. Secondly, we find that peripheral patches have fewer interactions and harbour less nested networks - therefore potentially less resilient communities - compared to central patches. Our results highlight the important role played by the structure of dispersal routes on the spatial distribution of community patterns. This may help to understand the formation of biodiversity hot spots. © 2014 The Authors. Journal of Animal Ecology © 2014 British Ecological Society.

  9. Cosmicflows-3: Cold Spot Repeller?

    Energy Technology Data Exchange (ETDEWEB)

    Courtois, Hélène M.; Graziani, Romain; Dupuy, Alexandra [University of Lyon, UCB Lyon 1, CNRS/IN2P3, IPN, Lyon (France); Tully, R. Brent [Institute for Astronomy, University of Hawaii, 2680 Woodlawn Drive, Honolulu, HI 96822 (United States); Hoffman, Yehuda [Racah Institute of Physics, Hebrew University, Jerusalem, 91904 (Israel); Pomarède, Daniel [Institut de Recherche sur les Lois Fondamentales de l’Univers, CEA, Université Paris-Saclay, F-91191 Gif-sur-Yvette (France)

    2017-09-20

    The three-dimensional gravitational velocity field within z ∼ 0.1 has been modeled with the Wiener filter methodology applied to the Cosmicflows-3 compilation of galaxy distances. The dominant features are a basin of attraction and two basins of repulsion. The major basin of attraction is an extension of the Shapley concentration of galaxies. One basin of repulsion, the Dipole Repeller, is located near the anti-apex of the cosmic microwave background dipole. The other basin of repulsion is in the proximate direction toward the “Cold Spot” irregularity in the cosmic microwave background. It has been speculated that a vast void might contribute to the amplitude of the Cold Spot from the integrated Sachs–Wolfe effect.

  10. Microstructure origin of hot spots in textured laser zone melting Bi-2212 monoliths

    Science.gov (United States)

    Lera, F.; Angurel, L. A.; Rojo, J. A.; Mora, M.; Recuero, S.; Arroyo, M. P.; Andrés, N.

    2005-11-01

    Hot spots are one of the main limitations in the development of large-scale high-power applications with superconducting materials. The application of digital speckle interferometry to detect inhomogeneous heating on ceramic superconductors allows the determining of a hot spot location in these materials before any damage is caused to the material. The technique detects deformations that are induced in the material due to dilatation, attaining a resolution of 0.45 µm /fringe. In this paper this technique has been applied to analyse the heating generation in Bi-2212 superconducting monoliths at room temperature and in operation conditions. In the first case a homogeneous heating is obtained, leading to a parallel fringe pattern. In the second case, a situation with an inhomogeneous heating origin has been detected. Once the position of this hot spot is determined, microstructure studies have been performed to determine which defects are responsible for hot spot generation.

  11. Microstructure origin of hot spots in textured laser zone melting Bi-2212 monoliths

    Energy Technology Data Exchange (ETDEWEB)

    Lera, F [Instituto de Ciencia de Materiales de Aragon (CSIC-Universidad de Zaragoza), c/ MarIa de Luna 3, 50018 Zaragoza (Spain); Angurel, L A [Instituto de Ciencia de Materiales de Aragon (CSIC-Universidad de Zaragoza), c/ MarIa de Luna 3, 50018 Zaragoza (Spain); Rojo, J A [Instituto de Ciencia de Materiales de Aragon (CSIC-Universidad de Zaragoza), c/ MarIa de Luna 3, 50018 Zaragoza (Spain); Mora, M [Instituto de Ciencia de Materiales de Aragon (CSIC-Universidad de Zaragoza), c/ MarIa de Luna 3, 50018 Zaragoza (Spain); Recuero, S [Instituto de Investigacion en IngenierIa de Aragon (I3A), Facultad de Ciencias, Universidad de Zaragoza, c/ Pedro Cerbuna 12, 50009 Zaragoza (Spain); Arroyo, M P [Instituto de Investigacion en IngenierIa de Aragon (I3A), Facultad de Ciencias, Universidad de Zaragoza, c/ Pedro Cerbuna 12, 50009 Zaragoza (Spain); Andres, N [Instituto de Investigacion en IngenierIa de Aragon (I3A), Facultad de Ciencias, Universidad de Zaragoza, c/ Pedro Cerbuna 12, 50009 Zaragoza (Spain)

    2005-11-15

    Hot spots are one of the main limitations in the development of large-scale high-power applications with superconducting materials. The application of digital speckle interferometry to detect inhomogeneous heating on ceramic superconductors allows the determining of a hot spot location in these materials before any damage is caused to the material. The technique detects deformations that are induced in the material due to dilatation, attaining a resolution of 0.45 {mu}m /fringe. In this paper this technique has been applied to analyse the heating generation in Bi-2212 superconducting monoliths at room temperature and in operation conditions. In the first case a homogeneous heating is obtained, leading to a parallel fringe pattern. In the second case, a situation with an inhomogeneous heating origin has been detected. Once the position of this hot spot is determined, microstructure studies have been performed to determine which defects are responsible for hot spot generation.

  12. Microstructure origin of hot spots in textured laser zone melting Bi-2212 monoliths

    International Nuclear Information System (INIS)

    Lera, F; Angurel, L A; Rojo, J A; Mora, M; Recuero, S; Arroyo, M P; Andres, N

    2005-01-01

    Hot spots are one of the main limitations in the development of large-scale high-power applications with superconducting materials. The application of digital speckle interferometry to detect inhomogeneous heating on ceramic superconductors allows the determining of a hot spot location in these materials before any damage is caused to the material. The technique detects deformations that are induced in the material due to dilatation, attaining a resolution of 0.45 μm /fringe. In this paper this technique has been applied to analyse the heating generation in Bi-2212 superconducting monoliths at room temperature and in operation conditions. In the first case a homogeneous heating is obtained, leading to a parallel fringe pattern. In the second case, a situation with an inhomogeneous heating origin has been detected. Once the position of this hot spot is determined, microstructure studies have been performed to determine which defects are responsible for hot spot generation

  13. Incident Infection and Resistance Mutation Analysis of Dried Blood Spots Collected in a Field Study of HIV Risk Groups, 2007-2010.

    Science.gov (United States)

    Wei, Xierong; Smith, Amanda J; Forrest, David W; Cardenas, Gabriel A; Beck, Dano W; LaLota, Marlene; Metsch, Lisa R; Sionean, Catlainn; Owen, S Michele; Johnson, Jeffrey A

    2016-01-01

    To assess the utility of cost-effective dried blood spot (DBS) field sampling for incidence and drug resistance surveillance of persons at high risk for HIV infection. We evaluated DBS collected in 2007-2010 in non-clinical settings by finger-stick from HIV-positive heterosexuals at increased risk of HIV infection (n = 124), men who have sex with men (MSM, n = 110), and persons who inject drugs (PWID, n = 58). Relative proportions of recent-infection findings among risk groups were assessed at avidity index (AI) cutoffs of ≤25%, ≤30%, and ≤35%, corresponding to an infection mean duration of recency (MDR) of 220.6, 250.4, and 278.3 days, respectively. Drug resistance mutation prevalence was compared among the risk groups and avidity indices. HIV antibody avidity testing of all self-reported ARV-naïve persons (n = 186) resulted in 9.7%, 11.3% and 14.0% with findings within the 221, 250, and 278-day MDRs, respectively. The proportion of ARV-naïve MSM, heterosexuals, and PWID reporting only one risk category who had findings below the suggested 30% AI was 23.1%, 6.9% and 3.6% (pinfection results than did heterosexuals and PWID. The disproportionately higher recent-infection findings for MSM as compared to PWID and heterosexuals increased as the MDR window increased. Unreported ARV use might explain greater recent-infection findings and drug resistance in this MSM population. DBS demonstrated utility in expanded HIV testing; however, optimal field handling is key to accurate recent-infection estimates.

  14. A pilot study using residual newborn dried blood spots to assess the potential role of cytomegalovirus and Toxoplasma gondii in the etiology of congenital hydrocephalus.

    Science.gov (United States)

    Simeone, Regina M; Rasmussen, Sonja A; Mei, Joanne V; Dollard, Sheila C; Frias, Jaime L; Shaw, Gary M; Canfield, Mark A; Meyer, Robert E; Jones, Jeffrey L; Lorey, Fred; Honein, Margaret A

    2013-07-01

    Congenital hydrocephalus is a condition characterized by accumulation of cerebrospinal fluid in the ventricles of the brain. Prenatal infections are risk factors for some birth defects. This pilot study investigated whether residual dried blood spots (DBS) could be used to assess infections as risk factors for birth defects by examining the associations between prenatal infection with Toxoplasma gondii (T. gondii) or cytomegalovirus (CMV) with congenital hydrocephalus. Case-infants with hydrocephalus (N=410) were identified among live-born infants using birth defects surveillance systems in California, North Carolina, and Texas. Control-infants without birth defects were randomly selected from the same geographic areas and time periods as case-infants (N=448). We tested residual DBS from case- and control-infants for T. gondii immunoglobulin M and CMV DNA. When possible, we calculated crude odds ratios (cORs) and confidence intervals (CIs). Evidence for prenatal T. gondii infection was more common among case-infants (1.2%) than control-infants (0%; p=0.11), and evidence for prenatal CMV infection was higher among case-infants (1.5%) than control-infants (0.7%; cOR: 2.3; 95% CI: 0.48, 13.99). Prenatal infections with T. gondii and CMV occurred more often among infants with congenital hydrocephalus than control-infants, although differences were not statistically significant. This pilot study highlighted some challenges in using DBS to examine associations between certain infections and birth defects, particularly related to reduced sensitivity and specimen storage conditions. Further study with increased numbers of specimens and higher quality specimens should be considered to understand better the contribution of these infections to the occurrence of congenital hydrocephalus. Copyright © 2013 Wiley Periodicals, Inc.

  15. Hot Spot Removal System: System description

    International Nuclear Information System (INIS)

    1997-09-01

    Hazardous wastes contaminated with radionuclides, chemicals, and explosives exist across the Department of Energy complex and need to be remediated due to environmental concerns. Currently, an opportunity is being developed to dramatically reduce remediation costs and to assist in the acceleration of schedules associated with these wastes by deploying a Hot Spot Removal System. Removing the hot spot from the waste site will remove risk driver(s) and enable another, more cost effective process/option/remedial alternative (i.e., capping) to be applied to the remainder of the site. The Hot Spot Removal System consists of a suite of technologies that will be utilized to locate and remove source terms. Components of the system can also be used in a variety of other cleanup activities. This Hot Spot Removal System Description document presents technologies that were considered for possible inclusion in the Hot Spot Removal System, technologies made available to the Hot Spot Removal System, industrial interest in the Hot Spot Removal System''s subsystems, the schedule required for the Hot Spot Removal System, the evaluation of the relevant technologies, and the recommendations for equipment and technologies as stated in the Plan section

  16. X-ray focal spot reconstruction by circular penumbra analysis—Application to digital radiography systems

    Energy Technology Data Exchange (ETDEWEB)

    Di Domenico, Giovanni, E-mail: didomenico@fe.infn.it; Cardarelli, Paolo; Taibi, Angelo; Gambaccini, Mauro [Dipartimento di Fisica e Scienze della Terra, Università degli Studi di Ferrara, via Saragat 1, FE I-44122, Italy and INFN - sezione di Ferrara, via Saragat 1, FE I-44122 (Italy); Contillo, Adriano [Dipartimento di Fisica e Scienze della Terra, Università degli Studi di Ferrara, via Saragat 1, FE I-44122 (Italy)

    2016-01-15

    Purpose: The quality of a radiography system is affected by several factors, a major one being the focal spot size of the x-ray tube. In fact, the measurement of such size is recognized to be of primary importance during acceptance tests and image quality evaluations of clinical radiography systems. The most common device providing an image of the focal spot emission distribution is a pin-hole camera, which requires a high tube loading in order to produce a measurable signal. This work introduces an alternative technique to obtain an image of the focal spot, through the processing of a single radiograph of a simple test object, acquired with a suitable magnification. Methods: The radiograph of a magnified sharp edge is a well-established method to evaluate the extension of the focal spot profile along the direction perpendicular to the edge. From a single radiograph of a circular x-ray absorber, it is possible to extract simultaneously the radial profiles of several sharp edges with different orientations. The authors propose a technique that allows to obtain an image of the focal spot through the processing of these radial profiles by means of a pseudo-CT reconstruction technique. In order to validate this technique, the reconstruction has been applied to the simulated radiographs of an ideal disk-shaped absorber, generated by various simulated focal spot distributions. Furthermore, the method has been applied to the focal spot of a commercially available mammography unit. Results: In the case of simulated radiographs, the results of the reconstructions have been compared to the original distributions, showing an excellent agreement for what regards both the overall distribution and the full width at half maximum measurements. In the case of the experimental test, the method allowed to obtain images of the focal spot that have been compared with the results obtained through standard techniques, namely, pin-hole camera and slit camera. Conclusions: The method was

  17. THE INFORMATION CONTENT IN ANALYTIC SPOT MODELS OF BROADBAND PRECISION LIGHT CURVES

    Energy Technology Data Exchange (ETDEWEB)

    Walkowicz, Lucianne M. [Department of Astrophysical Sciences, Princeton University, Peyton Hall, 4 Ivy Lane, Princeton, NJ 08534 (United States); Basri, Gibor [Astronomy Department, University of California at Berkeley, Hearst Field Annex, Berkeley, CA 94720 (United States); Valenti, Jeff A. [Space Telescope Science Institute, 3700 San Martin Dr., Baltimore, MD 21218 (United States)

    2013-04-01

    We present the results of numerical experiments to assess degeneracies in light curve models of starspots. Using synthetic light curves generated with the Cheetah starspot modeling code, we explore the extent to which photometric light curves constrain spot model parameters, including spot latitudes and stellar inclination. We also investigate the effects of spot parameters and differential rotation on one's ability to correctly recover rotation periods and differential rotation in the Kepler light curves. We confirm that in the absence of additional constraints on the stellar inclination, such as spectroscopic measurements of vsin i or occultations of starspots by planetary transits, the spot latitude and stellar inclination are difficult to determine uniquely from the photometry alone. We find that for models with no differential rotation, spots that appear on opposite hemispheres of the star may cause one to interpret the rotation period to be half of the true period. When differential rotation is included, the changing longitude separation between spots breaks the symmetry of the hemispheres and the correct rotation period is more likely to be found. The dominant period found via periodogram analysis is typically that of the largest spot. Even when multiple spots with periods representative of the star's differential rotation exist, if one spot dominates the light curve the signal of differential rotation may not be detectable from the periodogram alone. Starspot modeling is applicable to stars with a wider range of rotation rates than other surface imaging techniques (such as Doppler imaging), allows subtle signatures of differential rotation to be measured, and may provide valuable information on the distribution of stellar spots. However, given the inherent degeneracies and uncertainty present in starspot models, caution should be exercised in their interpretation.

  18. THE INFORMATION CONTENT IN ANALYTIC SPOT MODELS OF BROADBAND PRECISION LIGHT CURVES

    International Nuclear Information System (INIS)

    Walkowicz, Lucianne M.; Basri, Gibor; Valenti, Jeff A.

    2013-01-01

    We present the results of numerical experiments to assess degeneracies in light curve models of starspots. Using synthetic light curves generated with the Cheetah starspot modeling code, we explore the extent to which photometric light curves constrain spot model parameters, including spot latitudes and stellar inclination. We also investigate the effects of spot parameters and differential rotation on one's ability to correctly recover rotation periods and differential rotation in the Kepler light curves. We confirm that in the absence of additional constraints on the stellar inclination, such as spectroscopic measurements of vsin i or occultations of starspots by planetary transits, the spot latitude and stellar inclination are difficult to determine uniquely from the photometry alone. We find that for models with no differential rotation, spots that appear on opposite hemispheres of the star may cause one to interpret the rotation period to be half of the true period. When differential rotation is included, the changing longitude separation between spots breaks the symmetry of the hemispheres and the correct rotation period is more likely to be found. The dominant period found via periodogram analysis is typically that of the largest spot. Even when multiple spots with periods representative of the star's differential rotation exist, if one spot dominates the light curve the signal of differential rotation may not be detectable from the periodogram alone. Starspot modeling is applicable to stars with a wider range of rotation rates than other surface imaging techniques (such as Doppler imaging), allows subtle signatures of differential rotation to be measured, and may provide valuable information on the distribution of stellar spots. However, given the inherent degeneracies and uncertainty present in starspot models, caution should be exercised in their interpretation.

  19. Early Outcome of Subthalamic Nucleus Deep Brain Stimulation (STN-DBS in Advanced Parkinson Disease in First trial of Iranian Patients

    Directory of Open Access Journals (Sweden)

    Farzad Sina

    2009-11-01

    Full Text Available Background:To improve the debilitating features of Parkinson disease (PD different medical and surgical approaches are available. Subthalamic nucleus deep brain stimulation (STN-DBS was appeared to be a promising method during last two decades. This study aimed to evaluate early motor outcomes of this procedure in first trial of Iranian patients. Methods: Thirty-seven consecutive patients with advanced Parkinson disease with   poor response to common medical agents underwent bilateral STN-DBS. For assessment of motor function parameters Unified Parkinson Disease Rating scale III (UPDRS III was used. We compared total scores and subscores in three measurements performed as 1 preoperative off-medication, 2 preoperative on-medication and 3 six months postoperative on stimulation and on medication. Reduction in drug consumption was assessed with regard to administered doses of L-Dopa before and after surgery in stable states.Results: 26 men and 10 women with mean age of 50 years were evaluated (one person expired before 6-month follow-up. Mean total scores of UPDRSIII were calculated as 5.2±54.52, 2.88±18.22 and 3±12.8 in three measurements, respectively (p=0.003 .PostHoc analyses showed significant improvement among all measurements. Analysis of subscores also revealed significant amelioration in rigidity, resting tremor, hand movement, leg agility, finger tap and rapid alternating movement in on-medication phases of pre- and post-operation (all with p

  20. Merging DBS with viral vector or stem cell implantation: “hybrid” stereotactic surgery as an evolution in the surgical treatment of Parkinson's disease

    Directory of Open Access Journals (Sweden)

    Nathan C Rowland

    2016-01-01

    Full Text Available Parkinson's disease (PD is a complex neurodegenerative disorder that is currently managed using a broad array of symptom-based strategies. However, targeting its molecular origins represents the potential to discover disease-modifying therapies. Deep brain stimulation (DBS, a highly successful treatment modality for PD symptoms, addresses errant electrophysiological signaling pathways in the basal ganglia. In contrast, ongoing clinical trials testing gene and cell replacement therapies propose to protect or restore neuronal-based physiologic dopamine transmission in the striatum. Given promising new platforms to enhance target localization'such as interventional MRI-guided stereotaxy'the opportunity now exists to create hybrid therapies that combine DBS with gene therapy and/or cell implantation. In this mini-review, we discuss approaches used for central nervous system biologic delivery in PD patients in previous trials and propose a new set of strategies based on novel molecular targets. A multifaceted approach, if successful, may not only contribute to our understanding of PD pathology but could introduce a new era of disease modification.

  1. 7 CFR 28.415 - Low Middling Light Spotted Color.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 2 2010-01-01 2010-01-01 false Low Middling Light Spotted Color. 28.415 Section 28... Spotted Color. Low Middling Light Spotted Color is color which in spot or color, or both, is between Low Middling Color and Low Middling Spotted Color. ...

  2. 7 CFR 28.411 - Good Middling Light Spotted Color.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 2 2010-01-01 2010-01-01 false Good Middling Light Spotted Color. 28.411 Section 28... Light Spotted Color. Good Middling Light Spotted Color is color which in spot or color, or both, is between Good Middling Color and Good Middling Spotted Color. ...

  3. 7 CFR 28.413 - Middling Light Spotted Color.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 2 2010-01-01 2010-01-01 false Middling Light Spotted Color. 28.413 Section 28.413... Spotted Color. Middling Light Spotted Color is color which in spot or color, or both, is between Middling Color and Middling Spotted Color. ...

  4. 7 CFR 28.412 - Strict Middling Light Spotted Color.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 2 2010-01-01 2010-01-01 false Strict Middling Light Spotted Color. 28.412 Section 28... Light Spotted Color. Strict Middling Light Spotted Color is color which in spot or color, or both, is between Strict Middling Color and Strict Middling Spotted Color. ...

  5. Spotting a fake[Telling natural and synthetic diamonds apart

    Energy Technology Data Exchange (ETDEWEB)

    Lawson, S. [Diamond Trading Company, Maidenhead, Berkshire (United Kingdom)]. E-mail: simon.lawson@dtc.com

    2006-06-15

    Diamonds are highly prized for their dazzling appearance and hardness, but would you be able to spot one that had been created in the laboratory? Simon Lawson describes how physics-based techniques can distinguish between natural and synthetic stones. For the last 50 years or so we have been able to make synthetic diamonds that replicate the superlative physical and chemical properties of natural diamonds, and these are used largely for industrial applications. But in the mind of the consumer, there is far more to a diamond than its hardness or brilliance. Research commissioned by the Diamond Trading Company (DTC) has shown that 94% of women surveyed prefer natural diamonds over synthetic ones as a symbol of love, possibly as a result of the immense age of natural stones. One of the key research activities at the DTC is therefore to ensure that synthetic diamonds can be spotted easily. (U.K.)

  6. Hot Spots from Generated Defects in HMX Crystals

    Science.gov (United States)

    Sorensen, Christian; Cummock, Nicholas; O'Grady, Caitlin; Gunduz, I. Emre; Son, Steven

    2017-06-01

    There are several hot spot initiation mechanisms that have been proposed. However, direct observation of shock or impact compression of these mechanisms at macroscopic scale in explosives is difficult. Phase contrast imaging (PCI) may be applied to these systems. Here, high-speed video was used to record optical spectrum and for x-ray Phase Contrast Imaging (PCI) of shockwave interaction with low defect HMX crystals and crystals with engineered defects. Additionally, multiple crystals were arranged and observed under shock loading with PCI and optical high-speed video. Sample preparation techniques for generating voids and other engineered defects will be discussed. These methods include drilled holes and laser machined samples. Insight into hot spot mechanisms was obtained. Funding from ONR's PC@Xtreme MURI.

  7. Modeling electricity spot and futures price dependence: A multifrequency approach

    Science.gov (United States)

    Malo, Pekka

    2009-11-01

    Electricity prices are known to exhibit multifractal properties. We accommodate this finding by investigating multifractal models for electricity prices. In this paper we propose a flexible Copula-MSM (Markov Switching Multifractal) approach for modeling spot and weekly futures price dynamics. By using a conditional copula function, the framework allows us to separately model the dependence structure, while enabling use of multifractal stochastic volatility models to characterize fluctuations in marginal returns. An empirical experiment is carried out using data from Nord Pool. A study of volatility forecasting performance for electricity spot prices reveals that multifractal techniques are a competitive alternative to GARCH models. We also demonstrate how the Copula-MSM model can be employed for finding optimal portfolios, which minimizes the Conditional Value-at-Risk.

  8. Clinical relevance of the discrepancy in phenylalanine concentrations analyzed using tandem mass spectrometry compared with ion-exchange chromatography in phenylketonuria

    Directory of Open Access Journals (Sweden)

    Bridget M. Stroup

    2016-03-01

    Conclusion: Use of DBS analyzed using MS/MS to monitor blood phe concentrations in individuals with PKU yields significantly lower phe levels compared to plasma phe levels analyzed using IEC. Optimization of current testing methodologies for measuring phe in DBS, along with patient education regarding the appropriate technique for spotting blood on filter paper is needed to improve the accuracy of using DBS to measure phe concentrations in PKU management.

  9. Computational Modeling and Neuroimaging Techniques for Targeting during Deep Brain Stimulation

    Science.gov (United States)

    Sweet, Jennifer A.; Pace, Jonathan; Girgis, Fady; Miller, Jonathan P.

    2016-01-01

    Accurate surgical localization of the varied targets for deep brain stimulation (DBS) is a process undergoing constant evolution, with increasingly sophisticated techniques to allow for highly precise targeting. However, despite the fastidious placement of electrodes into specific structures within the brain, there is increasing evidence to suggest that the clinical effects of DBS are likely due to the activation of widespread neuronal networks directly and indirectly influenced by the stimulation of a given target. Selective activation of these complex and inter-connected pathways may further improve the outcomes of currently treated diseases by targeting specific fiber tracts responsible for a particular symptom in a patient-specific manner. Moreover, the delivery of such focused stimulation may aid in the discovery of new targets for electrical stimulation to treat additional neurological, psychiatric, and even cognitive disorders. As such, advancements in surgical targeting, computational modeling, engineering designs, and neuroimaging techniques play a critical role in this process. This article reviews the progress of these applications, discussing the importance of target localization for DBS, and the role of computational modeling and novel neuroimaging in improving our understanding of the pathophysiology of diseases, and thus paving the way for improved selective target localization using DBS. PMID:27445709

  10. HUBBLE FINDS NEW DARK SPOT ON NEPTUNE

    Science.gov (United States)

    2002-01-01

    NASA's Hubble Space Telescope has discovered a new great dark spot, located in the northern hemisphere of the planet Neptune. Because the planet's northern hemisphere is now tilted away from Earth, the new feature appears near the limb of the planet. The spot is a near mirror-image to a similar southern hemisphere dark spot that was discovered in 1989 by the Voyager 2 probe. In 1994, Hubble showed that the southern dark spot had disappeared. Like its predecessor, the new spot has high altitude clouds along its edge, caused by gasses that have been pushed to higher altitudes where they cool to form methane ice crystal clouds. The dark spot may be a zone of clear gas that is a window to a cloud deck lower in the atmosphere. Planetary scientists don t know how long lived this new feature might be. Hubble's high resolution will allow astronomers to follow the spot's evolution and other unexpected changes in Neptune's dynamic atmosphere. The image was taken on November 2, 1994 with Hubble's Wide Field Planetary Camera 2, when Neptune was 2.8 billion miles (4.5 billion kilometers) from Earth. Hubble can resolve features as small as 625 miles (1,000 kilometers) across in Neptune's cloud tops. Credit: H. Hammel (Massachusetts Institute of Technology) and NASA

  11. Pink Spot - Literature Review and Case Report.

    Science.gov (United States)

    Petel, Roy; Fuks, Anna

    Pink spots in teeth were first described by Mummery in 1920, and were related to resorption. Resorption is a pathologic process that often eludes the clinician with its varied etiologic factors and diverse clinical presentations. Resorption can be generally classified as internal and external resorption. Internal resorption has been described as a rare occurrence as compared to external resorption. This article describes a pink spot that was diagnosed as a progressing resorption process. Early diagnosis enabled a successful management of the lesion. Early diagnosis and treatment of an internal resorption, clinically seen as a pink spot, in a primary central incisor may prevent its fast progress and subsequent loss.

  12. A selective detection of lysophosphatidylcholine in dried blood spots for diagnosis of adrenoleukodystrophy by LC-MS/MS

    Directory of Open Access Journals (Sweden)

    Ryuichi Mashima

    2016-06-01

    Full Text Available X-linked adrenoleukodystrophy (X-ALD is a rare inherited metabolic disorder characterized by an impaired beta-oxidation of very long chain fatty acids in the peroxisomes. Recent studies have suggested that 1-hexacosanoyl-2-hydroxy-sn-glycero-3-phosphocholine (Lyso-PC 26:0 can be a sensitive biomarker for X-ALD. Although approximately 10-fold increase in the concentration of Lyso-PC 26:0 in DBSs from X-ALD-affected individuals were reported, whether the carriers might be distinguished from the healthy controls remained unclear. To address this question, we have validated previously developed LC-MS/MS-based analytical procedures using QC DBS. We found that the recovery of Lyso-PC 26:0 from the QC DBSs was 73.6 ± 0.3% when 2 μM of Lyso-PC 26:0 was spiked into the blood. Based on this result, the amounts of Lyso-PC 26:0 in the controls and ALD-affected individuals were 0.090 ± 0.004 (n = 11 and 1.078 ± 0.217 (n = 4 pmol/DBS, respectively. Interestingly, the concentration of Lyso-PC 26:0 in the carriers were 0.548 ± 0.095 pmol/DBS (n = 3, indicating that the carriers and the healthy controls can be distinguished. These results suggest that LC-MS/MS-based technique can be used for the detection of asymptomatic carriers and X-ALD-affected subjects in the newborn screening.

  13. Diagnosis of immunodeficiency caused by a purine nucleoside phosphorylase defect by using tandem mass spectrometry on dried blood spots.

    Science.gov (United States)

    la Marca, Giancarlo; Canessa, Clementina; Giocaliere, Elisa; Romano, Francesca; Malvagia, Sabrina; Funghini, Silvia; Moriondo, Maria; Valleriani, Claudia; Lippi, Francesca; Ombrone, Daniela; Della Bona, Maria Luisa; Speckmann, Carsten; Borte, Stephan; Brodszki, Nicholas; Gennery, Andrew R; Weinacht, Katja; Celmeli, Fatih; Pagel, Julia; de Martino, Maurizio; Guerrini, Renzo; Wittkowski, Helmut; Santisteban, Ines; Bali, Pawan; Ikinciogullari, Aydan; Hershfield, Michael; Notarangelo, Luigi D; Resti, Massimo; Azzari, Chiara

    2014-07-01

    Purine nucleoside phosphorylase (PNP) deficiency is a rare form of autosomal recessive combined primary immunodeficiency caused by a enzyme defect leading to the accumulation of inosine, 2'-deoxy-inosine (dIno), guanosine, and 2'-deoxy-guanosine (dGuo) in all cells, especially lymphocytes. Treatments are available and curative for PNP deficiency, but their efficacy depends on the early approach. PNP-combined immunodeficiency complies with the criteria for inclusion in a newborn screening program. This study evaluate whether mass spectrometry can identify metabolite abnormalities in dried blood spots (DBSs) from affected patients, with the final goal of individuating the disease at birth during routine newborn screening. DBS samples from 9 patients with genetically confirmed PNP-combined immunodeficiency, 10,000 DBS samples from healthy newborns, and 240 DBSs from healthy donors of different age ranges were examined. Inosine, dIno, guanosine, and dGuo were tested by using tandem mass spectrometry (TMS). T-cell receptor excision circle (TREC) and kappa-deleting recombination excision circle (KREC) levels were evaluated by using quantitative RT-PCR only for the 2 patients (patients 8 and 9) whose neonatal DBSs were available. Mean levels of guanosine, inosine, dGuo, and dIno were 4.4, 133.3, 3.6, and 3.8 μmol/L, respectively, in affected patients. No indeterminate or false-positive results were found. In patient 8 TREC levels were borderline and KREC levels were abnormal; in patient 9 TRECs were undetectable, whereas KREC levels were normal. TMS is a valid method for diagnosis of PNP deficiency on DBSs of affected patients at a negligible cost. TMS identifies newborns with PNP deficiency, whereas TREC or KREC measurement alone can fail. Copyright © 2014 American Academy of Allergy, Asthma & Immunology. Published by Mosby, Inc. All rights reserved.

  14. Isolation of human genomic DNA for genetic analysis from premature neonates: a comparison between newborn dried blood spots, whole blood and umbilical cord tissue

    Science.gov (United States)

    2013-01-01

    Background Genotyping requires biological sample collection that must be reliable, convenient and acceptable for patients and clinicians. Finding the most optimal procedure of sample collection for premature neonates who have a very limited blood volume is a particular challenge. The aim of the current study was to evaluate the use of umbilical cord (UC) tissue and newborn dried blood spot (DBS)-extracted genomic DNA (gDNA) as an alternative to venous blood-derived gDNA from premature neonates for molecular genetic analysis. All samples were obtained from premature newborn infants between 24-32 weeks of gestation. Paired blood and UC samples were collected from 31 study participants. gDNA was extracted from ethylenediaminetetraacetic acid (EDTA) anticoagulant-treated blood samples (~500 μl) and newborn DBSs (n = 723) using QIAamp DNA Micro kit (Qiagen Ltd., Crawley, UK); and from UC using Qiagen DNAeasy Blood and Tissue kit (Qiagen Ltd., Crawley, UK). gDNA was quantified and purity confirmed by measuring the A260:A280 ratio. PCR amplification and pyrosequencing was carried out to determine suitability of the gDNA for molecular genetic analysis. Minor allele frequency of two unrelated single nucleotide polymorphisms (SNPs) was calculated using the entire cohort. Results Both whole blood samples and UC tissue provided good quality and yield of gDNA, which was considerably less from newborn DBS. The gDNA purity was also reduced after 3 years of storage of the newborn DBS. PCR amplification of three unrelated genes resulted in clear products in all whole blood and UC samples and 86%-100% of newborn DBS. Genotyping using pyrosequencing showed 100% concordance in the paired UC and whole blood samples. Minor allele frequencies of the two SNPs indicated that no maternal gDNA contamination occurred in the genotyping of the UC samples. Conclusions gDNAs from all three sources are suitable for standard PCR and pyrosequencing assays. Given that UC provide good quality

  15. Material Characterization of Dissimilar Friction Stir Spot Welded Aluminium and Copper Alloy

    Science.gov (United States)

    Sanusi, K. O.; Akinlabi, E. T.

    2017-08-01

    In this research study, material characterization of dissimilar friction stir spot welded Aluminium and Copper was evaluated. Rotational speeds of 800 rpm and transverse speeds of 50 mm/min, 150 mm/min and 250 mm/min were used. The total numbers of samples evaluated were nine altogether. The spot welds were characterised by microstructure characterization using optical microscope (OEM) and scanning electron microscopy technique (SEM) by observing the evolution of the microstructure across the weld’s cross-section. lap-shear test of the of the spot weld specimens were also done. From the results, it shows that welding of metals and alloys using Friction stir spot welding is appropriate and can be use in industrial applications.

  16. FORECASTING ELECTRICITY PRICES IN DEREGULATED WHOLESALE SPOT ELECTRICITY MARKET - A REVIEW

    Directory of Open Access Journals (Sweden)

    Girish Godekere Panchakshara Murthy,

    2014-01-01

    Full Text Available In the new framework of competitive electricity markets, all power market participants need accurate price forecasting tools. Electricity price forecasts characterize significant information that can help captive power producer, independent power producer, power generation companies, power distribution companies or open access consumers in careful planning of their bidding strategies for maximizing their profits, benefits and utilities from long term, medium term and short term perspective. Short term spot electricity price forecasting techniques are either inspired from electrical engineering literature (i.e. load forecasting or from economics literature (i.e. game theory models and the time-series econometric models. In this study we investigate the emergence of spot electricity markets with particular emphasis on Indian electricity market which has never been done before and review selected finance and econometrics inspired literature and models for forecasting electricity spot prices in deregulated wholesale spot electricity markets.

  17. Reactivity in Rapidly Collected Hygiene and Toilet Spot Check Measurements: A Cautionary Note for Longitudinal Studies

    Science.gov (United States)

    Arnold, Benjamin F.; Khush, Ranjiv S.; Ramaswamy, Padmavathi; Rajkumar, Paramasivan; Durairaj, Natesan; Ramaprabha, Prabhakar; Balakrishnan, Kalpana; Colford Jr., John M.

    2015-01-01

    Discreet collection of spot check observations to measure household hygiene conditions is a common measurement technique in epidemiologic studies of hygiene in low-income countries. The objective of this study was to determine whether the collection of spot check observations in longitudinal studies could itself induce reactivity (i.e., change participant behavior). We analyzed data from a 12-month prospective cohort study in rural Tamil Nadu, India that was conducted in the absence of any hygiene or toilet promotion activities. Our data included hygiene and toilet spot checks from 10,427 household visits. We found substantial evidence of participant reactivity to spot check observations of hygiene practices that were easy to modify on short notice. For example, soap observed at the household's primary handwashing location increased from 49% at enrollment to 81% by the fourth visit and remained at or above 77% for the remainder of the study. PMID:25385856

  18. Computational analysis of hot-spot formation by quasi-steady deformation waves in porous explosive

    Science.gov (United States)

    Gilbert, John; Chakravarthy, Sunada; Gonthier, Keith A.

    2013-05-01

    The impact and shock sensitivity of porous (granular) high-explosives is related to the formation of small mass regions of elevated temperature within the material called hot-spots by dissipative mechanisms such as plastic and friction work. Because of their small size, hot-spots are difficult to experimentally interrogate, particularly for high volumetric strain rates (ɛ˙V>10,000 s-1). In this study, simulations are performed for large ensembles of deformable particles (≈4000 particles) using a combined finite and discrete element technique to characterize statistical distributions of hot-spot intensity, geometry, and spatial proximity within and behind quasi-steady, piston supported uniaxial waves in granular HMX (C4H8N8O8). Emphasis is placed on examining how the material's initial particle packing density, characterized by its effective solid volume fraction ϕ¯s ,0, affects hot-spot statistics for pressure dominated waves corresponding to piston speeds within the range 300≤Up≤500 m /s. Predictions indicate that hot-spot intensity is only marginally affected by initial porosity (1-ϕ¯s ,0) for all piston speeds, whereas hot-spot size, number density, volume fraction, and volume specific surface area appreciably increase with porosity and exponentially increase with piston speed. Minor variations in particle shape are predicted to be largely inconsequential. Joint distributions of hot-spot intensity and size are combined with thermal explosion data to identify and examine critical hot-spots that quickly react behind waves. These results indicate that the observed increase in sensitivity with initial porosity for sustained loading is likely due to an increase in hot-spot size and number rather than intensity.

  19. Telemetry-based mortality estimates of juvenile spot in two North Carolina estuarine creeks

    Science.gov (United States)

    Friedl, Sarah E.; Buckel, Jeffery A.; Hightower, Joseph E.; Scharf, Frederick S.; Pollock, Kenneth H.

    2013-01-01

    We estimated natural mortality rates (M) of age-1 Spot Leiostomus xanthurus by using a sonic telemetry approach. Sonic transmitters were surgically implanted into a total of 123 age-1 Spot in two North Carolina estuarine creeks during spring 2009 and 2010, and the fish were monitored by using a stationary acoustic receiver array and manual tracking. Fates of telemetered Spot were inferred based on telemetry information from estimated locations and swimming speeds. Potential competitors of age-1 Spot were assessed through simultaneous otter trawl sampling, while potential predators of Spot were collected using gill nets and trammel nets. The number of inferred natural mortalities was zero in 2009 (based on 29 telemetered Spot at risk) and four in 2010 (based on 52 fish at risk), with fish being at risk for up to about 70 d each year. Catches of potential competitors or predators did not differ between years, and age-1 Spot were not found in analyzed stomach contents of potential predators. Our estimated 30-d M of 0.03 (95% credible interval = 0.01–0.07) was lower than that predicted from weight-based (M = 0.07) and life-history-based (M = 0.06–0.36) estimates. Our field-based estimate of M for age-1 Spot in this estuarine system can assist in the assessment and management of Spot by allowing a direct comparison with M-values predicted from fish size or life history characteristics. The field telemetry and statistical analysis techniques developed here provide guidance for future telemetry studies of relatively small fish in open, dynamic habitat systems, as they highlight strengths and weaknesses of using a telemetry approach to estimate M.

  20. Asparagus Beetle and Spotted Asparagus Beetle

    OpenAIRE

    Hodgson, Erin W.; Drost, Dan

    2007-01-01

    Asparagus beetle, Crioceris asparagi, and spotted asparagus beetle, C. duodecimpunctata are leaf beetles in the family Chrysomelidae. These beetles feed exclusively on asparagus and are native to Europe. Asparagus beetle is the more economically injurious of the two species.

  1. Detecting Blind Spot By Using Ultrasonic Sensor

    Directory of Open Access Journals (Sweden)

    T. S. Ajay

    2015-08-01

    Full Text Available Safety remains a top concern for automobile industries and new-car shoppers. Detection of Blind Spots is a major concern for safety issues. So automobiles have been constantly updating their products with new technologies to detect blind spots so that they can add more safety to the vehicle and also reduce the road accidents. Almost 1.5 million people die in road accidents each year. Blind spot of an automobile is the region of the vehicle which cannot be observed properly while looking either through side or rear mirror view. To meet the above requirements this paper describes detecting blind spot by using ultrasonic sensor and controlling the direction of car by automatic steering. The technology embedded in the system is capable of automatically steer the vehicle away from an obstacle if the system determines that a collision is impending or if the vehicle is in the vicinity of our car.

  2. How Many Spots Does a Cheetah Have?

    Science.gov (United States)

    Reed, Kristine M.

    2000-01-01

    Describes first grade students' mathematical investigation of the number of spots on a cheetah. The exploration of counting and estimation strategies that grew from the investigation gives evidence that mathematicians come in all ages. (ASK)

  3. Plasma spot welding of ferritic stainless steels

    International Nuclear Information System (INIS)

    Lesnjak, A.; Tusek, J.

    2002-01-01

    Plasma spot wedding of ferritic stainless steels studied. The study was focused on welding parameters, plasma and shieldings and the optimum welding equipment. Plasma-spot welded overlap joints on a 0.8 mm thick ferritic stainless steel sheet were subjected to a visual examination and mechanical testing in terms of tension-shear strength. Several macro specimens were prepared Plasma spot welding is suitable to use the same gas as shielding gas and as plasma gas , i. e. a 98% Ar/2% H 2 gas mixture. Tension-shear strength of plasma-spot welded joint was compared to that of resistance sport welded joints. It was found that the resistance welded joints withstand a somewhat stronger load than the plasma welded joints due to a large weld sport diameter of the former. Strength of both types of welded joints is approximately the same. (Author) 32 refs

  4. A telemetry experiment on spotted grunter Pomadasys ...

    African Journals Online (AJOL)

    associated fish in South Africa was investigated by conducting a tracking experiment on spotted grunter Pomadasys commersonnii in the East Kleinemonde Estuary. The telemetry equipment comprised two VEMCO V8 transmitters and a ...

  5. Measuring microfocus focal spots using digital radiography

    Energy Technology Data Exchange (ETDEWEB)

    Fry, David A [Los Alamos National Laboratory

    2009-01-01

    Measurement of microfocus spot size can be important for several reasons: (1) Quality assurance during manufacture of microfocus tubes; (2) Tracking performance and stability of microfocus tubes; (3) Determining magnification (especially important for digital radiography where the native spatial resolution of the digital system is not adequate for the application); (4) Knowledge of unsharpness from the focal spot alone. The European Standard EN 12543-5 is based on a simple geometrical method of calculating focal spot size from unsharpness of high magnification film radiographs. When determining microfocus focal spot dimensions using unsharpness measurements both signal-to-noise (SNR) and magnification can be important. There is a maximum accuracy that is a function of SNR and therefore an optimal magnification. Greater than optimal magnification can be used but it will not increase accuracy.

  6. X-ray spot film device

    International Nuclear Information System (INIS)

    Pury, T.; Tsen, M.L.S.; Gray, F.L.; Stehr, R.E.; Konle, R.L.

    1981-01-01

    Improvements are described in an X-ray spot film device which is used in conjunction with an X-ray table to make a selected number of radiographic exposures on a single film and to perform fluoroscopic examinations. To date, the spot film devices consist of two X-ray field defining masks, one of which is moved manually. The present device is more convenient to use and speeds up the procedure. (U.K.)

  7. Postprandial Insulin and Triglycerides after Different Breakfast Meal Challenges: Use of Finger Stick Capillary Dried Blood Spots to Study Postprandial Dysmetabolism

    Science.gov (United States)

    Kapur, Sonia; Groves, Margaret N.; Zava, David T.; Kapur, Sanjay

    2010-01-01

    Background High levels of insulin and lipids following a meal are recognized risk factors for atherosclerosis. Monitoring such risk factors in the general population is hampered by the inconvenience of venipuncture blood collection, particularly for both premeal and postmeal analyses. This study examined insulin and triglyceride levels in dried blood spots (DBSs) collected after different breakfast meal challenges to assess the potential of this method for risk assessment. Methods Glucose levels were measured using a glucose meter, and insulin and triglycerides were determined in DBS samples collected from 19 healthy volunteers before and at four time points up to 2.5 h after consuming each of five typical breakfast meals varying in nutritional composition. Results At 2 h, glucose was within normal postprandial values (<140 mg/dl) for all meals; significantly lower glucose was seen after meal 2 (the lowest carbohydrate content) compared to the other meals. Insulin returned to normal fasting levels (<15 μIU/ml) in significantly more subjects (90%) after meal 2 and significantly fewer subjects (31%) after meal 4 (highest carbohydrate content) than the other meals. Triglycerides were elevated to a similar extent in all subjects, with no significant differences between meals; levels were still rising at 2.5 h. Conclusions Subjects were able to collect blood spots with minimum disruption to their normal daily activities. Relative ease of collection, analyte stability in dried blood, and the close correlation with serum levels that we have previously demonstrated makes DBS a convenient and simple tool for assessing the individual impact of different diets on postprandial dysmetabolism. PMID:20307382

  8. Thermal Wave Imaging: Flying SPOT Camera.

    Science.gov (United States)

    Wang, Yiqian

    1993-01-01

    A novel "Flying Spot" infrared camera for nondestructive evaluation (NDE) and nondestructive characterization is presented. The camera scans the focal point of an unmodulated heating laser beam across the sample in a raster. The detector of the camera tracks the heating spot in the same raster, but with a time delay. The detector is thus looking at the "thermal wake" of the heating spot. The time delay between heating and detection is determined by the speed of the laser spot and the distance between it and the detector image. Since this time delay can be made arbitrarily small, the camera is capable of making thermal wave images of phenomena which occur on a very short time scale. In addition, because the heat source is a very small spot, the heat flow is fully three-dimensional. This makes the camera system sensitive to features, like tightly closed vertical cracks, which are invisible to imaging systems which employ full-field heating. A detailed theory which relates the temperature profile around the heating spot to the sample thermal properties is also described. The camera represents a potentially useful tool for measuring thermal diffusivities of materials by means of fitting the recorded temperature profiles to the theoretical curves with the diffusivity as a fitting parameter.

  9. Quantification of the 3α and 3β epimers of 25-hydroxyvitamin D3in dried blood spots by LC-MS/MS using artificial whole blood calibration and chemical derivatization.

    Science.gov (United States)

    Müller, Miriam J; Stokes, Caroline S; Volmer, Dietrich A

    2017-04-01

    While the biological function of the 3α epimer of 25-hydroxyvitamin D 3 (25(OH)D 3 ) remains unknown, its presence needs to be accurately captured and separated from the main 3β epimer, to avoid positive bias in vitamin D status analyses. Several recent LC-MS/MS assays for 25(OH)D 3 successfully separate the 3α and 3β epimers by chromatography. Unfortunately, none of the existing LC-MS/MS assays, which utilize dried blood spots (DBS) as sampling/storage vessels, is able to quantify the individual epimers. DBS are often used for analysis of infant blood, however, and these samples are particularly likely to contain significant levels of interfering 3α epimer. Furthermore, proper calibration of DBS samples is much more difficult to achieve than for liquid serum or plasma samples. We addressed this important issue by creating an artificial vitamin D-free whole blood for calibration and then quantified 3α- and 3β-25(OH)D 3 levels from DBS. After chemical derivatization, the vitamin D epimers were separated on a PFP column and concentrations determined by electrospray ionization LC-MS/MS on a triple quadrupole mass spectrometer. Calibration with artificial whole blood showed improved precision over standard addition (7.6 versus 31.5% RSD for 3β-25(OH)D 3 ). The limits of quantification for 3β-25(OH)D 3 and for 3α-25(OH)D 3 were 1.0 and 0.1ng/mL, respectively. Excellent intra/interday precisions between 2.1 and 2.2% CV (intra) and 4.4-5.3% CV (inter) were established for 3β-25(OH)D 3 and 3α-25(OH)D 3 . For 3β-25(OH)D 3 , only small concentration-independent bias and deviation of <3.3ng/mL were seen between serum LC-MS/MS and DBS-LC-MS/MS measurements; analyses of 3α-25(OH)D 3 showed deviations of <0.8ng/mL in all experiments. Copyright © 2016 Elsevier B.V. All rights reserved.

  10. Metodologia para parametrizar e avaliar a técnica da ''burn-zinc'' no processo de soldagem a ponto por resistência Methodology for parameterize and assessment of the burn-zinc technique in the resistance spot welding process

    Directory of Open Access Journals (Sweden)

    Vinicius Castanheira do Nascimento

    2010-03-01

    Full Text Available Para minimizar os efeitos prejudiciais do zinco na soldagem a ponto por resistência de chapas galvanizadas, utiliza-se uma técnica tradicionalmente denominada ''Burn-Zinc'' (queima do zinco. Porém, existem poucas informações e estudos disponíveis na literatura sobre quando e como utilizá-la. O presente estudo teve a finalidade de avaliar a técnica de ''burn-zinc'', procurando entender melhor o fenômeno. Para tal, foi criada uma metodologia para determinação dos parâmetros ideais para cada combinação de chapa. Uma avaliação desta metodologia foi feita com uma série de soldagens com variações sistemáticas da corrente e pressão em níveis compatíveis para se obter a queima do Zn. Visualização das soldagens através de filmagem em alta velocidade, com sincronização dos sinais elétricos, foi empregada para entender os resultados. Uma vez definidos os parâmetros, soldagens foram realizadas com ou sem a aplicação da técnica. Os procedimentos experimentais propostos mostraram ser eficientes para a verificação e parametrização da técnica ''burn-zinc''. Mas houve evidências que a utilização da técnica nem sempre vai ocasionar redução no tempo total de operação.For minimizing the detrimental effects of zinc during resistance spot welding of galvanized sheets, a technique denominated Burn-Zinc is usually employed. However, there is no much information and studies available in the current literature about when and how to use this technique. The present work had the objective of assessing and understanding better this technique. For that, a methodology for determination of ideal burn-zing parameters as a function of the sheets was proposed. The evaluation of this methodology was carried out by a series of weldments, by systematically varying current and pressure at compatible levels for zinc burning. High speed filming, synchronized with the electrical signals, was employing for visualizing and results analyses

  11. Deep Brain Stimulation of the Basolateral Amygdala: Targeting Technique and Electrodiagnostic Findings

    Directory of Open Access Journals (Sweden)

    Jean-Philippe Langevin

    2016-08-01

    Full Text Available The amygdala plays a critical role in emotion regulation. It could prove to be an effective neuromodulation target in the treatment of psychiatric conditions characterized by failure of extinction. We aim to describe our targeting technique, and intra-operative and post-operative electrodiagnostic findings associated with the placement of deep brain stimulation (DBS electrodes in the amygdala. We used a transfrontal approach to implant DBS electrodes in the basolateral nucleus of the amygdala (BLn of a patient suffering from severe post-traumatic stress disorder. We used microelectrode recording (MER and awake intra-operative neurostimulation to assist with the placement. Post-operatively, the patient underwent monthly surveillance electroencephalograms (EEG. MER predicted the trajectory of the electrode through the amygdala. The right BLn showed a higher spike frequency than the left BLn. Intra-operative neurostimulation of the BLn elicited pleasant memories. The monthly EEG showed the presence of more sleep patterns over time with DBS. BLn DBS electrodes can be placed using a transfrontal approach. MER can predict the trajectory of the electrode in the amygdala and it may reflect the BLn neuronal activity underlying post-traumatic stress disorder PTSD. The EEG findings may underscore the reduction in anxiety.

  12. Ultrasonic Evaluation of Weld Strength for Aluminum Ultrasonic Spot Welds

    Science.gov (United States)

    Ghaffari, Bita; Hetrick, Elizabeth T.; Mozurkewich, George; Reatherford, Larry V.

    2005-04-01

    The goal of this work is to determine the feasibility of using an ultrasonic, non-destructive technique for post-process evaluation of aluminum ultrasonic spot welds. A focused immersion transducer was utilized to obtain a C-scan of the weld interface, from which a weighted ultrasonic contact area was estimated. Weldments were subsequently tested destructively to determine the weld strength. The square root of the weld contact area displayed a relatively good correlation with weld strength, r2=0.85.

  13. The simulation of the electron beam spot control

    Directory of Open Access Journals (Sweden)

    Stelian Emilian Oltean

    2011-12-01

    Full Text Available Electron beams have many special properties which make them particularly well suited for use in materials processing, wherever conventional techniques failed or proved to be inefficient. The entire process has a lot of time varying parameters, so using a distributed control system for 3d position of the electron beam spot may improve the quality of the material processing. Matlab environment was used for model implementation and simulations of the control system which contains the focusing and deflecting components. Due the nature of the process and knowing the electron beam equipment we proposed for the simulations scenarios with a 3D virtual surface.

  14. Optical and surface analysis of DNA microarrays to assess printed spot heterogeneity

    Science.gov (United States)

    Nagaraja Rao, Archana

    heterogeneity observed with high-resolution imaging techniques confirmed with confocal microscopy produces equally heterogeneous target capture under normal assay conditions, showing how spot drying produces signal variability. These methods are the first to interrogate single printed array spots providing new support that microspot signal heterogeneity is not purely a result of target hybridization but is initially sourced during immobilization of probes with droplet printing techniques. This will guide new thinking on immobilized density influence on assay performance and how to approach assay endpoints, either kinetically or at equilibrium binding, by modifying spot molecular environments to reliably capture their signal.

  15. Microstructure characterization of Friction Stir Spot Welded TRIP steel

    DEFF Research Database (Denmark)

    Lomholt, Trine Colding; Adachi, Yoshitaka; Peterson, Jeremy

    2012-01-01

    Transformation Induced Plasticity (TRIP) steels have not yet been successfully joined by any welding technique. It is desirable to search for a suitable welding technique that opens up for full usability of TRIP steels. In this study, the potential of joining TRIP steel with Friction Stir Spot...... Welding (FSSW) is investigated. The aim of the study is to investigate whether acceptable welds can be produced, and additionally, to obtain an understanding of the microstructural changes during welding. The microstructure was investigated with a combination of microscopical techniques with the aim...... of identifying the transformations occurring during welding. Reflected light microscopy, scanning electron microscopy, and electron backscatter diffraction were among the methods applied for detailed investigations. The microstructure adjacent to the welds can generally be subdivided in two thermo...

  16. 1,3:2,4-Dibenzylidene-D-sorbitol (DBS) and its derivatives--efficient, versatile and industrially-relevant low-molecular-weight gelators with over 100 years of history and a bright future.

    Science.gov (United States)

    Okesola, Babatunde O; Vieira, Vânia M P; Cornwell, Daniel J; Whitelaw, Nicole K; Smith, David K

    2015-06-28

    Dibenzylidene-D-sorbitol (DBS) has been a well-known low-molecular-weight gelator of organic solvents for over 100 years. As such, it constitutes a very early example of a supramolecular gel--a research field which has recently developed into one of intense interest. The ability of DBS to self-assemble into sample-spanning networks in numerous solvents is predicated upon its 'butterfly-like' structure, whereby the benzylidene groups constitute the 'wings' and the sorbitol backbone the 'body'--the two parts representing the molecular recognition motifs underpinning its gelation mechanism, with the nature of solvent playing a key role in controlling the precise assembly mode. This gelator has found widespread applications in areas as diverse as personal care products and polymer nucleation/clarification, and has considerable potential in applications such as dental composites, energy technology and liquid crystalline materials. Some derivatives of DBS have also been reported which offer the potential to expand the scope and range of applications of this family of gelators and endow the nansocale network with additional functionality. This review aims to explain current trends in DBS research, and provide insight into how by combining a long history of application, with modern methods of derivatisation and analysis, the future for this family of gelators is bright, with an increasing number of high-tech applications, from environmental remediation to tissue engineering, being within reach.

  17. Possible recombinogenic effect of caprolactam in the mammalian spot test.

    Science.gov (United States)

    Fahrig, R

    1989-11-01

    Tests of caprolactam in the mouse spot test showed that treatment with this compound increased the frequency of color spots among animals treated in utero. The nature of these spots suggests that caprolactam may induce spots through the induction of mitotic recombination.

  18. 7 CFR 28.423 - Middling Spotted Color.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 2 2010-01-01 2010-01-01 false Middling Spotted Color. 28.423 Section 28.423... REGULATIONS COTTON CLASSING, TESTING, AND STANDARDS Standards Spotted Cotton § 28.423 Middling Spotted Color. Middling Spotted Color is color which is within the range represented by a set of samples in the custody of...

  19. Bending Properties of Fiber-Reinforced Composites Retainers Bonded with Spot-Composite Coverage

    Science.gov (United States)

    Gandini, Paola; Tessera, Paola; Lassila, Lippo

    2017-01-01

    Orthodontic and periodontal splints are prepared with round or flat metallic wires. As these devices cannot be used in patients with allergy to metals or with aesthetic demands, fiber-reinforced composite (FRC) retainers have been introduced. Stiffness of FRC materials could reduce physiologic tooth movement. In order to lower rigidity of conventional FRC retainers, a modified construction technique that provided a partial (spot) composite coverage of the fiber has been tested and compared with metallic splints and full-bonded FRCs. Flat (Bond-a-Braid, Reliance Orthodontic Products) and round (Penta-one 0155, Masel Orthodontics) stainless steel splints, conventional FRC splints, and experimental spot-bonded FRC retainers (Everstick Ortho, StickTech) were investigated. The strength to bend the retainers at 0.1 mm deflection and at maximum load was measured with a modified Frasaco model. No significant differences were reported among load values of stainless steel wires and experimental spot-bonded FRC retainers at 0.1 mm deflection. Higher strength values were recoded for conventional full-bonded FRCs. At maximum load no significant differences were reported between metallic splints (flat and round) and experimental spot-bonded FRCs, and no significant differences were reported between spot- and full-bonded FRC splints. These results encourage further tests in order to evaluate clinical applications of experimental spot-bonded FRC retainers. PMID:29130047

  20. Bending Properties of Fiber-Reinforced Composites Retainers Bonded with Spot-Composite Coverage.

    Science.gov (United States)

    Sfondrini, Maria Francesca; Gandini, Paola; Tessera, Paola; Vallittu, Pekka K; Lassila, Lippo; Scribante, Andrea

    2017-01-01

    Orthodontic and periodontal splints are prepared with round or flat metallic wires. As these devices cannot be used in patients with allergy to metals or with aesthetic demands, fiber-reinforced composite (FRC) retainers have been introduced. Stiffness of FRC materials could reduce physiologic tooth movement. In order to lower rigidity of conventional FRC retainers, a modified construction technique that provided a partial (spot) composite coverage of the fiber has been tested and compared with metallic splints and full-bonded FRCs. Flat (Bond-a-Braid, Reliance Orthodontic Products) and round (Penta-one 0155, Masel Orthodontics) stainless steel splints, conventional FRC splints, and experimental spot-bonded FRC retainers (Everstick Ortho, StickTech) were investigated. The strength to bend the retainers at 0.1 mm deflection and at maximum load was measured with a modified Frasaco model. No significant differences were reported among load values of stainless steel wires and experimental spot-bonded FRC retainers at 0.1 mm deflection. Higher strength values were recoded for conventional full-bonded FRCs. At maximum load no significant differences were reported between metallic splints (flat and round) and experimental spot-bonded FRCs, and no significant differences were reported between spot- and full-bonded FRC splints. These results encourage further tests in order to evaluate clinical applications of experimental spot-bonded FRC retainers.

  1. Bending Properties of Fiber-Reinforced Composites Retainers Bonded with Spot-Composite Coverage

    Directory of Open Access Journals (Sweden)

    Maria Francesca Sfondrini

    2017-01-01

    Full Text Available Orthodontic and periodontal splints are prepared with round or flat metallic wires. As these devices cannot be used in patients with allergy to metals or with aesthetic demands, fiber-reinforced composite (FRC retainers have been introduced. Stiffness of FRC materials could reduce physiologic tooth movement. In order to lower rigidity of conventional FRC retainers, a modified construction technique that provided a partial (spot composite coverage of the fiber has been tested and compared with metallic splints and full-bonded FRCs. Flat (Bond-a-Braid, Reliance Orthodontic Products and round (Penta-one 0155, Masel Orthodontics stainless steel splints, conventional FRC splints, and experimental spot-bonded FRC retainers (Everstick Ortho, StickTech were investigated. The strength to bend the retainers at 0.1 mm deflection and at maximum load was measured with a modified Frasaco model. No significant differences were reported among load values of stainless steel wires and experimental spot-bonded FRC retainers at 0.1 mm deflection. Higher strength values were recoded for conventional full-bonded FRCs. At maximum load no significant differences were reported between metallic splints (flat and round and experimental spot-bonded FRCs, and no significant differences were reported between spot- and full-bonded FRC splints. These results encourage further tests in order to evaluate clinical applications of experimental spot-bonded FRC retainers.

  2. Visualization of hot spot formation in energetic materials under periodic mechanical excitation using phosphor thermography

    Science.gov (United States)

    Casey, Alex; Fenoglio, Gabriel; Detrinidad, Humberto

    2017-06-01

    Under mechanical excitation, energy is known to localize within an energetic material resulting in `hot spot' formation. While many formation mechanisms have been proposed, additional insight to heat generation mechanisms, the effect of binder/crystal interfaces, and predication capabilities can be gained by quantifying the initiation and growth of the hot spots. Phosphor thermography is a well established temperature sensing technique wherein an object's temperature is obtained by collecting the temperature dependent luminescence of an optically excited phosphor. Herein, the phosphor thermography technique has been applied to Dow Corning Sylgard® 184/octahydro 1,3,5,7 tetranitro 1,3,5,7 tetrazocine (HMX) composite materials under mechanical excitation in order to visualize the evolution of the temperature field, and thus hot spot formation, within the binder. Funded by AFOSR. Supported by the Department of Defense (DoD) through the National Defense Science & Engineering Graduate Fellowship (NDSEG) Program.

  3. Tests of fixity of the Indo-Atlantic hot spots relative to Pacific hot spots

    Science.gov (United States)

    Koivisto, Emilia A.; Andrews, David L.; Gordon, Richard G.

    2014-01-01

    Rates of inter-hot spot motion have been debated for decades. Herein we present updated predictions for the tracks of the Tristan da Cunha, Réunion, and Iceland hot spots assuming them to be fixed relative to Pacific hot spots. Uncertainties in Pacific hot spot rotations, which include uncertainties in the current locations of hot spots of 100-200 km, are combined with uncertainties in relative plate motions accumulated through the plate circuit to obtain the final uncertainty in the predicted positions (including uncertainties of 150-200 km in the current locations of the Indo-Atlantic hot spots). Improvements to reconstruction methods, to relative plate reconstructions, to age dates along the tracks, and to the geomagnetic reversal timescale lead to significant changes from prior results. When compared with the observed tracks, the predicted tracks indicate nominal rates of motion of only 2-6 mm a-1 of these Indo-Atlantic hot spots relative to Pacific hot spots over the past 48 Ma. Within the uncertainties, the rates range from no motion to rates as high as 8-13 mm a-1. For reconstructions prior to 48 Ma B.P., however, the apparent rates of inter-hot spot motion are much larger, 46-55 ± 20 mm a-1, if the motion occurred entirely between 68 Ma B.P. and 48 Ma B.P. Either hot spots moved rapidly before 48 Ma B.P., and slowed drastically at ≈ 48 Ma B.P., or global plate circuits through Antarctica become less reliable as one goes increasingly further into the past. Most paleomagnetic data favor the latter explanation.

  4. Interferometry to Image Surface Spots

    Science.gov (United States)

    Perrin, Guy

    2016-04-01

    I present in this lecture the technique of interferometric imaging at optical/infrared wavelengths. The technique has matured since the pioneering work of Michelson at the end of the XIXth—beginning of the XXth when he first resolved the surface of a star, Betelgeuse, with his colleague Pease. Images were obtained for the first time 20 years ago with the COAST instrument and interferometers have made constant progress to reach the minimum level where blind image reconstruction can be achieved. I briefly introduce the topic to recall why studying the surface and close environment of stars is important in some fields of stellar physics. I introduce the theory of imaging with telescopes and interferometers. I discuss the nature of interferometric data in this wavelength domain and give a few insights on the importance of getting access to visibility phases to obtain information on asymmetries of stellar surfaces. I then present the issue of aperture synthesis with a small number of telescopes, a signature of optical/infrared interferometers compared to the radio domain. Despite the impossibility to measure the phase of visibilities because of turbulence I show that useful information can be recovered from the closure phase. I eventually introduce the principles of image reconstruction and I discuss some recent results on several types of stars.

  5. Spot-Scanning Proton Arc (SPArc) Therapy: The First Robust and Delivery-Efficient Spot-Scanning Proton Arc Therapy

    Energy Technology Data Exchange (ETDEWEB)

    Ding, Xuanfeng, E-mail: Xuanfeng.ding@beaumont.org; Li, Xiaoqiang; Zhang, J. Michele; Kabolizadeh, Peyman; Stevens, Craig; Yan, Di

    2016-12-01

    Purpose: To present a novel robust and delivery-efficient spot-scanning proton arc (SPArc) therapy technique. Methods and Materials: A SPArc optimization algorithm was developed that integrates control point resampling, energy layer redistribution, energy layer filtration, and energy layer resampling. The feasibility of such a technique was evaluated using sample patients: 1 patient with locally advanced head and neck oropharyngeal cancer with bilateral lymph node coverage, and 1 with a nonmobile lung cancer. Plan quality, robustness, and total estimated delivery time were compared with the robust optimized multifield step-and-shoot arc plan without SPArc optimization (Arc{sub multi-field}) and the standard robust optimized intensity modulated proton therapy (IMPT) plan. Dose-volume histograms of target and organs at risk were analyzed, taking into account the setup and range uncertainties. Total delivery time was calculated on the basis of a 360° gantry room with 1 revolutions per minute gantry rotation speed, 2-millisecond spot switching time, 1-nA beam current, 0.01 minimum spot monitor unit, and energy layer switching time of 0.5 to 4 seconds. Results: The SPArc plan showed potential dosimetric advantages for both clinical sample cases. Compared with IMPT, SPArc delivered 8% and 14% less integral dose for oropharyngeal and lung cancer cases, respectively. Furthermore, evaluating the lung cancer plan compared with IMPT, it was evident that the maximum skin dose, the mean lung dose, and the maximum dose to ribs were reduced by 60%, 15%, and 35%, respectively, whereas the conformity index was improved from 7.6 (IMPT) to 4.0 (SPArc). The total treatment delivery time for lung and oropharyngeal cancer patients was reduced by 55% to 60% and 56% to 67%, respectively, when compared with Arc{sub multi-field} plans. Conclusion: The SPArc plan is the first robust and delivery-efficient proton spot-scanning arc therapy technique, which could potentially be implemented

  6. Intense equatorial flux spots on the surface of Earth's core

    Science.gov (United States)

    Jackson, A.

    2003-04-01

    A vast number of vector measurements of the Earth's magnetic field have recently become available from the satellite Oersted, currently in orbit monitoring the core magnetic field. In this presentation I will present new maps of the Earth's magnetic field at the surface of the fluid core derived from these satellite data which show intense flux spots in equatorial regions; the images are derived using a maximum entropy technique which is capable of reconstructing images with high dynamic range more precisely than conventional techniques. The intensity of these features is unusually large - they are comparable to high-latitude flux patches near the poles, previously identified as the major component of the dynamo field. A comparison with sunspots is tempting, though they are probably not associated with expulsion of toroidal magnetic field as is the case for the sun. Indeed, the tendency for pairing of these spots to the north and south of the geographical equator suggests they might be associated with the tops of so-called `Taylor columns' (indicative of the dominance of the rotation of the Earth) which have previously been suggested to be associated with the four high-latitude flux patches near the poles. Equatorially-trapped waves are known to exist in theory, and a correct interpretation of these features might lead to constraints on the strength of the hidden toroidal magnetic field within the Earth, as well as constraints on other physical regimes.

  7. Spotting Stellar Activity Cycles in Gaia Astrometry

    Science.gov (United States)

    Morris, Brett M.; Agol, Eric; Davenport, James R. A.; Hawley, Suzanne L.

    2018-03-01

    Astrometry from Gaia will measure the positions of stellar photometric centroids to unprecedented precision. We show that the precision of Gaia astrometry is sufficient to detect starspot-induced centroid jitter for nearby stars in the Tycho-Gaia Astrometric Solution (TGAS) sample with magnetic activity similar to the young G-star KIC 7174505 or the active M4 dwarf GJ 1243, but is insufficient to measure centroid jitter for stars with Sun-like spot distributions. We simulate Gaia observations of stars with 10 year activity cycles to search for evidence of activity cycles, and find that Gaia astrometry alone likely can not detect activity cycles for stars in the TGAS sample, even if they have spot distributions like KIC 7174505. We review the activity of the nearby low-mass stars in the TGAS sample for which we anticipate significant detections of spot-induced jitter.

  8. Sweet Spot Supersymmetry and Composite Messengers

    International Nuclear Information System (INIS)

    Ibe, Masahiro; Kitano, Ryuichiro

    2007-01-01

    Sweet spot supersymmetry is a phenomenologically and cosmologically perfect framework to realize a supersymmetric world at short distance. We discuss a class of dynamical models of supersymmetry breaking and its mediation whose low-energy effective description falls into this framework. Hadron fields in the dynamical models play a role of the messengers of the supersymmetry breaking. As is always true in the models of the sweet spot supersymmetry, the messenger scale is predicted to be 10 5 GeV ∼ mess ∼ 10 GeV. Various values of the effective number of messenger fields N mess are possible depending on the choice of the gauge group

  9. Volume dips; spot price ranges narrow

    International Nuclear Information System (INIS)

    Anon.

    1994-01-01

    This article is the September 1994 uranium market summary. Volume in the spot concentrates market fell below 1 million lbs U3O8. In total, twelve deals took place compared to 28 deals in August. Of the twelve deals, three took place in the spot concentrates market, two took place in the medium and long-term market, three in the conversion market, and four in the enrichment market. Restricted prices weakened, but unrestricted prices firmed slightly. The enrichment price range narrowed a bit

  10. Fast Keyword Spotting in Telephone Speech

    Directory of Open Access Journals (Sweden)

    J. Nouza

    2009-12-01

    Full Text Available In the paper, we present a system designed for detecting keywords in telephone speech. We focus not only on achieving high accuracy but also on very short processing time. The keyword spotting system can run in three modes: a an off-line mode requiring less than 0.1xRT, b an on-line mode with minimum (2 s latency, and c a repeated spotting mode, in which pre-computed values allow for additional acceleration. Its performance is evaluated on recordings of Czech spontaneous telephone speech using rather large and complex keyword lists.

  11. An online real time ultrasonic NDT system for the quality control of spot welding in the automotive industry

    International Nuclear Information System (INIS)

    Athi, N; Wylie, S R; Cullen, J D; Al-Jader, M; Al-Shamma'a, A I; Shaw, A

    2009-01-01

    Resistance spot welding is the main joining technique used for the fabrication of body-in-white structures in the automotive industry. The quality of the welds depends on the profile of the spot welding electrode cap. The increased use of zinc coated steel in the industry increases wear rate of the caps, making quality control more difficult. This paper presents a novel online real time ultrasonic NDE system for resistance spot welding which evaluates every weld as it is formed. SEM results are presented to show the alloying of the electrode caps.

  12. NOVEL ASPECTS OF SPOTTED WING DROSOPHILA BIOLOGY AND IMPROVED METHODS OF REARING

    Science.gov (United States)

    Drosophila suzukii (Mats.) or the spotted wing Drosophila (SWD), is a global pest of soft fruits that can now be reared on a standard Drosophila diet containing the fly's own natural food: soft-skinned berries. The techniques tested here can thwart bacterial and fungal disease that can destroy more ...

  13. Preliminary evaluation of sweet spot size in virtual sound reproduction using dipoles

    DEFF Research Database (Denmark)

    Lacouture Parodi, Yesenia; Rubak, Per

    2009-01-01

    to the loudspeakers. In this paper we present a follow up evaluation of the performance of the three inversion techniques when these conditions are violated. A setup to measure the sweet spot of different loudspeakers arrangements is described. Preliminary measurement results are presented for loudspeakers placed...

  14. Reduction of effective terahertz focal spot size by means of nested concentric parabolic reflectors

    NARCIS (Netherlands)

    Neumann, V.A.; Laurita, N.J.; Pan, LiDong; Armitage, N.P.

    2016-01-01

    An ongoing limitation of terahertz spectroscopy is that the technique is generally limited to the study of relatively large samples of order 4 mm across due to the generally large size of the focal beam spot. We present a nested concentric parabolic reflector design which can reduce the terahertz

  15. Application of Dried Blood Spots on Filter Paper for Detection of HIV ...

    African Journals Online (AJOL)

    Moreover the present technique of collecting blood for diagnosis is associated with increased risk of infection, loss and contamination of specimen. This study aimed at evaluating the use of blood spot dried on filter paper (under different storage conditions) for detection of HIV antibodies in patient\\'s serum as an alternative ...

  16. Identification of optimum friction stir spot welding process parameters controlling the properties of low carbon automotive steel joints

    Directory of Open Access Journals (Sweden)

    A.K. Lakshminarayanan

    2015-07-01

    Full Text Available Friction stir spot welding is a novel solid state process that has recently received considerable attention from various industries including automotive sectors due to many advantages over the resistance spot welding. However to apply this technique, the process parameters must be optimized to obtain improved mechanical properties compared to resistance spot welding. To achieve this, in this investigation, design of experiments was used to conduct the experiments for exploring the interdependence of the process parameters. A second order quadratic model for predicting the lap shear tensile strength of friction stir spot welded low carbon automotive steel joints was developed from the experimental obtained data. It is found that dwell time plays a major role in deciding the joint properties, which is followed by rotational speed and plunge depth. Further optimum process parameters were identified for maximum lap shear tensile strength using numerical and graphical optimization techniques.

  17. Comparative analysis of in-plane and out-of-plane mechanical behaviour of spot-welded and mechaincally fastened joints in thermoplastic composites

    NARCIS (Netherlands)

    Zhao, T.; Palardy, G.; Rans, C.D.; Benedictus, R.; Drechsler, K.

    2016-01-01

    Ultrasonic welding is a promising assembly technique for thermoplastic composites and it is well-suited for spot welding. In this paper, the in-plane and out-of-plane mechanical behaviour of ultrasonically spot-welded and mechanically fastened joints are investigated by double-lap shear and

  18. Transitional–turbulent spots and turbulent–turbulent spots in boundary layers

    Science.gov (United States)

    Wu, Xiaohua; Moin, Parviz; Wallace, James M.; Skarda, Jinhie; Lozano-Durán, Adrián; Hickey, Jean-Pierre

    2017-01-01

    Two observations drawn from a thoroughly validated direct numerical simulation of the canonical spatially developing, zero-pressure gradient, smooth, flat-plate boundary layer are presented here. The first is that, for bypass transition in the narrow sense defined herein, we found that the transitional–turbulent spot inception mechanism is analogous to the secondary instability of boundary-layer natural transition, namely a spanwise vortex filament becomes a Λ vortex and then, a hairpin packet. Long streak meandering does occur but usually when a streak is infected by a nearby existing transitional–turbulent spot. Streak waviness and breakdown are, therefore, not the mechanisms for the inception of transitional–turbulent spots found here. Rather, they only facilitate the growth and spreading of existing transitional–turbulent spots. The second observation is the discovery, in the inner layer of the developed turbulent boundary layer, of what we call turbulent–turbulent spots. These turbulent–turbulent spots are dense concentrations of small-scale vortices with high swirling strength originating from hairpin packets. Although structurally quite similar to the transitional–turbulent spots, these turbulent–turbulent spots are generated locally in the fully turbulent environment, and they are persistent with a systematic variation of detection threshold level. They exert indentation, segmentation, and termination on the viscous sublayer streaks, and they coincide with local concentrations of high levels of Reynolds shear stress, enstrophy, and temperature fluctuations. The sublayer streaks seem to be passive and are often simply the rims of the indentation pockets arising from the turbulent–turbulent spots. PMID:28630304

  19. Transitional-turbulent spots and turbulent-turbulent spots in boundary layers.

    Science.gov (United States)

    Wu, Xiaohua; Moin, Parviz; Wallace, James M; Skarda, Jinhie; Lozano-Durán, Adrián; Hickey, Jean-Pierre

    2017-07-03

    Two observations drawn from a thoroughly validated direct numerical simulation of the canonical spatially developing, zero-pressure gradient, smooth, flat-plate boundary layer are presented here. The first is that, for bypass transition in the narrow sense defined herein, we found that the transitional-turbulent spot inception mechanism is analogous to the secondary instability of boundary-layer natural transition, namely a spanwise vortex filament becomes a [Formula: see text] vortex and then, a hairpin packet. Long streak meandering does occur but usually when a streak is infected by a nearby existing transitional-turbulent spot. Streak waviness and breakdown are, therefore, not the mechanisms for the inception of transitional-turbulent spots found here. Rather, they only facilitate the growth and spreading of existing transitional-turbulent spots. The second observation is the discovery, in the inner layer of the developed turbulent boundary layer, of what we call turbulent-turbulent spots. These turbulent-turbulent spots are dense concentrations of small-scale vortices with high swirling strength originating from hairpin packets. Although structurally quite similar to the transitional-turbulent spots, these turbulent-turbulent spots are generated locally in the fully turbulent environment, and they are persistent with a systematic variation of detection threshold level. They exert indentation, segmentation, and termination on the viscous sublayer streaks, and they coincide with local concentrations of high levels of Reynolds shear stress, enstrophy, and temperature fluctuations. The sublayer streaks seem to be passive and are often simply the rims of the indentation pockets arising from the turbulent-turbulent spots.

  20. Transitional-turbulent spots and turbulent-turbulent spots in boundary layers

    Science.gov (United States)

    Wu, Xiaohua; Moin, Parviz; Wallace, James M.; Skarda, Jinhie; Lozano-Durán, Adrián; Hickey, Jean-Pierre

    2017-07-01

    Two observations drawn from a thoroughly validated direct numerical simulation of the canonical spatially developing, zero-pressure gradient, smooth, flat-plate boundary layer are presented here. The first is that, for bypass transition in the narrow sense defined herein, we found that the transitional-turbulent spot inception mechanism is analogous to the secondary instability of boundary-layer natural transition, namely a spanwise vortex filament becomes a ΛΛ vortex and then, a hairpin packet. Long streak meandering does occur but usually when a streak is infected by a nearby existing transitional-turbulent spot. Streak waviness and breakdown are, therefore, not the mechanisms for the inception of transitional-turbulent spots found here. Rather, they only facilitate the growth and spreading of existing transitional-turbulent spots. The second observation is the discovery, in the inner layer of the developed turbulent boundary layer, of what we call turbulent-turbulent spots. These turbulent-turbulent spots are dense concentrations of small-scale vortices with high swirling strength originating from hairpin packets. Although structurally quite similar to the transitional-turbulent spots, these turbulent-turbulent spots are generated locally in the fully turbulent environment, and they are persistent with a systematic variation of detection threshold level. They exert indentation, segmentation, and termination on the viscous sublayer streaks, and they coincide with local concentrations of high levels of Reynolds shear stress, enstrophy, and temperature fluctuations. The sublayer streaks seem to be passive and are often simply the rims of the indentation pockets arising from the turbulent-turbulent spots.

  1. Dual focal-spot imaging for phase extraction in phase-contrast radiography

    International Nuclear Information System (INIS)

    Donnelly, Edwin F.; Price, Ronald R.; Pickens, David R.

    2003-01-01

    The purpose of this study was to evaluate dual focal spot imaging as a method for extracting the phase component from a phase-contrast radiography image. All measurements were performed using a microfocus tungsten-target x-ray tube with an adjustable focal-spot size (0.01 mm to 0.045 mm). For each object, high-resolution digital radiographs were obtained with two different focal spot sizes to produce matched image pairs in which all other geometric variables as well as total exposure and tube kVp were held constant. For each image pair, a phase extraction was performed using pixel-wise division. The phase-extracted image resulted in an image similar to the standard image processing tool commonly referred to as 'unsharp masking' but with the additional edge-enhancement produced by phase-contrast effects. The phase-extracted image illustrates the differences between the two images whose imaging parameters differ only in focal spot size. The resulting image shows effects from both phase contrast as well as geometric unsharpness. In weakly attenuating materials the phase-contrast effect predominates, while in strongly attenuating materials the phase effects are so small that they are not detectable. The phase-extracted image in the strongly attenuating object reflects differences in geometric unsharpness. The degree of phase extraction depends strongly on the size of the smallest focal spot used. This technique of dual-focal spot phase-contrast radiography provides a simple technique for phase-component (edge) extraction in phase-contrast radiography. In strongly attenuating materials the phase-component is overwhelmed by differences in geometric unsharpness. In these cases the technique provides a form of unsharp masking which also accentuates the edges. Thus, the two effects are complimentary and may be useful in the detection of small objects

  2. A new technique for measurement of carrier thallium

    International Nuclear Information System (INIS)

    Study, K.T.

    1982-01-01

    Manufacturers of thallium-201 use the Rhodamine-B spot test for detection of ''carrier'' or elemental thallium. A more exacting and simpler quantitative technique for measuring carrier thallium is described and this spectrophotofluorometric technique takes advantage of thallium's fluorescence

  3. MICROARRAY IMAGE GRIDDING USING GRID LINE REFINEMENT TECHNIQUE

    Directory of Open Access Journals (Sweden)

    V.G. Biju

    2015-05-01

    Full Text Available An important stage in microarray image analysis is gridding. Microarray image gridding is done to locate sub arrays in a microarray image and find co-ordinates of spots within each sub array. For accurate identification of spots, most of the proposed gridding methods require human intervention. In this paper a fully automatic gridding method which enhances spot intensity in the preprocessing step as per a histogram based threshold method is used. The gridding step finds co-ordinates of spots from horizontal and vertical profile of the image. To correct errors due to the grid line placement, a grid line refinement technique is proposed. The algorithm is applied on different image databases and results are compared based on spot detection accuracy and time. An average spot detection accuracy of 95.06% depicts the proposed method’s flexibility and accuracy in finding the spot co-ordinates for different database images.

  4. Triggered tremor sweet spots in Alaska

    Science.gov (United States)

    Gomberg, Joan; Prejean, Stephanie

    2013-01-01

    To better understand what controls fault slip along plate boundaries, we have exploited the abundance of seismic and geodetic data available from the richly varied tectonic environments composing Alaska. A search for tremor triggered by 11 large earthquakes throughout all of seismically monitored Alaska reveals two tremor “sweet spots”—regions where large-amplitude seismic waves repeatedly triggered tremor between 2006 and 2012. The two sweet spots locate in very different tectonic environments—one just trenchward and between the Aleutian islands of Unalaska and Akutan and the other in central mainland Alaska. The Unalaska/Akutan spot corroborates previous evidence that the region is ripe for tremor, perhaps because it is located where plate-interface frictional properties transition between stick-slip and stably sliding in both the dip direction and laterally. The mainland sweet spot coincides with a region of complex and uncertain plate interactions, and where no slow slip events or major crustal faults have been noted previously. Analyses showed that larger triggering wave amplitudes, and perhaps lower frequencies (sweet spots also does not occur during slow slip events visually detectable in GPS data, although slow slip below the detection threshold may have facilitated tremor triggering.

  5. Hot-spot tectonics on Io

    Science.gov (United States)

    Mcewen, A. S.

    1985-01-01

    The thesis is that extensional tectonics and low-angle detachment faults probably occur on Io in association with the hot spots. These processes may occur on a much shorter timescale on Ion than on Earth, so that Io could be a natural laboratory for the study of thermotectonics. Furthermore, studies of heat and detachment in crustal extension on Earth and the other terresrial planets (especially Venus and Mars) may provide analogs to processes on Io. The geology of Io is dominated by volcanism and hot spots, most likely the result of tidal heating. Hot spots cover 1 to 2% of Io's surface, radiating at temperatures typically from 200 to 400 K, and occasionally up to 700K. Heat loss from the largest hot spots on Io, such as Loki Patera, is about 300 times the heat loss from Yellowstone, so a tremendous quantity of energy is available for volcanic and tectonic work. Active volcanism on Io results in a resurfacing rate as high as 10 cm per year, yet many structural features are apparent on the surface. Therefore, the tectonics must be highly active.

  6. Dramatic Change in Jupiter's Great Red Spot

    Science.gov (United States)

    Simon, A. A.; Wong, M. H.; Rogers, J. H.; Orton, G. S.; de Pater, I.; Asay-Davis, X.; Carlson, R. W.; Marcus, P. S.

    2015-01-01

    Jupiter's Great Red Spot (GRS) is one of its most distinct and enduring features, having been continuously observed since the 1800's. It currently spans the smallest latitude and longitude size ever recorded. Here we show analyses of 2014 Hubble spectral imaging data to study the color, structure and internal dynamics of this long-live storm.

  7. Analysing the strength of friction stir spot welded joints of aluminium alloy by fuzzy logic

    Science.gov (United States)

    Vaira Vignesh, R.; Padmanaban, R.; Arivarasu, M.; Karthick, K. P.; Abirama Sundar, A.; Gokulachandran, J.

    2016-09-01

    Friction stir spot welding (FSSW) is a recent joining technique developed for spot welding of thin metal sheets. This process currently finds application in automotive, aerospace, marine and sheet metal industry. In this work, the effect of FSSW process parameters namely tool rotation speed, shoulder diameter and dwell time on Tensile shear failure load (TSFL) is investigated. Box-Behnken design is selected for conducting experiments. Fuzzy based soft computing is used to develop a model for TSFL of AA6061 joints fabricated by FSSW. The interaction of the process parameters on TSFL is also presented.

  8. Does early verbal fluency decline after STN implantation predict long-term cognitive outcome after STN-DBS in Parkinson's disease?

    Science.gov (United States)

    Borden, Alaina; Wallon, David; Lefaucheur, Romain; Derrey, Stéphane; Fetter, Damien; Verin, Marc; Maltête, David

    2014-11-15

    An early and transient verbal fluency (VF) decline and impairment in frontal executive function, suggesting a cognitive microlesion effect may influence the cognitive repercussions related to subthalamic nucleus deep brain stimulation (STN-DBS). Neuropsychological tests including semantic and phonemic verbal fluency were administered both before surgery (baseline), the third day after surgery (T3), at six months (T180), and at an endpoint multiple years after surgery (Tyears). Twenty-four patients (mean age, 63.5 ± 9.5 years; mean disease duration, 12 ± 5.8 years) were included. Both semantic and phonemic VF decreased significantly in the acute post-operative period (44.4 ± 28.2% and 34.3 ± 33.4%, respectively) and remained low at 6 months compared to pre-operative levels (decrease of 3.4 ± 47.8% and 10.8 ± 32.1%) (P < 0.05). Regression analysis showed phonemic VF to be an independent factor of decreased phonemic VF at six months. Age was the only independent predictive factor for incident Parkinson's disease dementia (PDD) (F (4,19)=3.4, P<0.03). An acute post-operative decline in phonemic VF can be predictive of a long-term phonemic VF deficit. The severity of this cognitive lesion effect does not predict the development of dementia which appears to be disease-related. Copyright © 2014 Elsevier B.V. All rights reserved.

  9. Nondestructive Testing of Ceramic Hip Joint Implants with Laser Spot Thermography

    Directory of Open Access Journals (Sweden)

    Roemer J.

    2017-12-01

    Full Text Available The paper presents an application of laser spot thermography for damage detection in ceramic samples with surface breaking cracks. The measurement technique is an active thermographic approach based on an external heat delivery to a test sample, by means of a laser pulse, and signal acquisition by an infrared camera. Damage detection is based on the analysis of surface temperature distribution near the exciting laser spot. The technique is nondestructive, non-contact and allows for full-field measurements. Surface breaking cracks are a very common type of damage in ceramic materials that are introduced in the manufacturing process or during the service period. This paper briefly discusses theoretical background of laser spot thermography, describes the experimental test rig and signal processing methods involved. Damage detection results obtained with laser spot thermography are compared with reference measurements obtained with vibrothermography. This is a different modality of active thermography, that has been previously proven effective for this type of damage. We demonstrate that both measurement techniques can be effectively used for damage detection and quality control applications of ceramic materials.

  10. Characterization of Microstructure and Mechanical Properties of Resistance Spot Welded DP600 Steel

    Directory of Open Access Journals (Sweden)

    Ali Ramazani

    2015-09-01

    Full Text Available Resistance spot welding (RSW as a predominant welding technique used for joining steels in automotive applications needs to be studied carefully in order to improve the mechanical properties of the spot welds. The objectives of the present work are to characterize the resistance spot weldment of DP600 sheet steels. The mechanical properties of the welded joints were evaluated using tensile-shear and cross-tensile tests. The time-temperature evolution during the welding cycle was measured. The microstructures observed in different sites of the welds were correlated to thermal history recorded by thermocouples in the corresponding areas. It was found that cracks initiated in the periphery region of weld nuggets with a martensitic microstructure and a pull-out failure mode was observed. It was also concluded that tempering during RSW was the main reason for hardness decrease in HAZ.

  11. The Mechanical Behavior of Friction-Stir Spot Welded Aluminum Alloys

    Science.gov (United States)

    Güler, Hande

    2014-10-01

    Aluminum and alloys are widely used in the automotive industry due to the light weight, good formability, and malleability. Spot welding is the most commonly used joining method of these materials, but the high current requirements and the inconsistent quality of the final welds make this process unsuitable. An alternative welding technique, the friction-stir spot welding process, can also be successfully used in joining of aluminum and alloys. In this study, 1-mm-thick AA5754 Al-alloy plates in the H-111 temper conditions were joined by friction-stir spot welding using two different weld parameters such as tool rotational speed and dwell time. Mechanical properties of the joints were obtained with extensive hardness measurements and tensile shear tests. The effect of these parameters on the failure modes of welded joints was also determined.

  12. Submicron hollow spot generation by solid immersion lens and structured illumination

    International Nuclear Information System (INIS)

    Kim, M-S; Scharf, T; Herzig, H P; Assafrao, A C; Wachters, A J H; Pereira, S F; Urbach, H P; Brun, M; Olivier, S; Nicoletti, S

    2012-01-01

    We report on the experimental and numerical demonstration of immersed submicron-size hollow focused spots, generated by structuring the polarization state of an incident light beam impinging on a micro-size solid immersion lens (μ-SIL) made of SiO 2 . Such structured focal spots are characterized by a doughnut-shaped intensity distribution, whose central dark region is of great interest for optical trapping of nano-size particles, super-resolution microscopy and lithography. In this work, we have used a high-resolution interference microscopy technique to measure the structured immersed focal spots, whose dimensions were found to be significantly reduced due to the immersion effect of the μ-SIL. In particular, a reduction of 37% of the dark central region was verified. The measurements were compared with a rigorous finite element method model for the μ-SIL, revealing excellent agreement between them. (paper)

  13. Real-time spot size camera for pulsed high-energy radiographic machines

    International Nuclear Information System (INIS)

    Watson, S.A.

    1993-01-01

    The focal spot size of an x-ray source is a critical parameter which degrades resolution in a flash radiograph. For best results, a small round focal spot is required. Therefore, a fast and accurate measurement of the spot size is highly desirable to facilitate machine tuning. This paper describes two systems developed for Los Alamos National Laboratory's Pulsed High-Energy Radiographic Machine Emitting X-rays (PHERMEX) facility. The first uses a CCD camera combined with high-brightness floors, while the second utilizes phosphor storage screens. Other techniques typically record only the line spread function on radiographic film, while systems in this paper measure the more general two-dimensional point-spread function and associated modulation transfer function in real time for shot-to-shot comparison

  14. Dried blood spots: liquid chromatography-mass spectrometry analysis of Δ9-tetrahydrocannabinol and its main metabolites.

    Science.gov (United States)

    Mercolini, Laura; Mandrioli, Roberto; Sorella, Vittorio; Somaini, Lorenzo; Giocondi, Daniele; Serpelloni, Giovanni; Raggi, Maria Augusta

    2013-01-04

    A sensitive and selective HPLC-MS/MS method has been developed for the first time for the analysis of Δ(9)-tetrahydrocannabinol (the most important active cannabinoid) and its hydroxylated and carboxylated metabolites in human Dried Blood Spots (DBSs). The simultaneous determination of Δ(9)-tetrahydrocannabinol and its two main metabolites allows assessing the time elapsed after the drug intake and distinguishing between acute or former consumption. This is an important information in specific contexts such as "on street" controls by police forces. DBSs have been chosen as the optimal biological matrix for this kind of testing, since they provide information on the actual state of intoxication, without storage and transportation problems usually associated with classical blood testing. The analysis is carried out on a C8 reversed phase column with a mobile phase composed of 0.1% formic acid in a water/methanol mixture and an electrospray ionisation (ESI) source, coupled to a triple quadrupole mass spectrometer. The method was validated according to international guidelines, with satisfactory results in terms of extraction yields, precision, stability and accuracy. Application to real DBS samples from Cannabis abusers gave reliable results, thus confirming the methodology suitability for roadside testing. Copyright © 2012 Elsevier B.V. All rights reserved.

  15. Depth Of Modulation And Spot Size Selection In Bar-Code Laser Scanners

    Science.gov (United States)

    Barkan, Eric; Swartz, Jerome

    1982-04-01

    Many optical and electronic considerations enter into the selection of optical spot size in flying spot laser scanners of the type used in modern industrial and commerical environments. These include: the scale of the symbols to be read, optical background noise present in the symbol substrate, and factors relating to the characteristics of the signal processor. Many 'front ends' consist of a linear signal conditioner followed by nonlinear conditioning and digitizing circuitry. Although the nonlinear portions of the circuit can be difficult to characterize mathematically, it is frequently possible to at least give a minimum depth of modulation measure to yield a worst-case guarantee of adequate performance with respect to digitization accuracy. Depth of modulation actually delivered to the nonlinear circuitry will depend on scale, contrast, and noise content of the scanned symbol, as well as the characteristics of the linear conditioning circuitry (eg. transfer function and electronic noise). Time and frequency domain techniques are applied in order to estimate the effects of these factors in selecting a spot size for a given system environment. Results obtained include estimates of the effects of the linear front end transfer function on effective spot size and asymmetries which can affect digitization accuracy. Plots of convolution-computed modulation patterns and other important system properties are presented. Considerations are limited primarily to Gaussian spot profiles but also apply to more general cases. Attention is paid to realistic symbol models and to implications with respect to printing tolerances.

  16. Multiresolution Source/Filter Model for Low Bitrate Coding of Spot Microphone Signals

    Directory of Open Access Journals (Sweden)

    Panagiotis Tsakalides

    2008-04-01

    Full Text Available A multiresolution source/filter model for coding of audio source signals (spot recordings is proposed. Spot recordings are a subset of the multimicrophone recordings of a music performance, before the mixing process is applied for producing the final multichannel audio mix. The technique enables low bitrate coding of spot signals with good audio quality (above 3.0 perceptual grade compared to the original. It is demonstrated that this particular model separates the various microphone recordings of a multimicrophone recording into a part that mainly characterizes a specific microphone signal and a part that is common to all signals of the same recording (and can thus be omitted during transmission. Our interest in low bitrate coding of spot recordings is related to applications such as remote mixing and real-time collaboration of musicians who are geographically distributed. Using the proposed approach, it is shown that it is possible to encode a multimicrophone audio recording using a single audio channel only, with additional information for each spot microphone signal in the order of 5 kbps, for good-quality resynthesis. This is verified by employing both objective and subjective measures of performance.

  17. Multiresolution Source/Filter Model for Low Bitrate Coding of Spot Microphone Signals

    Directory of Open Access Journals (Sweden)

    Mouchtaris Athanasios

    2008-01-01

    Full Text Available A multiresolution source/filter model for coding of audio source signals (spot recordings is proposed. Spot recordings are a subset of the multimicrophone recordings of a music performance, before the mixing process is applied for producing the final multichannel audio mix. The technique enables low bitrate coding of spot signals with good audio quality (above 3.0 perceptual grade compared to the original. It is demonstrated that this particular model separates the various microphone recordings of a multimicrophone recording into a part that mainly characterizes a specific microphone signal and a part that is common to all signals of the same recording (and can thus be omitted during transmission. Our interest in low bitrate coding of spot recordings is related to applications such as remote mixing and real-time collaboration of musicians who are geographically distributed. Using the proposed approach, it is shown that it is possible to encode a multimicrophone audio recording using a single audio channel only, with additional information for each spot microphone signal in the order of 5 kbps, for good-quality resynthesis. This is verified by employing both objective and subjective measures of performance.

  18. EDF experience with {open_quotes}hot spot{close_quotes} management

    Energy Technology Data Exchange (ETDEWEB)

    Guio, J.M. de [Blayais Nuclear Power Plant, St. Ciers (France)

    1995-03-01

    During the past few years, {open_quotes}hot spots{close_quotes} due to the presence of particles of metal activated during their migration through the reactor core, have been detected at several French pressurized water reactor (PWR) units. These {open_quotes}hot spots,{close_quotes} which generate very high dose rates (from about 10 Gy/h to 200 G/h) are a significant factor in increase occupational exposures during outrates. Of particular concern are the difficult cases which prolong outage duration and increase the volume of radiological waste. Confronted with this situation, Electricite de France (EDF) has set up a national research group, as part of its ALARA program, to establish procedures and techniques to avoid, detect, and eliminate of hot spots. In particular, specific processes have been developed to eliminate these hot spots which are most costly in terms of occupational exposure due to the need for reactor maintenance. This paper sets out the general approach adopted at EDF so far to cope with the problem of hot spots, illustrated by experience at Blayais 3 and 4.

  19. Modeling of the fracture behavior of spot welds using advanced micro-mechanical damage models

    International Nuclear Information System (INIS)

    Sommer, Silke

    2010-01-01

    This paper presents the modeling of deformation and fracture behavior of resistance spot welded joints in DP600 steel sheets. Spot welding is still the most commonly used joining technique in automotive engineering. In overloading situations like crash joints are often the weakest link in a structure. For those reasons, crash simulations need reliable and applicable tools to predict the load bearing capacity of spot welded components. Two series of component tests with different spot weld diameters have shown that the diameter of the weld nugget is the main influencing factor affecting fracture mode (interfacial or pull-out fracture), load bearing capacity and energy absorption. In order to find a correlation between nugget diameter, load bearing capacity and fracture mode, the spot welds are simulated with detailed finite element models containing base metal, heat affected zone and weld metal in lap-shear loading conditions. The change in fracture mode from interfacial to pull-out or peel-out fracture with growing nugget diameter under lap-shear loading was successfully modeled using the Gologanu-Leblond model in combination with the fracture criteria of Thomason and Embury. A small nugget diameter is identified to be the main cause for interfacial fracture. In good agreement with experimental observations, the calculated pull-out fracture initiates in the base metal at the boundary to the heat affected zone.

  20. Modeling of the fracture behavior of spot welds using advanced micro-mechanical damage models

    Science.gov (United States)

    Sommer, Silke

    2010-06-01

    This paper presents the modeling of deformation and fracture behavior of resistance spot welded joints in DP600 steel sheets. Spot welding is still the most commonly used joining technique in automotive engineering. In overloading situations like crash joints are often the weakest link in a structure. For those reasons, crash simulations need reliable and applicable tools to predict the load bearing capacity of spot welded components. Two series of component tests with different spot weld diameters have shown that the diameter of the weld nugget is the main influencing factor affecting fracture mode (interfacial or pull-out fracture), load bearing capacity and energy absorption. In order to find a correlation between nugget diameter, load bearing capacity and fracture mode, the spot welds are simulated with detailed finite element models containing base metal, heat affected zone and weld metal in lap-shear loading conditions. The change in fracture mode from interfacial to pull-out or peel-out fracture with growing nugget diameter under lap-shear loading was successfully modeled using the Gologanu-Leblond model in combination with the fracture criteria of Thomason and Embury. A small nugget diameter is identified to be the main cause for interfacial fracture. In good agreement with experimental observations, the calculated pull-out fracture initiates in the base metal at the boundary to the heat affected zone.

  1. Plasma spot welding of ferritic stainless steels

    Directory of Open Access Journals (Sweden)

    Lešnjak, A.

    2002-06-01

    Full Text Available Plasma spot welding of ferritic stainless steels is studied. The study was focused on welding parameters, plasma and shielding gases and the optimum welding equipment. Plasma-spot welded overlap joints on a 0.8 mm thick ferritic stainless steel sheet were subjected to a visual examination and mechanical testing in terms of tension-shear strength. Several macro specimens were prepared. Plasma spot welding is suitable to use the same gas as shielding gas and as plasma gas, i.e., a 98 % Ar/2 % H 2 gas mixture. Tension-shear strength of plasma-spot welded joints was compared to that of resistance-spot welded joints. It was found that the resistance welded joints withstand a somewhat stronger load than the plasma welded joints due to a larger weld spot diameter of the former. Strength of both types of welded joints is approximately the same.

    El artículo describe el proceso de soldeo de aceros inoxidables ferríticos por puntos con plasma. La investigación se centró en el establecimiento de los parámetros óptimos de la soldadura, la definición del gas de plasma y de protección más adecuado, así como del equipo óptimo para la realización de la soldadura. Las uniones de láminas de aceros inoxidables ferríticos de 0,8 mm de espesor, soldadas a solape por puntos con plasma, se inspeccionaron visualmente y se ensayaron mecánicamente mediante el ensayo de cizalladura por tracción. Se realizaron macro pulidos. Los resultados de la investigación demostraron que la solución más adecuada para el soldeo por puntos con plasma es elegir el mismo gas de plasma que de protección. Es decir, una mezcla de 98 % de argón y 2 % de hidrógeno. La resistencia a la cizalladura por tracción de las uniones soldadas por puntos con plasma fue comparada con la resistencia de las uniones soldadas por resistencia por puntos. Se llegó a la conclusión de que las uniones soldadas por resistencia soportan una carga algo mayor que la uniones

  2. Turbulent Region Near Jupiter's Great Red Spot

    Science.gov (United States)

    1997-01-01

    True and false color mosaics of the turbulent region west of Jupiter's Great Red Spot. The Great Red Spot is on the planetary limb on the right hand side of each mosaic. The region west (left) of the Great Red Spot is characterized by large, turbulent structures that rapidly change in appearance. The turbulence results from the collision of a westward jet that is deflected northward by the Great Red Spot into a higher latitude eastward jet. The large eddies nearest to the Great Red Spot are bright, suggesting that convection and cloud formation are active there.The top mosaic combines the violet (410 nanometers) and near infrared continuum (756 nanometers) filter images to create a mosaic similar to how Jupiter would appear to human eyes. Differences in coloration are due to the composition and abundance of trace chemicals in Jupiter's atmosphere. The lower mosaic uses the Galileo imaging camera's three near-infrared (invisible) wavelengths (756 nanometers, 727 nanometers, and 889 nanometers displayed in red, green, and blue) to show variations in cloud height and thickness. Light blue clouds are high and thin, reddish clouds are deep, and white clouds are high and thick. Purple most likely represents a high haze overlying a clear deep atmosphere. Galileo is the first spacecraft to distinguish cloud layers on Jupiter.The mosaic is centered at 16.5 degrees south planetocentric latitude and 85 degrees west longitude. The north-south dimension of the Great Red Spot is approximately 11,000 kilometers. The smallest resolved features are tens of kilometers in size. North is at the top of the picture. The images used were taken on June 26, 1997 at a range of 1.2 million kilometers (1.05 million miles) by the Solid State Imaging (SSI) system on NASA's Galileo spacecraft.The Jet Propulsion Laboratory, Pasadena, CA manages the Galileo mission for NASA's Office of Space Science, Washington, DC. JPL is an operating division of California Institute of Technology (Caltech

  3. SPOT: How good for geology? A comparison with LANDSAT MSS

    Science.gov (United States)

    Sesoeren, A.

    1986-12-01

    Geological interpretation possibilities of SPOT MSS and LANDSAT MSS positive prints enlarged to the same scale were compared, using as a test area part of the Jebel Amour (Algeria). The SPOT imagery offers many advantages, filling the gap between remote sensing from space and aerial photography. The best results by visual interpretation are obtained in combining SPOT for the required details with LANDSAT for the synoptic veiw. Further improvements are expected from the use of SPOT stereo-pairs.

  4. Spotted-Leaf Mutants of Rice (Oryza sativa

    Directory of Open Access Journals (Sweden)

    Qi-na HUANG

    2010-12-01

    Full Text Available Many rice spotted-leaf (spl mutants are ideal sources for understanding the mechanisms involved in blast resistance, bacterial blight resistance and programmed cell death in plants. The genetic controls of 50 spotted-leaf mutants in rice have been characterized and a few spotted-leaf genes have been isolated as well. This article reviews the origin, genetic modes, isolation and characterization of spotted-leaf genes responsible for their phenotypes, and their resistance responses to main rice diseases.

  5. Disability in Activities of Daily Living and Severity of Dyskinesias Determine the Handicap of Parkinson's Disease Patients in Advanced Stage Selected to DBS.

    Science.gov (United States)

    Coelho, Miguel; Abreu, Daisy; Correia-Guedes, Leonor; Lobo, Patricia Pita; Fabbri, Margherita; Godinho, Catarina; Domingos, Josefa; Albuquerque, Luisa; Freitas, Vanda; Pereira, João Miguel; Cattoni, Begona; Carvalho, Herculano; Reimão, Sofia; Rosa, Mário M; Ferreira, António Gonalves; Ferreira, Joaquim J

    2017-01-01

    There is scarce data on the level of handicap in Parkinson's disease (PD) and none in advanced stage PD. To assess the handicap in advanced stage PD patients with disabling levodopa-induced motor complications selected to deep brain stimulation (DBS). Data was prospectively recorded during routine evaluation for DBS. Handicap was measured using London Handicap Scale (LHS) (0 = maximal handicap; 1 = no handicap). Disease severity was evaluated using the Hoehn & Yahr scale and the UPDRS/MDS-UPDRS, during off and on after a supra-maximal dose of levodopa. Schwab and England Scale (S&E) was scored in off and on. Dyskinesias were scored using the modified Abnormal Involuntary Movement Scale (mAIMS). Results concern cross-sectional assessment before DBS. 100 PD patients (mean age 61 (±7.6); mean disease duration 12.20 (±4.6) years) were included. Median score of motor MDS-UPDRS was 54 in off and 25 in on. Mean total LHS score was 0.56 (±0.14). Patients were handicapped in several domains with a wide range of severity. Physical Independence and Social Integration were the most affected domains. Determinants of total LHS score were MDS-UPDRS part II off (β= -0.271; p = 0.020), S&E on (β= 0.264; p = 0.005) and off (β= 0.226; p = 0.020), and mAIMS on (β= -0.183; p = 0.042) scores (R2  = 29.6%). We were able to use handicap to measure overall health condition in advanced stage PD. Patients were moderately to highly handicapped and this was strongly determined by disability in ADL and dyskinesias. Change in handicap may be a good patient-centred outcome to assess efficiency of DBS.

  6. 7 CFR 27.93 - Bona fide spot markets.

    Science.gov (United States)

    2010-01-01

    ... REGULATIONS COTTON CLASSIFICATION UNDER COTTON FUTURES LEGISLATION Regulations Spot Markets § 27.93 Bona fide spot markets. The following markets have been determined, after investigation, and are hereby... 7 Agriculture 2 2010-01-01 2010-01-01 false Bona fide spot markets. 27.93 Section 27.93...

  7. Sowing rates for reforestation by the seed-spotting method

    Science.gov (United States)

    Gilbert H. Schubert; Harry A. Fowells

    1964-01-01

    Presents guides to determine the number of seeds to sow per spot and the number of spots required per acre to obtain acceptable stocking. Based on theoretical probabilities, these guides were found to be reasonably close to actual field results When the probability-of-success was at least 55 percent. To compensate for lower actual stocking, increase the number of spots...

  8. 7 CFR 28.424 - Strict Low Middling Spotted Color.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 2 2010-01-01 2010-01-01 false Strict Low Middling Spotted Color. 28.424 Section 28.424 Agriculture Regulations of the Department of Agriculture AGRICULTURAL MARKETING SERVICE (Standards... Spotted Color. Strict Low Middling Spotted Color is color which is within the range represented by a set...

  9. 7 CFR 28.421 - Good Middling Spotted Color.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 2 2010-01-01 2010-01-01 false Good Middling Spotted Color. 28.421 Section 28.421 Agriculture Regulations of the Department of Agriculture AGRICULTURAL MARKETING SERVICE (Standards... Color. Good Middling Spotted Color is color which is better than Strict Middling Spotted Color. ...

  10. 7 CFR 28.426 - Strict Good Ordinary Spotted Color.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 2 2010-01-01 2010-01-01 false Strict Good Ordinary Spotted Color. 28.426 Section 28.426 Agriculture Regulations of the Department of Agriculture AGRICULTURAL MARKETING SERVICE (Standards... Spotted Color. Strict Good Ordinary Spotted Color is color which is within the range represented by a set...

  11. White Spot Syndrome Virus infection in Penaeus monodon is ...

    Indian Academy of Sciences (India)

    2013-11-06

    Nov 6, 2013 ... White Spot Syndrome Virus (WSSV) is a major pathogen in shrimp aquaculture, and its rampant spread has resulted in great economic loss. ... has been increasingly hampered by white spot syndrome disease caused by White Spot ..... metabolic proteins have additional roles in immunity and transcriptional ...

  12. Spot-Welding Gun With Pivoting Twin-Collet Assembly

    Science.gov (United States)

    Nguyen, Francis; Simpson, Gareth; Hoult, William S.

    1996-01-01

    Modified spot-welding gun includes pivoting twin-collet assembly that holds two spot-welding electrodes. Designed to weld highly conductive (30 percent gold) brazing-alloy foils to thin nickel alloy workpieces; also suitable for other spot-welding applications compatible with two-electrode configuration.

  13. Great red spot dependence on solar activity

    International Nuclear Information System (INIS)

    Schatten, K.H.

    1979-01-01

    A new inquiry has been made into the question of whether Jupiter's Great Red Spot shows a solar activity dependence. From 1892 to 1947 a clear correlation was present. A dearth of sightings in the seventeenth century, along with the Maunder Minimum, further supports the relation. An anticorrelation, however, from l948 to l967 removed support for such an effect. The old observations have reexamined and recent observations have also been studied. The author reexamines this difficult question and suggests a possible physical mechanism for a Sun-Jovian weather relation. Prinn and Lewis' conversion reaction of Phosphine gas to triclinic red phosphorous crystals is a reaction dependent upon solar radiation. It may explain the dependence found, as well as the striking appearance of the Great Red Spot in the UV

  14. Dynamically variable spot size laser system

    Science.gov (United States)

    Gradl, Paul R. (Inventor); Hurst, John F. (Inventor); Middleton, James R. (Inventor)

    2012-01-01

    A Dynamically Variable Spot Size (DVSS) laser system for bonding metal components includes an elongated housing containing a light entry aperture coupled to a laser beam transmission cable and a light exit aperture. A plurality of lenses contained within the housing focus a laser beam from the light entry aperture through the light exit aperture. The lenses may be dynamically adjusted to vary the spot size of the laser. A plurality of interoperable safety devices, including a manually depressible interlock switch, an internal proximity sensor, a remotely operated potentiometer, a remotely activated toggle and a power supply interlock, prevent activation of the laser and DVSS laser system if each safety device does not provide a closed circuit. The remotely operated potentiometer also provides continuous variability in laser energy output.

  15. Experimental and simulated strength of spot welds

    DEFF Research Database (Denmark)

    Nielsen, Chris Valentin; Bennedbæk, Rune A.K.; Larsen, Morten B.

    2014-01-01

    Weld strength testing of single spots in DP600 steel is presented for the three typical testing procedures, i.e. tensile-shear, cross-tension and peel testing. Spot welds are performed at two sets of welding parameters and strength testing under these conditions is presented by load......-elongation curves revealing the maximum load and the elongation at break. Welding and strength testing is simulated by SORPAS® 3D, which allows the two processes to be prepared in a combined simulation, such that the simulated welding properties are naturally applied to the simulation of strength testing. Besides...... the size and shape of the weld nugget, these properties include the new strength of the material in the weld and the heat affected zone based on the predicted hardness resulting from microstructural phase changes simulated during cooling of the weld before strength testing. Comparisons between overall...

  16. SPS remanent radiation the warm spots

    CERN Document Server

    Billen, R

    1998-01-01

    The remanent radiation in the SPS ring is measured after each operational period. We all know very well the "hot spots" in the dedicated regions for particle injection and extraction. So far, not a lot of attention has been paid to those regions where there are clear traces of radiation, without an obvious reason. From an operational point of view, these regions might be quite important, since they could reveal a specific problem. This paper will look into those "warm spots", their location in the SPS ring and the transverse plane in which the radiation originates. Some classification of typical problem classes is made, as well as hints to the possible origins of the radiation problems.

  17. Sustainable control of white spot disease

    DEFF Research Database (Denmark)

    Heinecke, Rasmus Demuth; Buchmann, Kurt

    White spot disease caused by the ciliate Ichthyophthirius multifiliis Fouquet, 1876 is a serious problem in freshwater aquaculture worldwide. This parasitosis is of frequent occurrence in both conventional earth pond fish farms and in fish farms using new high technology re-circulation systems...... all had significant influences on parasite survival. Strategic treatment using the environmentally friendly chemical sodium percarbonate in combination with continuous micro-filtering of the pond water is suggested for control and management of this parasitosis....

  18. Laser induced single spot oxidation of titanium

    Energy Technology Data Exchange (ETDEWEB)

    Jwad, Tahseen, E-mail: taj355@bham.ac.uk; Deng, Sunan; Butt, Haider; Dimov, S.

    2016-11-30

    Highlights: • A new high resolution laser induced oxidation (colouring) method is proposed (single spot oxidation). • The method is applied to control oxide films thicknesses and hence colours on titanium substrates in micro-scale. • The method enable imprinting high resolution coloured image on Ti substrate. • Optical and morphological periodic surface structures are also produced by an array of oxide spots using the proposed method. • Colour coding of two colours into one field is presented. - Abstract: Titanium oxides have a wide range of applications in industry, and they can be formed on pure titanium using different methods. Laser-induced oxidation is one of the most reliable methods due to its controllability and selectivity. Colour marking is one of the main applications of the oxidation process. However, the colourizing process based on laser scanning strategies is limited by the relative large processing area in comparison to the beam size. Single spot oxidation of titanium substrates is proposed in this research in order to increase the resolution of the processed area and also to address the requirements of potential new applications. The method is applied to produce oxide films with different thicknesses and hence colours on titanium substrates. High resolution colour image is imprinted on a sheet of pure titanium by converting its pixels’ colours into laser parameter settings. Optical and morphological periodic surface structures are also produced by an array of oxide spots and then analysed. Two colours have been coded into one field and the dependencies of the reflected colours on incident and azimuthal angles of the light are discussed. The findings are of interest to a range of application areas, as they can be used to imprint optical devices such as diffusers and Fresnel lenses on metallic surfaces as well as for colour marking.

  19. Laser induced single spot oxidation of titanium

    International Nuclear Information System (INIS)

    Jwad, Tahseen; Deng, Sunan; Butt, Haider; Dimov, S.

    2016-01-01

    Highlights: • A new high resolution laser induced oxidation (colouring) method is proposed (single spot oxidation). • The method is applied to control oxide films thicknesses and hence colours on titanium substrates in micro-scale. • The method enable imprinting high resolution coloured image on Ti substrate. • Optical and morphological periodic surface structures are also produced by an array of oxide spots using the proposed method. • Colour coding of two colours into one field is presented. - Abstract: Titanium oxides have a wide range of applications in industry, and they can be formed on pure titanium using different methods. Laser-induced oxidation is one of the most reliable methods due to its controllability and selectivity. Colour marking is one of the main applications of the oxidation process. However, the colourizing process based on laser scanning strategies is limited by the relative large processing area in comparison to the beam size. Single spot oxidation of titanium substrates is proposed in this research in order to increase the resolution of the processed area and also to address the requirements of potential new applications. The method is applied to produce oxide films with different thicknesses and hence colours on titanium substrates. High resolution colour image is imprinted on a sheet of pure titanium by converting its pixels’ colours into laser parameter settings. Optical and morphological periodic surface structures are also produced by an array of oxide spots and then analysed. Two colours have been coded into one field and the dependencies of the reflected colours on incident and azimuthal angles of the light are discussed. The findings are of interest to a range of application areas, as they can be used to imprint optical devices such as diffusers and Fresnel lenses on metallic surfaces as well as for colour marking.

  20. Heap hot spots visualization in Java

    OpenAIRE

    Mahdavi, Babak; Driesen, Karel

    2001-01-01

    Data memory (heap) management is a particularly important feature of the Java programming environment. The visualization of memory location in form of hot spots can help to see how the data cache is used during the execution of a program. The behavior of such executed program can be thus speculated. Through a series of experiments using Load and Store trace files, some pertinent aspect of data memory accessing, can be visualized, including the frequency of how often the Java virtual machine r...

  1. Forecasting European thermal coal spot prices

    Directory of Open Access Journals (Sweden)

    Alicja Krzemień

    2015-01-01

    Finally, in order to analyse the time series model performance a Generalized Regression Neural Network (GRNN was used and its performance compared against the whole AR(2 process. Empirical results obtained confirmed that there is no statistically significant difference between both methods. The GRNN analysis also allowed pointing out the main drivers that move the European Thermal Coal Spot prices: crude oil, USD/CNY change and supply side drivers.

  2. Mass spectrometric studies on the in vivo metabolism and excretion of SIRT1 activating drugs in rat urine, dried blood spots, and plasma samples for doping control purposes.

    Science.gov (United States)

    Höppner, Sebastian; Delahaut, Philippe; Schänzer, Wilhelm; Thevis, Mario

    2014-01-01

    The NAD(+) depending enzyme SIRT1 regulates the mitochondrial biogenesis, fat and glucose metabolism through catalyzing the deacetylation of several metabolism-related protein-substrates. Recently, synthetic activators of SIRT1 referred to as STACs (Sirtuin activating compounds, e.g. SRT2104) were identified and tested in clinical studies for the treatment of aging-related diseases such as type 2 diabetes, Alzheimer's and obesity. Although the mechanism of SIRT1 activation by small molecules has caused considerable controversy, STACs demonstrated a significant performance enhancement in mice experiments including an improvement of endurance, muscle strength, and locomotor behavior. Due to their potential to increase exercise tolerance in healthy individuals, SIRT1 activators are currently being monitored by anti-doping authorities. In the present study, the in vivo metabolic clearance of three SIRT1 activators was investigated in rats by the collection of urine, DBS (dried blood spots) and plasma samples following a single oral administration. The resulting metabolic products were studied by positive electrospray ionization - (tandem) mass spectrometry and confirmed by the comparison with in vitro generated metabolites using human and rat liver microsomal preparations. Subsequently, a screening procedure for five SIRT1 activators and the metabolite M1-SRT1720 in DBS specimens was developed. Liquid-liquid-extraction and liquid chromatography/tandem mass spectrometry was employed based on diagnostic ion transitions recorded in multiple reaction monitoring mode and two deuterated internal standards namely d8-SRT1720 and d8-M1-SRT1720 were utilized. The doping control assay was characterized with regard to specificity, limit of detection (10-50ng/ml), recovery (65-83%) and imprecision (7-20%) and ion suppression/enhancement effects (drug testing applications. Copyright © 2013 Elsevier B.V. All rights reserved.

  3. DNA-nanostructure-assembly by sequential spotting

    Directory of Open Access Journals (Sweden)

    Breitenstein Michael

    2011-11-01

    Full Text Available Abstract Background The ability to create nanostructures with biomolecules is one of the key elements in nanobiotechnology. One of the problems is the expensive and mostly custom made equipment which is needed for their development. We intended to reduce material costs and aimed at miniaturization of the necessary tools that are essential for nanofabrication. Thus we combined the capabilities of molecular ink lithography with DNA-self-assembling capabilities to arrange DNA in an independent array which allows addressing molecules in nanoscale dimensions. Results For the construction of DNA based nanostructures a method is presented that allows an arrangement of DNA strands in such a way that they can form a grid that only depends on the spotted pattern of the anchor molecules. An atomic force microscope (AFM has been used for molecular ink lithography to generate small spots. The sequential spotting process allows the immobilization of several different functional biomolecules with a single AFM-tip. This grid which delivers specific addresses for the prepared DNA-strand serves as a two-dimensional anchor to arrange the sequence according to the pattern. Once the DNA-nanoarray has been formed, it can be functionalized by PNA (peptide nucleic acid to incorporate advanced structures. Conclusions The production of DNA-nanoarrays is a promising task for nanobiotechnology. The described method allows convenient and low cost preparation of nanoarrays. PNA can be used for complex functionalization purposes as well as a structural element.

  4. A field trial of a PCR-based Mansonella ozzardi diagnosis assay detects high-levels of submicroscopic M. ozzardi infections in both venous blood samples and FTA card dried blood spots.

    Science.gov (United States)

    Medeiros, Jansen Fernandes; Almeida, Tatiana Amaral Pires; Silva, Lucyane Bastos Tavares; Rubio, Jose Miguel; Crainey, James Lee; Pessoa, Felipe Arley Costa; Luz, Sergio Luiz Bessa

    2015-05-20

    Mansonella ozzardi is a poorly understood human filarial parasite with a broad distribution throughout Latin America. Most of what is known about its parasitism has come from epidemiological studies that have estimated parasite incidence using light microscopy. Light microscopy can, however, miss lighter, submicroscopic, infections. In this study we have compared M. ozzardi incidence estimates made using light microscopy, with estimates made using PCR. 214 DNA extracts made from Large Volume Venous Blood Samples (LVVBS) were taken from volunteers from two study sites in the Rio Solimões region: Codajás [n = 109] and Tefé [n = 105] and were subsequently assayed for M. ozzardi parasitism using a diagnostic PCR (Mo-dPCR). Peripheral finger-prick blood samples were taken from the same individuals and used for microscopic examination. Finger-prick blood, taken from individuals from Tefé, was also used for the creation of FTAcard dried blood spots (DBS) that were subsequently subjected to Mo-dPCR. Overall M. ozzardi incidence estimates made with LVVBS PCRs were 1.8 times higher than those made using microscopy (44.9% [96/214] compared with 24.3% [52/214]) and 1.5 times higher than the PCR estimates made from FTAcard DBS (48/105 versus 31/105). PCR-based detection of FTAcard DBS proved 1.3 times more sensitive at diagnosing infections from peripheral blood samples than light microscopy did: detecting 24/105 compared with 31/105. PCR of LVVBS reported the fewest number of false negatives, detecting: 44 of 52 (84.6%) individuals diagnosed by microscopy; 27 of 31 (87.1%) of those diagnosed positive from DBSs and 17 out of 18 (94.4%) of those diagnosed as positive by both alternative methodologies. In this study, Mo-dPCR of LVVBS was by far the most sensitive method of detecting M. ozzardi infections and detected submicroscopic infections. Mo-dPCR FTAcard DBS also provided a more sensitive test for M. ozzardi diagnosis than light microscopy based diagnosis did and

  5. Nanotopographic characterization of spotted micro arrays on polyvinyl alcohol films by high-resolution long-range nanoprofiling.

    Science.gov (United States)

    Thete, Aniket R; Gross, G Alexander; Hausotte, Tino; Jäger, Gerd; Dorozhovets, Nataliya; Köhler, J Michael

    2009-01-01

    The nanopositioning and nanomeasuring machine was applied for the nanotopographic characterization of polymer micro spot arrays of fluorimetric chemochips. Chemochips are arrays of fluorescence dyes in a hydrogel matrix with different response behaviors of chemical components determination of chemical and physico-chemical properties of analytes by a pattern recognition approach. For the characterization and quality control of the spots, a nanometer resolution is needed over a scan range of several millimeters. This challenge could be met by use of a scanning probe sensor in connection with a laser interferometer controlled high-precision positioning and measuring device. This way, topographic scans with the resolution of atomic force microscope could be achieved over these demandingly large ranges. The technique was used in order to determine the quality of thin film micro spots made from fluorescence dye solutions on preformed polymer films and also tested for characterization of monomolecular films in the form of micro spots. The nanotopographic measurements reflect the strong influence of solvent/matrix interaction, wetting, swelling and material transport during the application of picoliter droplets in the spotting process. The measurement clarifies the reason for the formation of roughness in the nanometer range by nano-crystal formation in the upper part of polymer film and the rim formation of micro spots during solvent evaporation. The studies show the effect of application of different numbers of droplets in a dispensing series for spot formation and prove the high importance of polymer/solvent interaction for the quality of formed micro spots as well as for spot arrays of monomolecular films. Copyright (c) 2009 Wiley Periodicals, Inc.

  6. Laparoscopic ovum pick-up in spotted paca ( Cuniculus pacas

    Directory of Open Access Journals (Sweden)

    F.F.P.C. Barros

    2016-08-01

    Full Text Available ABSTRACT The aim of this work is study the laparoscopic ovum pick-up (LapOPU technique in spotted paca, describing surgery details, complications and oocyte recovery rate. Nine healthy adult non-pregnant captive females were used, in a total of 39 procedures. When the surgical plane of anaesthesia was achieved, the females were positioned at 20º Trendelenburg. Three 6mm trocars were placed on right and left inguinal and hypogastric regions. Abdomen was inflated with CO2 and the intra-abdominal pressure was stablished in 10mmHg. Follicular punctures were performed moving the ovaries with atraumatic forceps. For punctures, an 18-gauge 3.5 inch long needle attached to a vacuum system with pressure not exceeding 65mmHg was used. Oocytes were recovered into 50mL centrifuge tubes with media composed of PBS supplemented with 10 IU/mL of heparin and kept at 36°C. R Software was used for statistical analysis. Data normality distribution (Shapiro test and variances homoscedasticity (Bartlett test were tested and descriptive statistics (mean±SD was used to present the results. It was only possible to perform LapOPU in 30 of 39 laparoscopies (76.92%. The surgical total time was 37.34 ± 18.53 minutes. The total number of visualized follicles, aspirated follicles, and retrieved oocytes were 502, 415, and 155, respectively. And the same parameters per animal were: 14.34 ± 12.23, 11.86 ± 10.03, and 4.43 ± 4.69 respectively. Oocyte recovery rate was 32.56 ± 27.32%. In conclusion, caudal positioning of portals with slight triangulation allows good viewing of the abdominal cavity and eases the manipulation of the ovaries. Thus this described LapOPU technique is feasible in spotted paca and easy to perform.

  7. Superluminal Sweeping Spot Pair Events in Astronomical Settings

    Science.gov (United States)

    Nemiroff, Robert J.

    2015-01-01

    Sweeping beams of light can cast spots that move superluminally across scattering surfaces. Such faster-than-light speeds are well-known phenomena that do not violate special relativity. It is shown that under certain circumstances, superluminal spot pair creation and annihilation events can occur that provide unique information to observers. These spot pair events are not particle pair events -- they are the sudden creation or annihilation of a pair of relatively illuminated spots on a scattering surface. Astronomical settings where superluminal spot pairs might be found include Earth's Moon, passing asteroids, pulsars, and variable nebula. Potentially recoverable information includes three dimensional imaging, relative geometric size factors, and distances.

  8. 7 CFR 28.414 - Strict Low Middling Light Spotted Color.

    Science.gov (United States)

    2010-01-01

    ... CONTAINER REGULATIONS COTTON CLASSING, TESTING, AND STANDARDS Standards Light Spotted Cotton § 28.414 Strict Low Middling Light Spotted Color. Strict Low Middling Light Spotted Color is color which in spot or...

  9. Time Resolved X-Ray Spot Size Diagnostic

    CERN Document Server

    Richardson, Roger; Falabella, Steven; Guethlein, Gary; Raymond, Brett; Weir, John

    2005-01-01

    A diagnostic was developed for the determination of temporal history of an X-ray spot. A pair of thin (0.5 mm) slits image the x-ray spot to a fast scintillator which is coupled to a fast detector, thus sampling a slice of the X-Ray spot. Two other scintillator/detectors are used to determine the position of the spot and total forward dose. The slit signal is normalized to the dose and the resulting signal is analyzed to get the spot size. The position information is used to compensate for small changes due to spot motion and misalignment. The time resolution of the diagnostic is about 1 ns and measures spots from 0.5 mm to over 3 mm. The theory and equations used to calculate spot size and position are presented, as well as data. The calculations assume a symmetric, Gaussian spot. The spot data is generated by the ETA II accelerator, a 2kA, 5.5 MeV, 60ns electron beam focused on a Tantalum target. The spot generated is typically about 1 mm FWHM. Comparisons are made to an X-ray pinhole camera which images th...

  10. A novel tandem mass spectrometry method for first-line screening of mainly beta-thalassemia from dried blood spots.

    Science.gov (United States)

    Yu, Chaowen; Huang, Shuodan; Wang, Ming; Zhang, Juan; Liu, Hao; Yuan, Zhaojian; Wang, Xingbin; He, Xiaoyan; Wang, Jie; Zou, Lin

    2017-02-10

    Traditional methods for thalassemia screening are time-consuming and easily affected by cell hemolysis or hemoglobin degradation in stored blood samples. Tandem mass spectrometry (MS/MS) proved to be an effective technology for sickle cell disorders (SCD) screening. Here, we developed a novel MS/MS method for β-thalassemia screening from dried blood spots (DBS). Stable isotopic-labeled peptides were used as internal standards for quantification and calculation of the α:β-globin ratios. We used the α:β-globin ratio cutoffs to differentiate between normal individuals and patients with thalassemia. About 781 patients and 300 normal individuals were analyzed. The α:β-globin ratios showed significant difference between normal and β-thalassemia patients (Pthalassemia mutation. In the parallel study, all cases screened for suspected thalassemia from six hundred DBS samples by using this MS/MS method were successfully confirmed by genotyping. The intra-assay and inter-assay CVs of the ratios ranged from 2.4% to 3.9% and 4.7% to 7.1%, and there was no significant sample carryover or matrix effect for this MS/MS method. Combined with SCD screening, this MS/MS method could be used as a first-line screening assay for both structural and expression abnormalities of human hemoglobin. Traditional methods for thalassemia screening were depending on the structural integrity of tetramers and could be affected by hemolysis and degradation of whole blood samples, especially when stored. We used proteospecific peptides produced by the tryptic digestion of each globin to evaluate the production ratio between α- and β-globin chains, which turned out to be quite stable even when stored for more than two months. Though most of the peptides were specific to α-globin or β-globin, we only chose four most informative peptides and its stable isotopic-labeled peptides as internal standards for analysis, which could obtain a high accuracy. Currently, we are the first to address the

  11. Improved simulation method of automotive spot weld failure with an account of the mechanical properties of spot welds

    Science.gov (United States)

    Wu, H.; Meng, X. M.; Fang, R.; Huang, Y. F.; Zhan, S.

    2017-12-01

    In this paper, the microstructure and mechanical properties of spot weld were studied, the hardness of nugget and heat affected zone (HAZ) were also tested by metallographic microscope and microhardness tester. The strength of the spot weld with the different parts' area has been characterized. According to the experiments result, CAE model of spot weld with HAZ structure was established, and simulation results of different lap-shear CAE models were analyzed. The results show that the spot weld model which contained the HAZ has good performance and more suitable for engineering application in spot weld simulation.

  12. Monte Carlo studies on the influence of focal spot size and intensity distribution on spatial resolution in magnification mammography

    Energy Technology Data Exchange (ETDEWEB)

    Koutalonis, M; Delis, H; Spyrou, G; Costaridou, L; Panayiotakis, G [University of Patras, School of Medicine, Department of Medical Physics, 265 00 Patras (Greece); Tzanakos, G [University of Athens, Department of Physics, Div. Nucl. and Particle Physics, 157 71 Athens (Greece)], E-mail: panayiot@upatras.gr

    2008-03-07

    Magnification is a special technique applied in mammography in cases where breast complaints have already been noticed, aiming to examine a specific area of the breast. Small-sized focal spots are essential in such techniques in order to reduce the resultant geometrical unsharpness. The x-ray intensity distribution of the focal spot is another crucial parameter for such a technique as it affects the mammographic resolution. In this study a Monte Carlo simulation model is utilized, in order to examine the effect of a wide range of focal spot sizes and three representative intensity distributions on spatial resolution under magnification. A thick sharp edge consisting of lead, non-transparent to x-rays was imaged under various conditions for this purpose, and the corresponding spatial resolution was calculated through the modulation transfer function (MTF). Results demonstrate that focal spots larger than 0.10 mm can mainly be used for low degrees of magnification, especially when combined with double peak Gaussian intensity distribution of the focal spot (sum of two single peak Gaussian distributions with different centers), as the resultant spatial resolution is not as high as the corresponding from smaller foci or uniform and single peak Gaussian distributions. Moreover, for the degrees of magnification usually utilized in clinical practice they do not reach the acceptable limit of 12 lp mm{sup -1}. The replacement of the x-ray tube when the focal spot starts being destroyed is very crucial as the possible alteration of single peak Gaussian distribution to double peak Gaussian results in the degradation of spatial resolution. A focal spot of 0.10 mm or smaller, combined with single peak Gaussian intensity distribution, can be considered appropriate even for higher degrees of magnification and its use can contribute in the effort to optimize the magnification views in mammography.

  13. Monte Carlo studies on the influence of focal spot size and intensity distribution on spatial resolution in magnification mammography

    Science.gov (United States)

    Koutalonis, M.; Delis, H.; Spyrou, G.; Costaridou, L.; Tzanakos, G.; Panayiotakis, G.

    2008-03-01

    Magnification is a special technique applied in mammography in cases where breast complaints have already been noticed, aiming to examine a specific area of the breast. Small-sized focal spots are essential in such techniques in order to reduce the resultant geometrical unsharpness. The x-ray intensity distribution of the focal spot is another crucial parameter for such a technique as it affects the mammographic resolution. In this study a Monte Carlo simulation model is utilized, in order to examine the effect of a wide range of focal spot sizes and three representative intensity distributions on spatial resolution under magnification. A thick sharp edge consisting of lead, non-transparent to x-rays was imaged under various conditions for this purpose, and the corresponding spatial resolution was calculated through the modulation transfer function (MTF). Results demonstrate that focal spots larger than 0.10 mm can mainly be used for low degrees of magnification, especially when combined with double peak Gaussian intensity distribution of the focal spot (sum of two single peak Gaussian distributions with different centers), as the resultant spatial resolution is not as high as the corresponding from smaller foci or uniform and single peak Gaussian distributions. Moreover, for the degrees of magnification usually utilized in clinical practice they do not reach the acceptable limit of 12 lp mm-1. The replacement of the x-ray tube when the focal spot starts being destroyed is very crucial as the possible alteration of single peak Gaussian distribution to double peak Gaussian results in the degradation of spatial resolution. A focal spot of 0.10 mm or smaller, combined with single peak Gaussian intensity distribution, can be considered appropriate even for higher degrees of magnification and its use can contribute in the effort to optimize the magnification views in mammography.

  14. Laser spot detection based on reaction diffusion

    Czech Academy of Sciences Publication Activity Database

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

    2016-01-01

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

  15. On cold spots in tumor subvolumes

    International Nuclear Information System (INIS)

    Tome, Wolfgang A.; Fowler, Jack F.

    2002-01-01

    Losses in tumor control are estimated for cold spots of various 'sizes' and degrees of 'cold dose'. This question is important in the context of intensity modulated radiotherapy where differential dose-volume histograms (DVHs) for targets that abut a critical structure often exhibit a cold dose tail. This can be detrimental to tumor control probability (TCP) for fractions of cold volumes even as small as 1%, if the cold dose is lower than the prescribed dose by substantially more than 10%. The Niemierko-Goitein linear-quadratic algorithm with γ 50 slope 1-3 was used to study the effect of cold spots of various degrees (dose deficit below the prescription dose) and size (fractional volume of the cold dose). A two-bin model DVH has been constructed in which the cold dose bin is allowed to vary from a dose deficit of 1%-50% below prescription dose and to have volumes varying from 1% to 90%. In order to study and quantify the effect of a small volume of cold dose on TCP and effective uniform dose (EUD), a four-bin DVH model has been constructed in which the lowest dose bin, which has a fractional volume of 1%, is allowed to vary from 10% to 45% dose deficit below prescription dose. The highest dose bin represents a simultaneous boost. For fixed size of the cold spot the calculated values of TCP decreased rapidly with increasing degrees of cold dose for any size of the cold spot, even as small as 1% fractional volume. For the four-subvolume model, in which the highest dose bin has a fractional volume of 80% and is set at a boost dose of 10% above prescription dose, it is found that the loss in TCP and EUD is moderate as long as the cold 1% subvolume has a deficit less than approximately 20%. However, as the dose deficit in the 1% subvolume bin increases further it drives TCP and EUD rapidly down and can lead to a serious loss in TCP and EUD. Since a dose deficit to a 1% volume of the target that is larger than 20% of the prescription dose may lead to serious loss of

  16. The fractal nature of vacuum arc cathode spots

    International Nuclear Information System (INIS)

    Anders, Andre

    2005-01-01

    Cathode spot phenomena show many features of fractals, for example self-similar patterns in the emitted light and arc erosion traces. Although there have been hints on the fractal nature of cathode spots in the literature, the fractal approach to spot interpretation is underutilized. In this work, a brief review of spot properties is given, touching the differences between spot type 1 (on cathodes surfaces with dielectric layers) and spot type 2 (on metallic, clean surfaces) as well as the known spot fragment or cell structure. The basic properties of self-similarity, power laws, random colored noise, and fractals are introduced. Several points of evidence for the fractal nature of spots are provided. Specifically power laws are identified as signature of fractal properties, such as spectral power of noisy arc parameters (ion current, arc voltage, etc) obtained by fast Fourier transform. It is shown that fractal properties can be observed down to the cutoff by measurement resolution or occurrence of elementary steps in physical processes. Random walk models of cathode spot motion are well established: they go asymptotically to Brownian motion for infinitesimal step width. The power spectrum of the arc voltage noise falls as 1/f 2 , where f is frequency, supporting a fractal spot model associated with Brownian motion

  17. Advanced spot quality analysis in two-colour microarray experiments

    Directory of Open Access Journals (Sweden)

    Vetter Guillaume

    2008-09-01

    Full Text Available Abstract Background Image analysis of microarrays and, in particular, spot quantification and spot quality control, is one of the most important steps in statistical analysis of microarray data. Recent methods of spot quality control are still in early age of development, often leading to underestimation of true positive microarray features and, consequently, to loss of important biological information. Therefore, improving and standardizing the statistical approaches of spot quality control are essential to facilitate the overall analysis of microarray data and subsequent extraction of biological information. Findings We evaluated the performance of two image analysis packages MAIA and GenePix (GP using two complementary experimental approaches with a focus on the statistical analysis of spot quality factors. First, we developed control microarrays with a priori known fluorescence ratios to verify the accuracy and precision of the ratio estimation of signal intensities. Next, we developed advanced semi-automatic protocols of spot quality evaluation in MAIA and GP and compared their performance with available facilities of spot quantitative filtering in GP. We evaluated these algorithms for standardised spot quality analysis in a whole-genome microarray experiment assessing well-characterised transcriptional modifications induced by the transcription regulator SNAI1. Using a set of RT-PCR or qRT-PCR validated microarray data, we found that the semi-automatic protocol of spot quality control we developed with MAIA allowed recovering approximately 13% more spots and 38% more differentially expressed genes (at FDR = 5% than GP with default spot filtering conditions. Conclusion Careful control of spot quality characteristics with advanced spot quality evaluation can significantly increase the amount of confident and accurate data resulting in more meaningful biological conclusions.

  18. Cold Spots in Neonatal Incubators Are Hot Spots for Microbial Contamination▿

    Science.gov (United States)

    de Goffau, Marcus C.; Bergman, Klasien A.; de Vries, Hendrik J.; Meessen, Nico E. L.; Degener, John E.; van Dijl, Jan Maarten; Harmsen, Hermie J. M.

    2011-01-01

    Thermal stability is essential for the survival and well-being of preterm neonates. This is achieved in neonatal incubators by raising the ambient temperature and humidity to sufficiently high levels. However, potentially pathogenic microorganisms also can thrive in such warm and humid environments. We therefore investigated whether the level of microbial contamination (i.e., the bacterial load) inside neonatal incubators can be predicted on the basis of their average temperature and relative humidity settings, paying special attention to local temperature differences. Swab samples were taken from the warmest and coldest spots found within Caleo incubators, and these were plated to determine the number of microbial CFU per location. In incubators with high average temperature (≥34°C) and relative humidity (≥60%) values, the level of microbial contamination was significantly higher at cold spots than at hot spots. This relates to the fact that the local equilibrium relative humidity at cold spots is sufficiently high to sustain microbial growth. The abundance of staphylococci, which are the main causative agents of late-onset sepsis in preterm neonates, was found to be elevated significantly in cold areas. These findings can be used to improve basic incubator hygiene. PMID:22003021

  19. Cold spots in neonatal incubators are hot spots for microbial contamination.

    Science.gov (United States)

    de Goffau, Marcus C; Bergman, Klasien A; de Vries, Hendrik J; Meessen, Nico E L; Degener, John E; van Dijl, Jan Maarten; Harmsen, Hermie J M

    2011-12-01

    Thermal stability is essential for the survival and well-being of preterm neonates. This is achieved in neonatal incubators by raising the ambient temperature and humidity to sufficiently high levels. However, potentially pathogenic microorganisms also can thrive in such warm and humid environments. We therefore investigated whether the level of microbial contamination (i.e., the bacterial load) inside neonatal incubators can be predicted on the basis of their average temperature and relative humidity settings, paying special attention to local temperature differences. Swab samples were taken from the warmest and coldest spots found within Caleo incubators, and these were plated to determine the number of microbial CFU per location. In incubators with high average temperature (≥ 34°C) and relative humidity (≥ 60%) values, the level of microbial contamination was significantly higher at cold spots than at hot spots. This relates to the fact that the local equilibrium relative humidity at cold spots is sufficiently high to sustain microbial growth. The abundance of staphylococci, which are the main causative agents of late-onset sepsis in preterm neonates, was found to be elevated significantly in cold areas. These findings can be used to improve basic incubator hygiene.

  20. Hot Spots Detection of Operating PV Arrays through IR Thermal Image Using Method Based on Curve Fitting of Gray Histogram

    Directory of Open Access Journals (Sweden)

    Jiang Lin

    2016-01-01

    Full Text Available The overall efficiency of PV arrays is affected by hot spots which should be detected and diagnosed by applying responsible monitoring techniques. The method using the IR thermal image to detect hot spots has been studied as a direct, noncontact, nondestructive technique. However, IR thermal images suffer from relatively high stochastic noise and non-uniformity clutter, so the conventional methods of image processing are not effective. The paper proposes a method to detect hotspots based on curve fitting of gray histogram. The result of MATLAB simulation proves the method proposed in the paper is effective to detect the hot spots suppressing the noise generated during the process of image acquisition.

  1. Evidence for the spotting hypothesis in gymnasts.

    Science.gov (United States)

    Heinen, Thomas

    2011-04-01

    The goal of this study was to investigate the visual spotting hypothesis in 10 experts and 10 apprentices as they perform back aerial somersaults from a standing position with no preparatory jumps (short flight duration condition) and after some preparatory jumps with a flight time of 1s (long flight duration condition). Differences in gaze behavior and kinematics were expected between experts and apprentices and between experimental conditions. Gaze behavior was measured using a portable and wireless eye-tracking system in combination with a movement-analysis system. Experts exhibited a smaller landing deviation from the middle of the trampoline bed than apprentices. Experts showed higher fixation ratios during the take-off and flight phase. Experts exhibited no blinks in any of the somersaults in both conditions, whereas apprentices showed significant blink ratios in both experimental conditions. The findings suggest that gymnasts can use visual spotting during the back aerial somersault, even when the time of flight is delimited. We conclude that knowledge about gaze-movement relationships may help coaches develop specific training programs in the learning process of the back aerial somersault.

  2. Hot spot exercise: 1975 (HSX-75)

    International Nuclear Information System (INIS)

    Trolan, R.T.; Wilson, R.L.; Jessen, F.W.

    1976-01-01

    A special unannounced exercise, called HOT SPOT Exercise--1975 (HSX-75), was prepared to test the general capability of the LLL ALERT Program to activate and deploy the LLL and Sandia Laboratory, Livermore (SLL) component of the ERDA/ARG. The exercise activities were limited to the LLL facilities in Livermore and the Site 300 explosive test facility located approximately 15 miles southeast of Livermore. The exercise simulated an accident at a U.S. Army storage facility (Site 300). The simulated accident involved two LLL designed weapons (W-70). One weapon was dropped during unloading operations and ignited the gas tank of the weapon transporter. The subsequent fire caused a low-order detonation of the high explosive component. The fire caused dispersal of fissile material downwind from the site. A second weapon was damaged in the explosion by fragments from the first weapon. The extent of damage to the second weapon was initially unknown. The exercise was conducted on September 23, 1975. A complete description of the specific nature of the simulated accident is contained in the scenario. Umpires were assigned to evaluate and subsequently report on the effectiveness of the response. All test objectives were accomplished. The following appendices are included: operational safety procedures, photographs and site map, HOT SPOT equipment, atmospheric release advisory capability, personnel list, chronology of events, and critique comments

  3. Senzorové uzly Java Sun SPOT

    OpenAIRE

    Malina, Karel

    2010-01-01

    Tato bakalářská práce se zabývá využitím senzorových uzlů Java Sun Spot pro vícebodové bezdrátové sledování teploty a její regulace pomocí těchto uzlů. V teoretické části je uveden popis, složení a ovládání senzorových uzlů Java Sun Spot. V praktické části jsou uvedeny naprogramované aplikace, ve vývojovém prostředí NetBeans, pro bezdrátové sledování teploty, kapacity baterie a jejich zobrazení na hostitelském počítači ve formě grafu. Ve druhé části praktické části je popsán způsob regulace t...

  4. Resistance to leaf spot disease in peanut

    International Nuclear Information System (INIS)

    Soriano, J.D.

    1988-01-01

    Full text: Leaf spot disease causes defoliation of peanut plants during pod development thereby reducing yield. To induce mutations for resistance to the disease, dormant seeds of peanut were irradiated with 10-40 kR gamma rays with pre- and post-irradiation treatments to minimize radiation damage. Spores of the causal fungi, Cercospora arachidicola Hori and Cercosporidium personatum (B and C) Deigh., were cultured under asceptic conditions in PDA medium with 2-3 drops of 10% table salt solution to enhance development of spores. The first two leaves of M 2 seedlings were hand-inoculated two or three times in the field at one week intervals. Out of a total of 2,453 M 2 seedlings inoculated thrice, 9 plants showed complete resistance based on degree of infection. However, after recurrent selection, only 3 M 5 lines gave complete resistance, the rest exhibiting only intermediate resistance. The disease resistant lines yielded almost twice as much as several commercial varieties due to extensive leaf defoliation in the latter. One of the mutant lines is being crossed with some popular susceptible varieties. Inheritance studies showed that leaf spot resistance is governed by two recessive mutant genes acting complementary. The F 2 ratio was close to 15:1. The mutant lines are presently evaluated through the Bureau of Plant Industry before seeds are distributed to peanut growers. (author)

  5. A new index for electricity spot markets

    International Nuclear Information System (INIS)

    Falbo, Paolo; Fattore, Marco; Stefani, Silvana

    2010-01-01

    Different indexes are used in electricity markets worldwide to represent the daily behavior of spot prices. However, the peculiarities of these markets require a careful choice of the index, based on mathematical formulation and its statistical properties. Choosing a bad index may influence the financial policies of market players, since derivative pricing and hedging performance can be deeply affected. In this paper with an initial theoretical analysis, we intend to show that the most widely used indexes (simple arithmetic average and weighted average with current volumes) are poor representatives of the spot market. We will then perform an analysis of the hedging strategy on a derivative instrument (an Asian option) written on a reference index. The resulting simulations, applied to OMEL (Spain) and EEX (Germany), are sufficiently clear cut to suggest that the decision to adopt an index to represent properly a market must be taken very carefully. Finally we will propose a new index (FAST index) and, after comparing it with the previous indexes, will show that both theoretically and practically this index can be taken as a good electricity market synthetic indicator. (author)

  6. A New Method to Quantify Ifosfamide Blood Levels Using Dried Blood Spots and UPLC-MS/MS in Paediatric Patients with Embryonic Solid Tumours.

    Directory of Open Access Journals (Sweden)

    Luz-María Torres

    Full Text Available Ifosfamide blood concentrations are necessary to monitor its therapeutic response, avoiding any adverse effect. We developed and validated an analytical method by UPLC-MS/MS to quantify ifosfamide in dried blood spots (DBS. Blood samples were collected on Whatman 903® filter paper cards. Five 3 mm disks were punched out from each dried blood spot. Acetonitrile and ethyl acetate were used for drug extraction. Chromatographic separation was carried out in an Acquity UPLC equipment with a BEH-C18 column, 2.1 x 100 mm, 1.7 μm (Waters®. The mobile phase consisted in 5 mM ammonium formate and methanol:acetonitrile (40:48:12 v/v/v at 0.2 mL/min. LC-MS/MS detection was done by ESI+ and multiple reaction mode monitoring, ionic transitions were m/z1+ 260.99 > 91.63 for ifosfamide and 261.00 > 139.90 for cyclophosphamide (internal standard. This method was linear within a 100-10000 ng/mL range and it was accurate, precise and selective. Ifosfamide samples in DBS were stable for up to 52 days at -80°C. The procedure was tested in 14 patients, ages 1 month to 17 years (9 males and 5 females, with embryonic tumours treated with ifosfamide, alone or combined, at a public tertiary referral hospital. Ifosfamide blood levels ranged from 11.1 to 39.7 μmol/L at 12 hours after the last infusion, while 24-hour levels ranged from 0.7-19.7 μmol/L. The median at 12 hours was 19.5 μmol/L (Q25 14.4-Q75 29.0 and 3.8 μmol/L (Q25 1.5-Q75 9.9 at 24 hours, p<0.001. This method is feasible to determine ifosfamide plasma levels in paediatric patients.

  7. Smart SERS Hot Spots: Single Molecules Can Be Positioned in a Plasmonic Nanojunction Using Host-Guest Chemistry.

    Science.gov (United States)

    Kim, Nam Hoon; Hwang, Wooseup; Baek, Kangkyun; Rohman, Md Rumum; Kim, Jeehong; Kim, Hyun Woo; Mun, Jungho; Lee, So Young; Yun, Gyeongwon; Murray, James; Ha, Ji Won; Rho, Junsuk; Moskovits, Martin; Kim, Kimoon

    2018-03-01

    Single-molecule surface-enhanced Raman spectroscopy (SERS) offers new opportunities for exploring the complex chemical and biological processes that cannot be easily probed using ensemble techniques. However, the ability to place the single molecule of interest reliably within a hot spot, to enable its analysis at the single-molecule level, remains challenging. Here we describe a novel strategy for locating and securing a single target analyte in a SERS hot spot at a plasmonic nanojunction. The "smart" hot spot was generated by employing a thiol-functionalized cucurbit[6]uril (CB[6]) as a molecular spacer linking a silver nanoparticle to a metal substrate. This approach also permits one to study molecules chemically reluctant to enter the hot spot, by conjugating them to a moiety, such as spermine, that has a high affinity for CB[6]. The hot spot can accommodate at most a few, and often only a single, analyte molecule. Bianalyte experiments revealed that one can reproducibly treat the SERS substrate such that 96% of the hot spots contain a single analyte molecule. Furthermore, by utilizing a series of molecules each consisting of spermine bound to perylene bisimide, a bright SERS molecule, with polymethylene linkers of varying lengths, the SERS intensity as a function of distance from the center of the hot spot could be measured. The SERS enhancement was found to decrease as 1 over the square of the distance from the center of the hot spot, and the single-molecule SERS cross sections were found to increase with AgNP diameter.

  8. Hot spot formation on different tokamak wall materials

    International Nuclear Information System (INIS)

    Nedospasov, A.V.; Bezlyudny, I.V.

    1998-01-01

    The thermal contraction phenomenon and generation of 'hot spots' due to thermoemission were described. The paper consider non-linear stages of heat contraction on the graphite, beryllium, tungsten and vanadium wall. It is shown that on the beryllium surface hot spot can't appear due to strong cooling by sublimation. For other materials the conditions of hot spot appearance due to local superheating of the wall have been calculated and their parameters were found: critical surface temperature, size of spots and their temperature profiles, heat fluxes from plasma to the spots. It have been calculated fluxes of sublimating materials from spots to the plasma. It is noticed that nominal temperature of the grafite divertor plate, accepted in ITER's project to being equal 1500 C, is lower then critical temperature of the development heat contraction due to thermoemission. (orig.)

  9. Combining geometric matching with SVM to improve symbol spotting

    Science.gov (United States)

    Nayef, Nibal; Breuel, Thomas M.

    2013-01-01

    Symbol spotting is important for automatic interpretation of technical line drawings. Current spotting methods are not reliable enough for such tasks due to low precision rates. In this paper, we combine a geometric matching-based spotting method with an SVM classifier to improve the precision of the spotting. In symbol spotting, a query symbol is to be located within a line drawing. Candidate matches can be found, however, the found matches may be true or false. To distinguish a false match, an SVM classifier is used. The classifier is trained on true and false matches of a query symbol. The matches are represented as vectors that indicate the qualities of how well the query features are matched, those qualities are obtained via geometric matching. Using the classification, the precision of the spotting improved from an average of 76.6% to an average of 97.2% on a database of technical line drawings.

  10. Spot: A Programming Language for Verified Flight Software

    Science.gov (United States)

    Bocchino, Robert L., Jr.; Gamble, Edward; Gostelow, Kim P.; Some, Raphael R.

    2014-01-01

    The C programming language is widely used for programming space flight software and other safety-critical real time systems. C, however, is far from ideal for this purpose: as is well known, it is both low-level and unsafe. This paper describes Spot, a language derived from C for programming space flight systems. Spot aims to maintain compatibility with existing C code while improving the language and supporting verification with the SPIN model checker. The major features of Spot include actor-based concurrency, distributed state with message passing and transactional updates, and annotations for testing and verification. Spot also supports domain-specific annotations for managing spacecraft state, e.g., communicating telemetry information to the ground. We describe the motivation and design rationale for Spot, give an overview of the design, provide examples of Spot's capabilities, and discuss the current status of the implementation.

  11. CFD analysis of hot spot formation through a fixed bed reactor of Fischer-Tropsch synthesis

    Directory of Open Access Journals (Sweden)

    Hamed Aligolzadeh

    2015-12-01

    Full Text Available One of the interesting methods for conversion of synthesis gas to heavy hydrocarbons is Fischer–Tropsch process. The process has some bottlenecks, such as hot spot formation and low degree of conversion. In this work, computational fluid dynamics technique was used to simulate conversion of synthetic gas and product distribution. Also, hot spot formation in the catalytic fixed-bed reactor was investigated in several runs. Simulation results indicated that hot spot formation occurred more likely in the early and middle part of reactor due to high reaction rates. Based on the simulation results, the temperature of hot spots increased with increase in the inlet temperature as well as pressure. Among the many CFD runs conducted, it is found that the optimal temperature and pressure for Fischer–Tropsch synthesis are 565 K and 20 bar, respectively. As it seems that the reactor shall work very well under optimal conditions, the reaction rates and catalyst duration would simultaneously be maximum .

  12. HMM filtering and parameter estimation of an electricity spot price model

    International Nuclear Information System (INIS)

    Erlwein, Christina; Benth, Fred Espen; Mamon, Rogemar

    2010-01-01

    In this paper we develop a model for electricity spot price dynamics. The spot price is assumed to follow an exponential Ornstein-Uhlenbeck (OU) process with an added compound Poisson process. In this way, the model allows for mean-reversion and possible jumps. All parameters are modulated by a hidden Markov chain in discrete time. They are able to switch between different economic regimes representing the interaction of various factors. Through the application of reference probability technique, adaptive filters are derived, which in turn, provide optimal estimates for the state of the Markov chain and related quantities of the observation process. The EM algorithm is applied to find optimal estimates of the model parameters in terms of the recursive filters. We implement this self-calibrating model on a deseasonalised series of daily spot electricity prices from the Nordic exchange Nord Pool. On the basis of one-step ahead forecasts, we found that the model is able to capture the empirical characteristics of Nord Pool spot prices. (author)

  13. Bier’s spots with onset in childhood*

    Science.gov (United States)

    Portocarrero, Larissa Karine Leite; Saraiva, Maria Isabel Ramos; Barbosa, Marcella Amaral Horta; Veronez, Isis Suga; Swiczar, Bethania Cabral Cavalli; Valente, Neusa Yuriko Sakai

    2016-01-01

    Bier spots are small, irregular, hypopigmented macules that are usually found on the arms and legs. The macules disappear when the limb is raised. Bier spots have been reported in association with a number of conditions but there is no consistent association to specific desease. Although they usually affect young adults, we report a case of Bier spots that began in childhood. As an asymptomatic and possibly transitional condition, the disease does not require treatment. PMID:28300906

  14. Dynamic characterization of the CT angiographic 'spot sign'.

    Directory of Open Access Journals (Sweden)

    Santanu Chakraborty

    Full Text Available BACKGROUND AND PURPOSE: Standard (static CT angiography is used to identify the intracerebral hemorrhage (ICH spot sign. We used dynamic CT-angiography to describe spot sign characteristics and measurement parameters over 60-seconds of image acquisition. METHODS: We prospectively identified consecutive patients presenting with acute ICH within 4.5 hours of symptom onset, and collected whole brain dynamic CT-angiography (dCTA. Spot parameters (earliest appearance, duration, maximum Hounsfield unit (HU, time to maximum HU, time to spot diagnostic definition, spot volume and hematoma volumes were measured using volumetric analysis software. RESULT: We enrolled 34 patients: three were excluded due to secondary causes of ICH. Of the remaining 31 patients there were 18 females (58% with median age 70 (range 47-86 and baseline hematoma volume 33 ml (range 0.7-103 ml. Positive dCTA spot sign was present in 13 patients (42% visualized as an expanding 3-dimensional structure temporally evolving its morphology over the scan period. Median time to spot appearance was 21 s (range 15-35 seconds. This method allowed tracking of spots evolution until the end of venous phase (active extravasation with median duration of 39 s (range 25-45 seconds. The average density and time to maximum density was 204HU and 30.8 s (range 23-31 s respectively. Median time to spot diagnosis was 20.8 s using either 100 or 120HU definitions. CONCLUSION: Dynamic CTA allows a 3-dimensional assessment of spot sign formation during acute ICH, and captured higher spot sign prevalence than previously reported. This is the first study to describe and quantify spot sign characteristics using dCTA; these can be used in ongoing and upcoming ICH studies.

  15. Insights from ecological niche modeling on the taxonomic distinction and niche differentiation between the black-spotted and red-spotted tokay geckoes (Gekko gecko)

    OpenAIRE

    Zhang, Yueyun; Chen, Chongtao; Li, Li; Zhao, Chengjian; Chen, Weicai; Huang, Yong

    2014-01-01

    The black-spotted tokay and the red-spotted tokay are morphologically distinct and have largely allopatric distributions. The black-spotted tokay is characterized by a small body size and dark skin with sundry spots, while the red-spotted tokay has a relatively large body size and red spots. Based on morphological, karyotypic, genetic, and distribution differences, recent studies suggested their species status; however, their classifications remain controversial, and additional data such as e...

  16. Wood ant nests as hot spots of carbon dioxide production and cold spots of methane oxidation in temperate forests

    Science.gov (United States)

    Jilkova, Veronika; Picek, Tomas; Cajthaml, Tomas; Frouz, Jan

    2016-04-01

    Wood ant nests are known as hot spots of carbon dioxide (CO2) production and are also thought to affect methane (CH4) flux. Stable high temperatures are maintained in ant nests even in cold environments. Here we focused on quantification of CO2 and CH4 flux in wood ant nests, contribution of ants and microbes to CO2 production, properties of nest material that affect CO2 production and the role of ants and microbes in the maintenance of nest temperature. The research was conducted in temperate and boreal forests inhabited by wood ants (Formica s. str.). Gas fluxes were measured either by an infrared gas analyser or a static chamber technique. Ants and nest materials were also incubated in a laboratory. Material properties potentially influencing CO2 flux, such as moisture, nutrient content or temperature were determined. According to the results, CH4 oxidation was lower in wood ant nests than in the surrounding forest soil suggesting that some characteristics of ant nests hinder CH4 oxidation or promote CH4 production. These characteristics were mainly available carbon and nitrogen contents. Wood ant nests clearly are hot spots of CO2 production in temperate forests originating mainly from ant and also from microbial metabolism. Most important properties positively affecting CO2 production were found to be moisture, nutrient content and temperature. Nest temperature is maintained by ant and microbial metabolism; nests from colder environments produce more metabolic heat to maintain similar temperature as nests from warmer environments. In conclusion, as the abundance of wood ant nests in some forests can be very high, ant nests may largely increase heterogeneity in greenhouse gas fluxes in forest ecosystems.

  17. Strategic Placement of Treatments (SPOTS): Maximizing the Effectiveness of Fuel and Vegetation Treatments on Problem Fire Behavior and Effects

    Science.gov (United States)

    Diane M. Gercke; Susan A. Stewart

    2006-01-01

    In 2005, eight U.S. Forest Service and Bureau of Land Management interdisciplinary teams participated in a test of strategic placement of treatments (SPOTS) techniques to maximize the effectiveness of fuel treatments in reducing problem fire behavior, adverse fire effects, and suppression costs. This interagency approach to standardizing the assessment of risks and...

  18. Qualitative research ethics on the spot

    DEFF Research Database (Denmark)

    Sørensen, Nelli Øvre; Øye, Christine; Glasdam, Stinne

    2015-01-01

    , the article explores and discusses research ethical dilemmas. Objectives and ethical considerations: First, and especially, the article addresses the challenges for gatekeepers who influence the informant’s decisions to participate in research. Second, the article addresses the challenges in following...... research ethical guidelines related to informed consent and doing no harm. Third, the article argues for the importance of having research ethical guidelines and review boards to question and discuss the possible ethical dilemmas that occur in qualitative research. Discussion and conclusion: Research...... ethics must be understood in qualitative research as relational, situational, and emerging. That is, that focus on ethical issues and dilemmas has to be paid attention on the spot and not only at the desktop....

  19. Dispersion of hot spots in steam generators

    International Nuclear Information System (INIS)

    Achenbach, E.J.

    1988-01-01

    The streamwise development of hot spots in a helical type heat exchanger has been treated experimentally and theoretically as well. Velocity profiles across the bundle have been measured varying the Reynolds number, Re, from 10 3 to 1.35 x 10 5 . Pressurized air or helium have been applied as coolant. In an additional series of tests the length scale parameter of the turbulence structure has been determined. It is correlated with the turbulent Peclet number, Pe t , which occurs in the basic equation as an unknown parameter. Its value was found to be independent of Re (Pe t = 8.2). Introducing this value leads to a good agreement of theoretical and experimental results. (author)

  20. Auroral bright spot sequence near 14 MLT

    International Nuclear Information System (INIS)

    Sandholt, P.E.; Lybekk, B.

    1990-08-01

    Optical observations of a dayside auroral brightening sequence, by means of all-sky TV cameras and meridian scanning photometers, have been combined with EISCAT ion drift observations within the same invariant latitude - MLT sector. The reported events, covering a 35 min interval around 14 MLT, are embedded within a longer period of similar auroral activity between 0830 (1200 MLT) and 1300 UT (1600 MLT). These observations are discussed in relation to recent models of boundary layer plasma dynamics and the associated magnetosphere-ionosphere coupling. The ionospheric events may correspond to large-scale wavelike motions of the low-latitude boundary layer. Based on this interpretation the observed spot size, speed and repetition period (∼ 10 min) give a wavelenght ∼ 900 km in the present case. The events can also be explained as ionospheric signatures of newly opened flux tubes associated with reconnection bursts at the magnetopause near 1400 MLT. 46 refs., 11 figs

  1. A microsatellite platform for hot spot detection

    Energy Technology Data Exchange (ETDEWEB)

    Walter, I.; Briess, K.; Baerwald, W.; Lorenz, E.; Skrbek, W.; Schrandt, F. [DLR, Berlin (Germany). Inst. of Space Sensor Technology & Planetary Exploration

    2005-01-01

    The main payload of the BIRD micro-satellite is the newly developed hot spot recognition system. It's a dual-channel instrument for middle and thermal infrared imagery based on cooled MCT line detectors. The miniaturisation by integrated detector/cooler assemblies provides a highly efficient design. Since the launch in October 2001 from SHAR/India the BIRD payload, claiming 30% of the BIRD mass of 92 kg, is fully operational. Among others forest fires (Australia), volcanoes (Etna, Chile) and burning coal mines (China) have been detected and their parameters like size, temperature and energy release could be determined. As the status of the payload system is satisfactorily it has a potential to be applied in new missions with the help of modern detector technology.

  2. Characterizing and Estimating Fungal Disease Severity of Rice Brown Spot with Hyperspectral Reflectance Data

    Directory of Open Access Journals (Sweden)

    Zhan-yu LIU

    2008-09-01

    Full Text Available Large-scale farming of agriculture crops requires real-time detection of disease for field pest management. Hyperspectral remote sensing data generally have high spectral resolution, which could be very useful for detecting disease stress in green vegetation at the leaf and canopy levels. In this study, hyperspectral reflectances of rice in the laboratory and field were measured to characterize the spectral regions and wavebands, which were the most sensitive to rice brown spot infected by Bipolaris oryzae (Helminthosporium oryzae Breda. de Hann. Leaf reflectance increased at the ranges of 450 to 500 nm and 630 to 680 nm with the increasing percentage of infected leaf surface, and decreased at the ranges of 520 to 580 nm, 760 to 790 nm, 1550 to 1750 nm, and 2080 to 2350 nm with the increasing percentage of infected leaf surface respectively. The sensitivity analysis and derivative technique were used to select the sensitive wavebands for the detection of rice brown spot infected by B. oryzae. Ratios of rice leaf reflectance were evaluated as indicators of brown spot. R669/R746 (the reflectance at 669 nm divided by the reflectance at 746 nm, the following ratios may be deduced by analogy, R702/R718, R692/R530, R692/R732, R535/R746, R521/R718, and R569/R718 increased significantly as the incidence of rice brown spot increased regardless of whether it's at the leaf or canopy level. R702/R718, R692/R530, R692/R732 were the best three ratios for estimating the disease severity of rice brown spot at the leaf and canopy levels. This result not only confirms the capability of hyperspectral remote sensing data in characterizing crop disease for precision pest management in the real world, but also testifies that the ratios of crop reflectance is a useful method to estimate crop disease severity.

  3. Kekuatan Geser dan Pola Patahan Loop Space Maintainer yang Dibuat dengan Teknik Spot Welding Elektrik

    Directory of Open Access Journals (Sweden)

    Elin Karlina

    2015-10-01

    Full Text Available The aim of this research was to study the effect of spot variations on shear strength of spot welds in an electric loop space maintainer. Stainless steel wire of 0.8 mm diameter and nickel chromium crwon for lower second molar of temporary teeth were used. A loop 1 cm wide, made of 3.5 cm stainless steel wire, was welded with 3 dots on the crown using an electric spot welder. Each dot for each group took different spot variations from 1 X – 4 X. A loop space maintainer made with the usual materials and techniques as applied at the IKGA FKG UI Clinic was used as a control, with a torch as heat source. Ten specimens each were prepared for shear testing and three spesimens each for metallography. Universal testing machine was used for shear strength testing at a crosshead speed of 0.5 mm/min, and SEM/EDS was used for metallography and fractography. The data were statistically analyzed with one-way ANOVA at p = 0.05, and Tukey post hoc test. The results show that the shear strength of the welded loop space maintainer was higher than that of a soldered loop space maintainer, although the difference was not statistically significant with spot variation 1 X. SEM/EDS analysis suggests that a new alloy forms at the contact area of welded and soldered loop space maintainer. Fractography of the joints suggests that welds are better than soldered joints, with higher ductility and toughness, as can be seen from the dimpled pattern of the welded joint and cleavage patterns in the control joints. In conclusion, the loop space maintainer is better made by welding than by soldering.

  4. Multi-image acquisition-based distance sensor using agile laser spot beam.

    Science.gov (United States)

    Riza, Nabeel A; Amin, M Junaid

    2014-09-01

    We present a novel laser-based distance measurement technique that uses multiple-image-based spatial processing to enable distance measurements. Compared with the first-generation distance sensor using spatial processing, the modified sensor is no longer hindered by the classic Rayleigh axial resolution limit for the propagating laser beam at its minimum beam waist location. The proposed high-resolution distance sensor design uses an electronically controlled variable focus lens (ECVFL) in combination with an optical imaging device, such as a charged-coupled device (CCD), to produce and capture different laser spot size images on a target with these beam spot sizes different from the minimal spot size possible at this target distance. By exploiting the unique relationship of the target located spot sizes with the varying ECVFL focal length for each target distance, the proposed distance sensor can compute the target distance with a distance measurement resolution better than the axial resolution via the Rayleigh resolution criterion. Using a 30 mW 633 nm He-Ne laser coupled with an electromagnetically actuated liquid ECVFL, along with a 20 cm focal length bias lens, and using five spot images captured per target position by a CCD-based Nikon camera, a proof-of-concept proposed distance sensor is successfully implemented in the laboratory over target ranges from 10 to 100 cm with a demonstrated sub-cm axial resolution, which is better than the axial Rayleigh resolution limit at these target distances. Applications for the proposed potentially cost-effective distance sensor are diverse and include industrial inspection and measurement and 3D object shape mapping and imaging.

  5. [The spotted sterile male--a new mutation of dominant spotting on the mouse chromosome 5].

    Science.gov (United States)

    Blandova, Z K; Vakhrusheva, M P; Malashenko, A M; Osipov, V V

    1986-06-01

    Spotted sterile male - a new mutation in mice is described (tentative symbol Ssm). White spotting on the belly, legs and tail as well as sterility in heterozygous males Ssm/+ of the B10.M strain are caused by autosomal semidominant gene Ssm. The gene is localized on the 5 chromosome: the frequency of recombination between Ssm and go is 13.6 +/- 1.6%; Ssm is closely linked to Wv. The diheterozygotes Ssm+/+Wv are darkeyed white sterile mice. The deficiency of spermatogenic epithelium cells, emptyness of seminiferous tubules as well as interstitial tissue overgrowing occurred in the testis in sterile males Ssm/+ of B10.M. The fertile hybrid males Ssm/+ are obtained in outcrossing of females Ssm/+ of B10.M with males of YT/Y, CBA/CaY, DBA/2JY, A.CA/Y strains.

  6. State of the art in the estimation of energy prices in the spot market

    International Nuclear Information System (INIS)

    Botero B, Sergio; Cano C, Jovan A

    2007-01-01

    Since the start energy markets deregulation in the world, several spot market (short term) price prediction methods have been developed? this article identifies and compares the main methods of prediction used in Colombia and other international markets. With this review it is possible to determine the state of the knowledge in the specific subject and then to look for the development of new forecasting techniques that can contribute to the solution of this problem. The prediction horizon is something that must be taken into account in the review of the several techniques, given that both the magnitude of the final model of estimation, and the time series treatment type, depend on this horizon.

  7. Fatigue crack growth retardation in spot heated mild steel sheet

    Indian Academy of Sciences (India)

    Unknown

    Abstract. A fatigue crack can be effectively retarded by heating a spot near the crack tip under nil remote stress condition. The subcritical spot heating at a proper position modifies the crack growth behaviour in a way, more or less, similar to specimen subjected to overload spike. It is observed that the extent of crack.

  8. Fatigue crack growth retardation in spot heated mild steel sheet

    Indian Academy of Sciences (India)

    Spot heating; overloading; fatigue crack growth retardation; residual stress; delay cycles. ... It is observed that the extent of crack growth retardation increases with increasing level of overload as well as with increasing spot temperature. It is also ... Manuscript received: 29 November 2001; Manuscript revised: 24 June 2002 ...

  9. Inheritance of resistance to angular leaf spot in yellow beans ...

    African Journals Online (AJOL)

    Angular leaf spot (Phaeoisariopsis griseola (Sacc) is an important disease of common bean (Phaseolus vulgaris L.) in most parts of Africa, causing yield losses of 40-80%. This study was carried out to determine the inheritance of resistance to angular leaf spot in yellow beans. Biparental crosses were done between ...

  10. Spatial Analysis of Accident Spots Using Weighted Severity Index ...

    African Journals Online (AJOL)

    Weighted Severity Index (WSI) was created based on these factors/drivers. Also, Density-based Clustering for Traffic Accident Risk (DBCTAR) was carried out to assist in ascertaining the distribution of Black Spots Severity (BSS). Results obtained include: shortestpath analysis, service area analysis, accident spot severity ...

  11. Fatigue crack growth retardation in spot heated mild steel sheet

    Indian Academy of Sciences (India)

    A fatigue crack can be effectively retarded by heating a spot near the crack tip under nil remote stress condition. The subcritical spot heating at a proper position modifies the crack growth behaviour in a way, more or less, similar to specimen subjected to overload spike. It is observed that the extent of crack growth retardation ...

  12. Identification of electricity spot models by using convolution particle filter

    NARCIS (Netherlands)

    Aihara, ShinIchi; Bagchi, Arunabha; Imreizeeq, E.S.N.

    2011-01-01

    We consider a slight perturbation of the Schwartz-Smith model for the electricity futures prices and the resulting modied spot model. Using the martingale property of the modied price under the risk neutral measure, we derive the arbitrage free model for the spot and futures prices. As the futures

  13. Food habits of Mexican Spotted Owls in Arizona

    Science.gov (United States)

    Joseph L. Ganey

    1992-01-01

    The Spotted Owl (Strix occidentalis) is most common in mature and old-growth coniferous forests throughout much of its range (Forsman et al. 1984, Laymon 1988, Ganey and Balda 1989a, Thomas et al. 1990). Proximate factors underlying habitat selection in Spotted Owls are understood poorly. Abundance and availability of food, however, may be a key...

  14. Spotted owl roost and nest site selection in northwestern California

    Science.gov (United States)

    J.A. Blakesley; A.B. Franklin; R.J. Gutierrez

    1992-01-01

    We directly observed roost and nest site selection in a population of northern spotted owls (Strix occidentalis caurina) in northwestern California during 1985-89. Because of potential biases caused by use of radio telemetry in previous studies, we examined habitat use relative to habitat availability at a level not previously reported for spotted...

  15. Different methods of fluoride delivery in prevention of white spot ...

    African Journals Online (AJOL)

    Orthodontic patients on fixed appliances are at an increased risk of developing white spot lesions which can progress to frank cavitations. Fluoride application in different forms has been shown to be effective in the reduction of formation of white spot lesions. The aim of this short communication is to discuss different ...

  16. Nucleus geometry and mechanical properties of resistance spot ...

    Indian Academy of Sciences (India)

    Abstract. In this study, mechanical properties of resistance spot welding of DP450 and DP600, galvanized and ungalvanized automotive sheets have been investigated. The specimens have been joined by resistance spot welding at different weld currents and times. Welded specimens have been examined for their ...

  17. Estimates of age, growth and mortality of spotted catfish, Arius ...

    African Journals Online (AJOL)

    Spotted catfish is a benthic species that can be found abundantly off the coast of Yunlin in southwestern Taiwan. Its biological parameters are little known. In this study, life history parameters of this species were estimated using samples caught by bottom trawling. The spotted catfish was the major bycatch species which ...

  18. Laser Beam Caustic Measurement with Focal Spot Analyser

    DEFF Research Database (Denmark)

    Olsen, Flemming Ove; Gong, Hui; Bagger, Claus

    2005-01-01

    In industrial applications of high power CO2-lasers the caustic characteristics of the laser beam have great effects on the performance of the lasers. A welldefined high intense focused spot is essential for reliable production results. This paper presents a focal spot analyser that is developed...... for measuring the beam profiles of focused high power CO2-lasers....

  19. Treatment of White Spot Lesions with Icon (Resin Infiltration)

    Science.gov (United States)

    2017-03-23

    FROM: 59 MDW/SGVU SUBJECT: Professional Presentation Approval 8 MAR2017 1. Your paper, entitled T reatment of White Spot Lesions with Icon ( Resin ... Resin Infiltration) 6. TITLE OF MATERIAL TO BE PUBLISHED OR PRESENTED: Treatment of White Spot lesions with Icon ( Resin In filtration) 7. FUNDING

  20. 7 CFR 28.425 - Low Middling Spotted Color.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 2 2010-01-01 2010-01-01 false Low Middling Spotted Color. 28.425 Section 28.425 Agriculture Regulations of the Department of Agriculture AGRICULTURAL MARKETING SERVICE (Standards... Color. Low Middling Spotted Color is color which is within the range represented by a set of samples in...

  1. 7 CFR 28.422 - Strict Middling Spotted Color.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 2 2010-01-01 2010-01-01 false Strict Middling Spotted Color. 28.422 Section 28.422 Agriculture Regulations of the Department of Agriculture AGRICULTURAL MARKETING SERVICE (Standards... Color. Strict Middling Spotted Color is color which is within the range represented by a set of samples...

  2. Characterizing and identifying black spot resistance genes in polyploid roses

    Science.gov (United States)

    The ornamental quality of outdoor grown roses (Rosa hybrida) is under constant threat from foliar diseases, such as black spot caused by Diplocarpon rosae. Fungicides are primarily used to manage black spot; however, there is a high consumer demand for disease resistant roses which eliminate the nee...

  3. Alternaria leaf spot of sugar beet: factors associated with risk

    Science.gov (United States)

    Recently, increased incidence and severity of Alternaria leaf spot has been observed in Michigan and other growing regions. In the past, Alternaria leaf spot in sugar beet has been a minor foliar disease issue in the United States and management of this disease usually has not been required. If seve...

  4. inheritance of resistance to angular leaf spot in yellow beans ...

    African Journals Online (AJOL)

    Prof. Adipala Ekwamu

    Susceptible. II -indeterminate erect; III -indeterminate semi-prostate; ALS = Angular leaf spot. Isolation of Phaeoisariopsis griseola and plant inoculation. Isolation of angular leaf spot was made from lesions of naturally infected bean leaves showing fungal sporulation. In the case of non-sporulating lesions, the fungus was.

  5. Parameter estimation of electricity spot models from futures prices

    NARCIS (Netherlands)

    Aihara, ShinIchi; Bagchi, Arunabha; Imreizeeq, E.S.N.; Walter, E.

    We consider a slight perturbation of the Schwartz-Smith model for the electricity futures prices and the resulting modified spot model. Using the martingale property of the modified price under the risk neutral measure, we derive the arbitrage free model for the spot and futures prices. We estimate

  6. Firebrands and spotting ignition in large-scale fires

    Science.gov (United States)

    Eunmo Koo; Patrick J. Pagni; David R. Weise; John P. Woycheese

    2010-01-01

    Spotting ignition by lofted firebrands is a significant mechanism of fire spread, as observed in many largescale fires. The role of firebrands in fire propagation and the important parameters involved in spot fire development are studied. Historical large-scale fires, including wind-driven urban and wildland conflagrations and post-earthquake fires are given as...

  7. The Effect of Contact Angle on Dynamics of Dry Spots Spreading in a Horizontal Layer of Liquid at Local Heating

    Directory of Open Access Journals (Sweden)

    Zaitsev D.V.

    2015-01-01

    Full Text Available The effect of equilibrium contact angle on dynamics of dry spot spreading at disruption of a horizontal water layer heated locally from the substrate was studied using the high-speed Schlieren technique. Different methods of working surface processing were applied; this allowed variations of the equilibrium contact angle from 27±6° to 74±9° without a change in thermal properties of the system. It is found out that substrate wettability significantly affects the propagation velocity of dry spot and its final size. It is also found out that the velocity of contact line propagation is higher in the areas of substrate with a higher temperature.

  8. Optimization of resistance spot welding parameters for microalloyed steel sheets

    Science.gov (United States)

    Viňáš, Ján; Kaščák, Ľuboš; Greš, Miroslav

    2016-11-01

    The paper presents the results of resistance spot welding of hot-dip galvanized microalloyed steel sheets used in car body production. The spot welds were made with various welding currents and welding time values, but with a constant pressing force of welding electrodes. The welding current and welding time are the dominant characteristics in spot welding that affect the quality of spot welds, as well as their dimensions and load-bearing capacity. The load-bearing capacity of welded joints was evaluated by tensile test according to STN 05 1122 standard and dimensions and inner defects were evaluated by metallographic analysis by light optical microscope. Thewelding parameters of investigated microalloyed steel sheets were optimized for resistance spot welding on the pneumatic welding machine BPK 20.

  9. Reliability of copper based alloys for electric resistance spot welding

    International Nuclear Information System (INIS)

    Jovanovicj, M.; Mihajlovicj, A.; Sherbedzhija, B.

    1977-01-01

    Durability of copper based alloys (B-5 and B-6) for electric resistance spot-welding was examined. The total amount of Be, Ni and Zr was up to 2 and 1 wt.% respectively. Good durability and satisfactory quality of welded spots were obtained in previous laboratory experiments carried out on the fixed spot-welding machine of an industrial type (only B-5 alloy was examined). Electrodes made of both B-5 and B-6 alloy were tested on spot-welding grips and fixed spot-welding machines in Tvornica automobila Sarajevo (TAS). The obtained results suggest that the durability of electrodes made of B-5 and B-6 alloys is more than twice better than of that used in TAS

  10. Estimulação cerebral contínua (DBS talâmica para controle do tremor Deep brain stimulation of VIM thalamic nucleus for tremor control

    Directory of Open Access Journals (Sweden)

    José Augusto Nasser

    2002-06-01

    Full Text Available OBJETIVO: Apresentamos resultados da estimulação contínua do núcleo ventral intermédio (VIM talâmico para o controle do tremor. MÉTODO: Quatro pacientes foram selecionados no período de outubro de 1999 a janeiro de 2001 com tremor incapacitante refratário à farmacoterapia. Dois pacientes apresentavam tremor essencial (TE bilateral e 2 pacientes tremor de repouso por doença de Parkinson (DP, um à direita e outro à esquerda. Após avaliação sistemática, foram submetidos ao implante de eletrodo talâmico, modelo DBS 3387(Medtronic, para estimulação cerebral profunda (ECP com alta frequência, sendo este bilateral nos casos de TE e unilateral nos casos com tremor por DP. RESULTADOS: Os pacientes tiveram seu seguimente clínico até o presente, com média de 12 meses, sendo observada a eficácia da estimulação do núcleo VIM no controle dos disparos das células do tremor. As complicações temporárias do tipo parestesias, disartrias e discreto aumento do tônus foram revertidas após o ajuste dos parâmetros de estimulação. CONCLUSÃO: Os resultados confirmam os achados da literatura, de que a estimulação talâmica é excelente opção terapêutica no tratamento do tremor, havendo possibilidade de estimulação talâmica bilateral simultânea com segurança.PURPOSE: We present our results in 4 patients with tremor, in whom electrodes (uni and bilateral for Deep Brain Stimulation (DBS were implanted in the ventral intermediate nucleus (VIM of the thalamus. METHOD: Four patients with disabling tremor, with drug-resistant spite of optimum therapeutic trials with poor response were referred to do surgery. Two patients had bilateral essential tremor. These patients were implanted with electrodes for DBS 3387 (Medtronic. Two patients had unilateral parkinsonian tremor and they received unilateral implantation of model 3387 DBS. RESULTS: All four patients showed relieve of the tremor symptoms with significant tremor control seen at

  11. Meteorology of Jupiter's Equatorial Hot Spots and Plumes from Cassini

    Science.gov (United States)

    Choi, David Sanghun; Showman, Adam P.; Vasavada, Ashwin R.; Simon-Miller, Amy A.

    2013-01-01

    We present an updated analysis of Jupiter's equatorial meteorology from Cassini observations. For two months preceding the spacecraft's closest approach, the Imaging Science Subsystem (ISS) onboard regularly imaged the atmosphere. We created time-lapse movies from this period in order to analyze the dynamics of equatorial hot spots and their interactions with adjacent latitudes. Hot spots are relatively cloud-free regions that emit strongly at 5 lm; improved knowledge of these features is crucial for fully understanding Galileo probe measurements taken during its descent through one. Hot spots are quasistable, rectangular dark areas on visible-wavelength images, with defined eastern edges that sharply contrast with surrounding clouds, but diffuse western edges serving as nebulous boundaries with adjacent equatorial plumes. Hot spots exhibit significant variations in size and shape over timescales of days and weeks. Some of these changes correspond with passing vortex systems from adjacent latitudes interacting with hot spots. Strong anticyclonic gyres present to the south and southeast of the dark areas appear to circulate into hot spots. Impressive, bright white plumes occupy spaces in between hot spots. Compact cirrus-like 'scooter' clouds flow rapidly through the plumes before disappearing within the dark areas. These clouds travel at 150-200 m/s, much faster than the 100 m/s hot spot and plume drift speed. This raises the possibility that the scooter clouds may be more illustrative of the actual jet stream speed at these latitudes. Most previously published zonal wind profiles represent the drift speed of the hot spots at their latitude from pattern matching of the entire longitudinal image strip. If a downward branch of an equatorially-trapped Rossby wave controls the overall appearance of hot spots, however, the westward phase velocity of the wave leads to underestimates of the true jet stream speed.

  12. Selected immobilization of individual nanoparticles by spot-exposure electron-beam-induced deposition

    Energy Technology Data Exchange (ETDEWEB)

    Burbridge, Daniel J; Crampin, Simon; Gordeev, Sergey N [Department of Physics, University of Bath, Claverton Down, Bath BA2 7AY (United Kingdom); Viau, Guillaume [Departement de Genie Physique, INSA de Toulouse, 135 avenue de Rangueil, 31077 Toulouse Cedex 4 (France)

    2010-01-29

    The use of spot-exposure electron-beam-induced deposition (EBID) to immobilize targeted nanoparticles on a substrate is demonstrated, and investigated using experiment and simulation. Nanoparticles are secured in place through the build-up of carbonaceous material that forms in the region between a particle and substrate when an energetic electron beam is focused onto the particle and projected through to the substrate. Material build-up directly affects the strength of adhesion to the surface, and can be controlled through electron dosage and beam energy. By selectively immobilizing specific particles within surface agglomerations and removing the excess, we illustrate the potential for spot-exposure EBID as a new technique for nanofabrication.

  13. Exploring User Acceptance Of Free Wireless Fidelity Public Hot Spots: An Emperical Study

    Directory of Open Access Journals (Sweden)

    Ezejiofo Patrick Udeh

    2008-01-01

    Full Text Available Research regarding commercial and free wireless fidelity (Wi-Fi public hot spots acceptance and adoption is sketchy. Therefore, it has become imperative to understand the critical factors that affect their acceptance. The focus of this study is free Wi-Fi public hot spot users, with the objective to better understand their user acceptance. In doing so, this study integrated two well-established initial acceptance models, specifically, the technology acceptance model and the diffusion of innovation theory. This study was conducted using an on-line survey that collected data from 129 users. It uses the Partial Least Square (PLS technique to examine the relationship between variables. The results indicate that each critical factor has direct or indirect positive effects on current use and/or future use intention, which confirmed the majority of the proposed hypotheses. Relative advantage emerged as the only construct with a direct positive effect on both current use and future use intentions.

  14. Well log and seismic application in delineating CBM sweet spot in Berau Basin, East Kalimantan

    Science.gov (United States)

    Hamdani, Ahmad Helman; Hamdiana, Diana Putri; Ramadhan, Welly Ahmad

    2013-09-01

    The study area is situated in the northern part of Berau Basin Northeast of Kalimantan. In the area Sajau Formation is the main coal bearing formation. The Sajau Coal were range from Lignite to sub bituminous, low ash content, and low to high cleated coal. Different with the conventional reservoir, coalbed methane reservoirs have sweet spot that are a function of structural/cleat and stratigraphy of the coal seam. The seismic data provides excellent image of faults and stratigraphy of coal seams are very much essential in CBM exploration as delineating the CBM sweet spot. Well log and acoustic impedance inversion can be applied in such a way to provide added insight to the coal distribution and cleat directions in coalbed-methane reservoirs. In this technique the property of acoustic impedance is of much importance in identifying different rock formations, which are associated with coal, and it has been successfully implemented.

  15. Predicting favorable conditions for early leaf spot of peanut using output from the Weather Research and Forecasting (WRF) model.

    Science.gov (United States)

    Olatinwo, Rabiu O; Prabha, Thara V; Paz, Joel O; Hoogenboom, Gerrit

    2012-03-01

    Early leaf spot of peanut (Arachis hypogaea L.), a disease caused by Cercospora arachidicola S. Hori, is responsible for an annual crop loss of several million dollars in the southeastern United States alone. The development of early leaf spot on peanut and subsequent spread of the spores of C. arachidicola relies on favorable weather conditions. Accurate spatio-temporal weather information is crucial for monitoring the progression of favorable conditions and determining the potential threat of the disease. Therefore, the development of a prediction model for mitigating the risk of early leaf spot in peanut production is important. The specific objective of this study was to demonstrate the application of the high-resolution Weather Research and Forecasting (WRF) model for management of early leaf spot in peanut. We coupled high-resolution weather output of the WRF, i.e. relative humidity and temperature, with the Oklahoma peanut leaf spot advisory model in predicting favorable conditions for early leaf spot infection over Georgia in 2007. Results showed a more favorable infection condition in the southeastern coastline of Georgia where the infection threshold were met sooner compared to the southwestern and central part of Georgia where the disease risk was lower. A newly introduced infection threat index indicates that the leaf spot threat threshold was met sooner at Alma, GA, compared to Tifton and Cordele, GA. The short-term prediction of weather parameters and their use in the management of peanut diseases is a viable and promising technique, which could help growers make accurate management decisions, and lower disease impact through optimum timing of fungicide applications.

  16. Wood ant nests as hot spots of carbon dioxide production and cold spots of methane oxidation in temperate forests

    Czech Academy of Sciences Publication Activity Database

    Jílková, Veronika; Picek, T.; Cajthaml, Tomáš; Frouz, Jan

    2016-01-01

    Roč. 18, April (2016), EGU2016-4634 ISSN 1607-7962. [European Geosciences Union General Assembly 2016. 17.04.2016-22.04.2016, Vienna] Institutional support: RVO:60077344 ; RVO:61388971 Keywords : wood ant nests * hot spots of carbon dioxide production * cold spots of methane oxidation * temperate forests Subject RIV: DF - Soil Science

  17. Online resistance spot weld NDE using infrared thermography

    Science.gov (United States)

    Chen, Jian; Feng, Zhili

    2017-04-01

    A new online resistance spot weld non-destructive evaluation (NDE) technique based on infrared (IR) thermography has been developed. It is capable of both real-time online (during welding) and post-weld online/offline (after welding) inspections. The system mainly consists of an IR camera and a computer program with proprietary thermal imaging analysis algorithms integrated into existing production lines. For real-time inspection, the heat flow generated from the welding process (with temperature exceeding 1000°C) is monitored by the IR camera. For post-weld inspection, a novel auxiliary heating device is applied to locally heat the weld region, resulting in temperature changes on the order of 10°C, and the transmitted heat flow is monitored. Unlike the conventional IR NDE method that requires surface coating to reduce the influence of unknown emissivity, the new method can be applied on as-is bare metal surface thanks to the unique "thermal signatures" extracted from infrared thermal images, which positively correlates to weld quality with a high degree of confidence. The new method can be used to reliably detect weld size, surface indents and defects such as cold weld with sufficient accuracy for welds made from various combinations of materials, thickness, stack-up configuration, surface coating conditions and welding conditions.

  18. Deep insight into white spot syndrome virus vaccines: A review

    Directory of Open Access Journals (Sweden)

    MA Badhul Haq

    2012-02-01

    Full Text Available White spot syndrome virus (WSSV, the causative virus of the disease, is found in most shrimp farming areas of the world, where it causes large economic losses to the shrimp farming industry. The potentially fatal virus has been found to be a threat not only to all shrimp species, but also to other marine and freshwater crustaceans, such as crab and crayfish. To date, no effective prophylactic treatment measures are available for viral infections in shrimp and other crustaceans. Due to current aquaculture practices and the broad host range of WSSV, intervention strategies including vaccination against this virus would be pivotal to save and protect shrimp farming. Several achievements have been attained in the search of novel vaccines for WSSV. DNA vaccination, recombinant vaccines, oral vaccination techniques and gene therapy are some of the thrust areas of focus for scientists and researchers. This review article highlights the recent trends in the development of WSSV vaccines either as DNA vaccines or recombinant vaccines and their functioning strategies as suggested by the researchers worldwide.

  19. Electrocardiographic exam in female spotted pacas (Cuniculus paca

    Directory of Open Access Journals (Sweden)

    Ricardo A.R. Uscategui

    2016-06-01

    Full Text Available Abstract: Considering the limited physiological information available on neotropical rodents and the importance of this information for pathophysiological and conservation studies of these species, the aim of this study was to evaluate the cardiac electric physiology of healthy captivity spotted pacas (Cuniculus paca under chemical restraint, due to wild nature of these animals. Eleven adult female pacas were evaluated by blood count and biochemical dosage to rule out any associate disease. Each animal was evaluated in three periods every 15 days. After chemical restraint with intramuscular midazolam 0.5mg/kg and ketamine 25mg/kg, animals were subjected to a computerized electrocardiogram, where bipolar (DI, DII and DIII and augmented unipolar leads (aVR, aVL, aVF were obtained. Descriptive statistics were calculated for each parameter and built the confidence interval (CI at significance level of 95%. The electrocardiographic examination was performed without difficult. ECG tracing in DII represents a QRS complex with positive polarity, preceded by a P wave of the same polarity and proceeded by T wave of variable polarity. Heart rate mean was 150±17 bpm, and cardiac electrical axis 33.4±21.9°. All animals showed sinusal rhythm. The ECG recording technique associated with chemical restraint was well tolerated, allowing quick acquisition of reliable ECG tracings with high repeatability, which produced sufficient results to determine the heart rhythm and suggest measures of ECG complexes duration and amplitude.

  20. Review: magnetically assisted resistance spot welding

    Energy Technology Data Exchange (ETDEWEB)

    Li, Y. B. [Shanghai Jiao Tong Univ., Shanghai (China); Li, D. L. [Shanghai Jiao Tong Univ., Shanghai (China); Lin, Z. Q. [Shanghai Jiao Tong Univ., Shanghai (China); David, Stan A. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Feng, Zhili [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Tang, Wei [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)

    2016-02-25

    Currently, the use of advanced high strength steels (AHSSs) is the most cost effective means of reducing vehicle body weight and maintaining structural integrity at the same time. However, AHSSs present a big challenge to the traditional resistance spot welding (RSW) widely applied in automotive industries because the rapid heating and cooling procedures during RSW produce hardened weld microstructures, which lower the ductility and fatigue properties of welded joints and raise the probability of interfacial failure under external loads. Changing process parameters or post-weld heat treatment may reduce the weld brittleness, but those traditional quality control methods also increase energy consumption and prolong cycle time. In recent years, a magnetically assisted RSW (MA-RSW) method was proposed, in which an externally applied magnetic field would interact with the conduction current to produce a Lorentz force that would affect weld nugget formation. This paper is a review of an experimental MA-RSW platform, the mode of the external magnetic field and the mechanism that controls nugget shape, weld microstructures and joint performance. In conclusion, the advantages of the MA-RSW method in improving the weldability of AHSSs are given, a recent application of the MA-RSW process to light metals is described and the outlook for the MA-RSW process is presented.

  1. Turbulent Spot Pressure Fluctuation Wave Packet Model

    Energy Technology Data Exchange (ETDEWEB)

    Dechant, Lawrence J. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

    2017-05-01

    Wave packet analysis provides a connection between linear small disturbance theory and subsequent nonlinear turbulent spot flow behavior. The traditional association between linear stability analysis and nonlinear wave form is developed via the method of stationary phase whereby asymptotic (simplified) mean flow solutions are used to estimate dispersion behavior and stationary phase approximation are used to invert the associated Fourier transform. The resulting process typically requires nonlinear algebraic equations inversions that can be best performed numerically, which partially mitigates the value of the approximation as compared to a more complete, e.g. DNS or linear/nonlinear adjoint methods. To obtain a simpler, closed-form analytical result, the complete packet solution is modeled via approximate amplitude (linear convected kinematic wave initial value problem) and local sinusoidal (wave equation) expressions. Significantly, the initial value for the kinematic wave transport expression follows from a separable variable coefficient approximation to the linearized pressure fluctuation Poisson expression. The resulting amplitude solution, while approximate in nature, nonetheless, appears to mimic many of the global features, e.g. transitional flow intermittency and pressure fluctuation magnitude behavior. A low wave number wave packet models also recover meaningful auto-correlation and low frequency spectral behaviors.

  2. Mediterranean spotted fever in southeastern Romania.

    Science.gov (United States)

    Pitigoi, Daniela; Olaru, Ioana D; Badescu, Daniela; Rafila, Alexandru; Arama, Victoria; Hristea, Adriana

    2013-01-01

    Although cases of Mediterranean spotted fever (MSF) have been reported for decades in southeastern Romania, there are few published data. We retrospectively studied 339 patients, diagnosed with MSF at the National Institute of Infectious Diseases "Prof. Dr. Matei Bals" between 2000 and 2011, in order to raise awareness about MSF in certain regions of Romania. According to the Raoult diagnostic criteria 171 (50.4%) had a score >25 points. Mean age was 52.5 years. One hundred and fifty-five (90.6%) patients were from Bucharest and the surrounding region. Almost all patients presented with fever (99.4%) and rash (98.2%), and 57.9% had evidence of a tick bite. There were no recorded deaths. Serologic diagnosis was made by indirect immunofluorescence assay. Of the 171 patients, serology results for R. conorii were available in 147. One hundred and twenty-three (83.7%) of them had a titer IgG ≥1:160 or a fourfold increase in titer in paired samples. MSF is endemic in southeastern Romania and should be considered in patients with fever and rash even in the absence of recognized tick exposure. Since the disease is prevalent in areas highly frequented by tourists, travel-associated MSF should be suspected in patients with characteristic symptoms returning from the endemic area.

  3. Mediterranean Spotted Fever in Southeastern Romania

    Directory of Open Access Journals (Sweden)

    Daniela Pitigoi

    2013-01-01

    Full Text Available Although cases of Mediterranean spotted fever (MSF have been reported for decades in southeastern Romania, there are few published data. We retrospectively studied 339 patients, diagnosed with MSF at the National Institute of Infectious Diseases “Prof. Dr. Matei Bals” between 2000 and 2011, in order to raise awareness about MSF in certain regions of Romania. According to the Raoult diagnostic criteria 171 (50.4% had a score >25 points. Mean age was 52.5 years. One hundred and fifty-five (90.6% patients were from Bucharest and the surrounding region. Almost all patients presented with fever (99.4% and rash (98.2%, and 57.9% had evidence of a tick bite. There were no recorded deaths. Serologic diagnosis was made by indirect immunofluorescence assay. Of the 171 patients, serology results for R. conorii were available in 147. One hundred and twenty-three (83.7% of them had a titer IgG ≥1 : 160 or a fourfold increase in titer in paired samples. MSF is endemic in southeastern Romania and should be considered in patients with fever and rash even in the absence of recognized tick exposure. Since the disease is prevalent in areas highly frequented by tourists, travel-associated MSF should be suspected in patients with characteristic symptoms returning from the endemic area.

  4. Feast or famine: 1992 spot market review

    Energy Technology Data Exchange (ETDEWEB)

    1993-01-01

    There was nothing temperate about the uranium spot market in 1992. It was a year of extremes. Demand took off at a brisk pace early in the year as utilities, enticed by low U3O8 prices and interest rates, stepped up their discretionary purchases. With the NUKEM price range sinking to an all-time low of US$6.75-7.70 in November 1991, utilities reckoned that prices had bottomed out and decided to buy and hold material. Indeed, the upper end of NUKEM's range remained below $8.00 per lb for much of the first half of 1992. The main cause of low prices was the flood of imports from the crumbling Soviet Union and its successor, the Commonwealth of Independent States [CIS]. The CIS republics quickly embraced a free-market philosophy to boost their faltering economies, and several hoped to use uranium as a source of badly-needed hard currency. But they were about to get a harsh introduction to capitalism. It came in the form of government intervention, in both the US and Europe. In May, the US Department of Commerce made its preliminary determination that the uranium-producing republics of the CIS were selling material in the US at less than fair market value. The antidumping case was eventually settled in October when the CIS republics [Russia, Ukraine, Uzbekistan, Kazakhstan, Tajikistan and Kyrgyzstan] signed suspension agreements subjecting CIS origin uranium to price and quantity quotas in the US.

  5. Finite Cosmology and a CMB Cold Spot

    Energy Technology Data Exchange (ETDEWEB)

    Adler, R.J.; /Stanford U., HEPL; Bjorken, J.D.; /SLAC; Overduin, J.M.; /Stanford U., HEPL

    2006-03-20

    The standard cosmological model posits a spatially flat universe of infinite extent. However, no observation, even in principle, could verify that the matter extends to infinity. In this work we model the universe as a finite spherical ball of dust and dark energy, and obtain a lower limit estimate of its mass and present size: the mass is at least 5 x 10{sup 23}M{sub {circle_dot}} and the present radius is at least 50 Gly. If we are not too far from the dust-ball edge we might expect to see a cold spot in the cosmic microwave background, and there might be suppression of the low multipoles in the angular power spectrum. Thus the model may be testable, at least in principle. We also obtain and discuss the geometry exterior to the dust ball; it is Schwarzschild-de Sitter with a naked singularity, and provides an interesting picture of cosmogenesis. Finally we briefly sketch how radiation and inflation eras may be incorporated into the model.

  6. Genome-wide DNA methylation profiling with MeDIP-seq using archived dried blood spots

    DEFF Research Database (Denmark)

    Staunstrup, Nicklas H; Starnawska, Anna; Nyegaard, Mette

    2016-01-01

    biobanks. However, availability of this biological material is highly limited as each DBS is made only from a few droplets of blood and storage conditions may be suboptimal for epigenetic studies. Furthermore, as relevant markers may reside outside gene bodies, epigenome-wide interrogation is needed....... RESULTS: Here we demonstrate, as a proof of principle, that genome-wide interrogation of the methylome based on methylated DNA immunoprecipitation coupled with next-generation sequencing (MeDIP-seq) is feasible using a single 3.2 mm DBS punch (60 ng DNA) from filter cards archived for up to 16 years...

  7. Comparison of outcomes between overlapping-spot and single-spot photodynamic therapy for circumscribed choroidal hemangioma

    Directory of Open Access Journals (Sweden)

    Zhao-An Su

    2014-02-01

    Full Text Available AIM:To compare the efficacy and safety of photodynamic therapy (PDT with overlapping multiple spots and single spot for treating circumscribed choroidal hemangioma.METHODS:Twenty-two patients (22 eyes with symptomatic circumscribed choroidal hemangioma received PDT treatment. Fourteen patients received overlapping spots (two to three spots PDT, whereas eight patients received single-spot PDT. Laser was used at 50J/cm2 for 83s in the overlapping-spot group and 50J/cm2 for 166s in the single-spot group. Clinical examination, funduscopy, fluorescein angiography, and ultrasonography were performed at baseline and after treatment.RESULTS:The mean follow-up time was 28.5±8.0 months in the overlapping-spot group and 27.0±5.0 months in the single-spot group. Nine patients (64.2% had their vision improved over two lines on the Snellen chart, and five patients showed stable visual acuity in the overlapping-spot group. The mean thickness of tumor decreased from 2.7±0.8mm to 1.2±0.9mm, and the mean greatest tumor linear dimension decreased from 7.4±1.5mm to 4.5±3.5mm after treatment. In the single-spot group, two patients (25% had their vision improved over two lines on the Snellen chart, and six patients had unchanged stable vision. The mean tumor thickness in this group decreased from 2.5±0.7mm to 1.4±1.0mm, and the mean greatest tumor linear dimension decreased from 7.2±1.3mm to 4.7±3.6mm. No significant differences in visual improvement and tumor regression were found between the two groups.CONCLUSION: Overlapping-spot PDT under appropriate treatment parameters and strategies is as effective and safe as single-spot PDT for treating symptomatic circumscribed choroidal hemangioma. Improved or stabilized visual acuity was achieved as a result of tumor regression.

  8. Spots educativos : un modelo de evaluación creativa

    Directory of Open Access Journals (Sweden)

    Jorge Montalvo-Castro

    2010-03-01

    Full Text Available En esta investigación se precisan las semejanzas y diferencias entre los spots comerciales, sociales y educativos. Se analizan el problema de la eficacia de los spots y el papel de la creatividad. Además, se plantea la necesidad de contar con un modelo apropiado de evaluación de spots educativos que tome en cuenta ciertos principios de la teoría del aprendizaje significativo de David Ausubel. Finalmente, se diseña y propone un modelo de evaluación creativa —tipo lista de cotejo— que es sometido a una prueba experimental y cuyos resultados apoyan el planteamiento.

  9. Weld Spot Detection by Color Segmentation and Template Convolution

    Science.gov (United States)

    Cambrini, Luigi; Biber, Jürgen; Hönigmann, Dieter; Löhndorf, Maike

    2007-12-01

    There is a need of non-destructive evaluation of the quality of steel spot welds. A computer-vision based solution is presented performing the analysis of the weld spot imprints left by the electrode on the protection bands. In this paper we propose two different methods to locate the position of the weld spot imprint as a first step in order to verify the quality of the welding process; both methods consist of two stages: (i) the use of the X channel of the XYZ color space as a proper representation, and (ii) the analysis of this image channel by employing specific algorithms.

  10. Spot: a new Monte Carlo solver for fast alpha particles

    International Nuclear Information System (INIS)

    Schneider, M.; Eriksson, L.G.; Basiuk, V.; Imbeaux, F.

    2004-01-01

    The predictive transport code CRONOS has been augmented by an orbit following Monte Carlo code, SPOT (Simulation of Particle Orbits in a Tokamak). The SPOT code simulates the dynamics of nonthermal particles, and takes into account effects of finite orbit width and collisional transport of fast ions. Recent developments indicate that it might be difficult to avoid, at least transiently, current holes in a reactor. They occur already on existing tokamaks during advanced tokamak scenarios. The SPOT code has been used to study the alpha particle behaviour in the presence of current holes for both JET and ITER relevant parameters. (authors)

  11. Reflections on the reporting of the uranium spot price

    International Nuclear Information System (INIS)

    Novak, E.D.

    1984-01-01

    Reporting of the Spot Uranium Price does not represent the uranium market, but actually represents the extremities of a market. The Spot Prices tend to cause instabilities in the market if relied upon too heavily and an excessive use will actually support a questionable transition from a fuel supply industry to a commodities industry. Utility fuel buyers and uranium sellers must be careful how they use the Spot Price, or they will continue to create an unstable supply/demand relationship. But, since we all rely upon statistics for the illusion of independence, we may get the commodities market, assisted along by the information people, whether we want it or not

  12. Modelling energy spot prices by Lévy semistationary processes

    DEFF Research Database (Denmark)

    Barndorff-Nielsen, Ole; Benth, Fred Espen; Veraart, Almut

    This paper introduces a new modelling framework for energy spot prices based on Lévy semistationary processes. Lévy semistationary processes are special cases of the general class of ambit processes. We provide a detailed analysis of the probabilistic properties of such models and we show how the...... they are able to capture many of the stylised facts observed in energy markets. Furthermore, we derive forward prices based on our spot price model. As it turns out, many of the classical spot models can be embedded into our novel modelling framework....

  13. Weld Spot Detection by Color Segmentation and Template Convolution

    International Nuclear Information System (INIS)

    Cambrini, Luigi; Biber, Juergen; Hoenigmann, Dieter; Loehndorf, Maike

    2007-01-01

    There is a need of non-destructive evaluation of the quality of steel spot welds. A computer-vision based solution is presented performing the analysis of the weld spot imprints left by the electrode on the protection bands. In this paper we propose two different methods to locate the position of the weld spot imprint as a first step in order to verify the quality of the welding process; both methods consist of two stages: (i) the use of the X channel of the XYZ color space as a proper representation, and (ii) the analysis of this image channel by employing specific algorithms

  14. Spot Welding of 6061 Aluminum Alloy by Friction Stir Spot Welding Process

    Directory of Open Access Journals (Sweden)

    M. A. Tashkandi

    2017-06-01

    Full Text Available This study was focused on the effect of welding parameters on the lap-shear fracture load of the welded joints prepared by friction stir spot welding. Four different weld parameters were analyzed: rotational speed, dwell time, pin length and shoulder size of the welding tool. It was found that the lap-shear fracture load increases with an increase of the welding parameters to a limited value and decreases with further increase. The strong welded joints failed under nugget-pull out fracture.

  15. Simultaneous determination of 3-hydroxypropionic acid, methylmalonic acid and methylcitric acid in dried blood spots: Second-tier LC-MS/MS assay for newborn screening of propionic acidemia, methylmalonic acidemias and combined remethylation disorders.

    Directory of Open Access Journals (Sweden)

    Péter Monostori

    Full Text Available Increased propionylcarnitine levels in newborn screening are indicative for a group of potentially severe disorders including propionic acidemia (PA, methylmalonic acidemias and combined remethylation disorders (MMACBL. This alteration is relatively non-specific, resulting in the necessity of confirmation and differential diagnosis in subsequent tests. Thus, we aimed to develop a multiplex approach for concurrent determination of 3-hydroxypropionic acid, methylmalonic acid and methylcitric acid from the same dried blood spot (DBS as in primary screening (second-tier test. We also set out to validate the method using newborn and follow-up samples of patients with confirmed PA or MMACBL.The assay was developed using liquid chromatography-tandem mass spectrometry and clinically validated with retrospective analysis of DBS samples from PA or MMACBL patients.Reliable determination of all three analytes in DBSs was achieved following simple and fast (<20 min sample preparation without laborious derivatization or any additional pipetting steps. The method clearly distinguished the pathological and normal samples and differentiated between PA and MMACBL in all stored newborn specimens. Methylcitric acid was elevated in all PA samples; 3-hydroxypropionic acid was also high in most cases. Methylmalonic acid was increased in all MMACBL specimens; mostly together with methylcitric acid.A liquid chromatography-tandem mass spectrometry assay allowing simultaneous determination of the biomarkers 3-hydroxypropionic acid, methylmalonic acid and methylcitric acid in DBSs has been developed. The assay can use the same specimen as in primary screening (second-tier test which may reduce the need for repeated blood sampling. The presented preliminary findings suggest that this method can reliably differentiate patients with PA and MMACBL in newborn screening. The validated assay is being evaluated prospectively in a pilot project for extension of the German newborn

  16. Simultaneous determination of 3-hydroxypropionic acid, methylmalonic acid and methylcitric acid in dried blood spots: Second-tier LC-MS/MS assay for newborn screening of propionic acidemia, methylmalonic acidemias and combined remethylation disorders.

    Science.gov (United States)

    Monostori, Péter; Klinke, Glynis; Richter, Sylvia; Baráth, Ákos; Fingerhut, Ralph; Baumgartner, Matthias R; Kölker, Stefan; Hoffmann, Georg F; Gramer, Gwendolyn; Okun, Jürgen G

    2017-01-01

    Increased propionylcarnitine levels in newborn screening are indicative for a group of potentially severe disorders including propionic acidemia (PA), methylmalonic acidemias and combined remethylation disorders (MMACBL). This alteration is relatively non-specific, resulting in the necessity of confirmation and differential diagnosis in subsequent tests. Thus, we aimed to develop a multiplex approach for concurrent determination of 3-hydroxypropionic acid, methylmalonic acid and methylcitric acid from the same dried blood spot (DBS) as in primary screening (second-tier test). We also set out to validate the method using newborn and follow-up samples of patients with confirmed PA or MMACBL. The assay was developed using liquid chromatography-tandem mass spectrometry and clinically validated with retrospective analysis of DBS samples from PA or MMACBL patients. Reliable determination of all three analytes in DBSs was achieved following simple and fast (<20 min) sample preparation without laborious derivatization or any additional pipetting steps. The method clearly distinguished the pathological and normal samples and differentiated between PA and MMACBL in all stored newborn specimens. Methylcitric acid was elevated in all PA samples; 3-hydroxypropionic acid was also high in most cases. Methylmalonic acid was increased in all MMACBL specimens; mostly together with methylcitric acid. A liquid chromatography-tandem mass spectrometry assay allowing simultaneous determination of the biomarkers 3-hydroxypropionic acid, methylmalonic acid and methylcitric acid in DBSs has been developed. The assay can use the same specimen as in primary screening (second-tier test) which may reduce the need for repeated blood sampling. The presented preliminary findings suggest that this method can reliably differentiate patients with PA and MMACBL in newborn screening. The validated assay is being evaluated prospectively in a pilot project for extension of the German newborn screening

  17. [Study on Hexagonal Super-Lattice Pattern with Light Spot and Dim Spot in Dielectric Barrier Discharge by Optical Emission Spectra].

    Science.gov (United States)

    Liu, Ying; Dong, Li-fang; Niu, Xue-jiao; Zhang, Chao

    2016-02-01

    The hexagonal super-lattice pattern composed of the light spot and the dim spot is firstly observed and investigated in the discharge of gas mixture of air and argon by using the dielectric barrier discharge device with double water electrodes. It is found that the dim spot is located at the center of its surrounding three light spots by observing the discharge image. Obviously, the brightness of the light spot and the dim spot are different, which indicates that the plasma states of the light spot and the dim spot may be different. The optical emission spectrum method is used to further study the several plasma parameters of the light spot and the dim spot in different argon content. The emission spectra of the N₂ second positive band (C³IIu --> B³IIg) are measured, from which the molecule vibration temperatures of the light spot and the dim spot are calculated. Based on the relative intensity ratio of the line at 391.4 nm and the N₂ line at 394.1 nm, the average electron energies of the light spot and the dim spot are investigated. The broadening of spectral line 696.57 nm (2P₂-1S₅) is used to study the electron densities of the light spot and the dim spot. The experiment shows that the molecule vibration temperature, average electron energy and the electron density of the dim spot are higher than those of the light spot in the same argon content. The molecule vibration temperature and electron density of the light spot and dim spot increase with the argon content increasing from 70% to 95%, while average electron energies of the light spot and dim spot decrease gradually. The short-exposure image recorded by a high speed video camera shows that the dim spot results from the surface discharges (SDs). The surface discharge induced by the volume discharge (VD) has the decisive effect on the formation of the dim spot. The experiment above plays an important role in studying the formation mechanism of the hexagonal super-lattice pattern with light spot and

  18. Metallography of Battery Resistance Spot Welds

    Science.gov (United States)

    Martinez, J. E.; Johannes, L. B.; Gonzalez, D.; Yayathi, S.; Figuered, J. M.; Darcy, E. C.; Bilc, Z. M.

    2015-01-01

    Li-ion cells provide an energy dense solution for systems that require rechargeable electrical power. However, these cells can undergo thermal runaway, the point at which the cell becomes thermally unstable and results in hot gas, flame, electrolyte leakage, and in some cases explosion. The heat and fire associated with this type of event is generally violent and can subsequently cause damage to the surrounding system or present a dangerous risk to the personnel nearby. The space flight environment is especially sensitive to risks particularly when it involves potential for fire within the habitable volume of the International Space Station (ISS). In larger battery packs such as Robonaut 2 (R2), numerous Li-ion cells are placed in parallel-series configurations to obtain the required stack voltage and desired run-time or to meet specific power requirements. This raises a second and less obvious concern for batteries that undergo certification for space flight use: the joining quality at the resistance spot weld of battery cells to component wires/leads and battery tabs, bus bars or other electronic components and assemblies. Resistance spot welds undergo materials evaluation, visual inspection, conductivity (resistivity) testing, destructive peel testing, and metallurgical examination in accordance with applicable NASA Process Specifications. Welded components are cross-sectioned to ensure they are free of cracks or voids open to any exterior surface. Pore and voids contained within the weld zone but not open to an exterior surface, and are not determined to have sharp notch like characteristics, shall be acceptable. Depending on requirements, some battery cells are constructed of aluminum canisters while others are constructed of steel. Process specific weld schedules must be developed and certified for each possible joining combination. The aluminum canisters' positive terminals were particularly difficult to weld due to a bi-metal strip that comes ultrasonically

  19. Effect of tool rotational speed and penetration depth on dissimilar aluminum alloys friction stir spot welds

    Directory of Open Access Journals (Sweden)

    Joaquín M. Piccini

    2017-03-01

    Full Text Available In the last years, the automotive industry is looking for the use of aluminum parts in replace of steel parts in order to reduce the vehicles weight. These parts have to be joined, for instance, by welding processes. The more common welding process in the automotive industry is the Resistance Spot Welding (RSW technique. However, RSW of aluminum alloys has many disadvantages. Regarding this situation, a variant of the Friction Stir Welding process called Friction Stir Spot Welding (FSSW has been developed, showing a strong impact in welding of aluminum alloys and dissimilar materials in thin sheets. Process parameters affect the characteristics of the welded joints. However, the information available on this topic is scarce, particularly for dissimilar joints and thin sheets. The aim of this work was to study the effect of the rotational speed and the tool penetration depth on the characteristics of dissimilar FSS welded joints. Defects free joints have been achieved with higher mechanical properties than the ones reported. The maximum fracture load was 5800 N. It was observed that the effective joint length of the welded spots increased with the tool penetration depth, meanwhile the fracture load increased and then decreased. Finally, welding at 1200 RPM produced welded joints with lower mechanical properties than the ones achieved at 680 and 903 RPM.

  20. 8-spot smFRET analysis using two 8-pixel SPAD arrays.

    Science.gov (United States)

    Ingargiola, Antonino; Panzeri, Francesco; Sarkosh, Niusha; Gulinatti, Angelo; Rech, Ivan; Ghioni, Massimo; Weiss, Shimon; Michalet, Xavier

    2013-02-22

    Single-molecule Förster resonance energy transfer (smFRET) techniques are now widely used to address outstanding problems in biology and biophysics. In order to study freely diffusing molecules, current approaches consist in exciting a low concentration (pixel Single-Photon Avalanche Diodes (SPADs). A large enough number of single-molecule bursts must be accumulated in order to compute FRET efficiencies with sufficient statistics. As a result, the minimum timescale of observable phenomena is set by the minimum acquisition time needed for accurate measurements, typically a few minutes or more, limiting this approach mostly to equilibrium studies. Increasing smFRET analysis throughput would allow studying dynamics with shorter timescales. We recently demonstrated a new multi-spot excitation approach, employing a novel multi-pixel SPAD array, using a simplified dual-view setup in which a single 8-pixel SPAD array was used to collect FRET data from 4 independent spots. In this work we extend our results to 8 spots and use two 8-SPAD arrays to collect donor and acceptor photons and demonstrate the capabilities of this system by studying a series of doubly labeled dsDNA samples with different donor-acceptor distances ranging from low to high FRET efficiencies. Our results show that it is possible to enhance the throughput of smFRET measurements in solution by almost one order of magnitude, opening the way for studies of single-molecule dynamics with fast timescale once larger SPAD arrays become available.

  1. An improved microculture-hemolytic spot assay for the study of carrier-specific antibody responses.

    Science.gov (United States)

    Kotkes, P; Weisman, Z; Mozes, E; Bentwich, Z

    1984-11-30

    A microculture system based on limiting dilution and a hemolytic spot assay was adapted for study of the carrier-specific anti-hapten response in vitro. Spleen or lymph node cells from normal mice or mice immunized with NIP-ovalbumin (NIP-OVA) or NIP-human thyroglobulin (NIP-Tg) were cultured for 5 days by the microculture technique. The anti-hapten (anti-NIP) response was measured by assaying the supernatants of the microcultures in a hemolytic spot test with NIP coupled to sheep red blood cells. A micro-ELISA reader was adapted to read the degree of lysis in the spot assay which gives an objective quantitation of the degree of lysis and thus reduces the number of culture replicates. In vivo induced specific helper cells in mice immunized with the carrier protein, human thyroglobulin, as well as carrier-specific T cell factors, gave rise to carrier-specific anti-NIP responses. The microculture system may enhance the expression of T-cell helper function when suppressor cells or their precursors are present in the initial cell preparation.

  2. More than 10 years experience of beam monitoring with the Gantry 1 spot scanning proton therapy facility at PSI

    International Nuclear Information System (INIS)

    Lin Shixiong; Boehringer, Terence; Coray, Adolf; Grossmann, Martin; Pedroni, Eros

    2009-01-01

    Purpose: The beam monitoring equipments developed for the first PSI spot scanning proton therapy facility, Gantry 1, have been successfully used for more than 10 years. The purpose of this article is to summarize the author's experience in the beam monitoring technique for dynamic proton scanning. Methods: The spot dose delivery and verification use two independent beam monitoring and computer systems. In this article, the detector construction, electronic system, dosimetry, and quality assurance results are described in detail. The beam flux monitor is calibrated with a Faraday cup. The beam position monitoring is realized by measuring the magnetic fields of deflection magnets with Hall probes before applying the spot and by checking the beam position and width with an ionization strip chamber after the spot delivery. Results: The results of thimble ionization chamber dosimetry measurements are reproducible (with a mean deviation of less than 1% and a standard deviation of 1%). The resolution in the beam position measurement is of the order of a tenth of a millimeter. The tolerance of the beam position delivery and monitoring during scanning is less than 1.5 mm. Conclusions: The experiences gained with the successful operation of Gantry 1 represent a unique and solid background for the development of a new system, Gantry 2, in order to perform new advanced scanning techniques.

  3. More than 10 years experience of beam monitoring with the Gantry 1 spot scanning proton therapy facility at PSI

    Energy Technology Data Exchange (ETDEWEB)

    Lin Shixiong; Boehringer, Terence; Coray, Adolf; Grossmann, Martin; Pedroni, Eros [Center for Proton Therapy, Paul Scherrer Institute, CH-5232 Villigen PSI (Switzerland)

    2009-11-15

    Purpose: The beam monitoring equipments developed for the first PSI spot scanning proton therapy facility, Gantry 1, have been successfully used for more than 10 years. The purpose of this article is to summarize the author's experience in the beam monitoring technique for dynamic proton scanning. Methods: The spot dose delivery and verification use two independent beam monitoring and computer systems. In this article, the detector construction, electronic system, dosimetry, and quality assurance results are described in detail. The beam flux monitor is calibrated with a Faraday cup. The beam position monitoring is realized by measuring the magnetic fields of deflection magnets with Hall probes before applying the spot and by checking the beam position and width with an ionization strip chamber after the spot delivery. Results: The results of thimble ionization chamber dosimetry measurements are reproducible (with a mean deviation of less than 1% and a standard deviation of 1%). The resolution in the beam position measurement is of the order of a tenth of a millimeter. The tolerance of the beam position delivery and monitoring during scanning is less than 1.5 mm. Conclusions: The experiences gained with the successful operation of Gantry 1 represent a unique and solid background for the development of a new system, Gantry 2, in order to perform new advanced scanning techniques.

  4. Blind spot monitoring in light vehicles -- system performance.

    Science.gov (United States)

    2014-07-01

    This report summarizes findings of a small population study of blind spot monitoring systems (BSM) installed by : original vehicle manufacturers on standard production vehicles. The primary goals of these tests were to simulate real-world driving sce...

  5. Analysis and validation of laser spot weld-induced distortion

    Energy Technology Data Exchange (ETDEWEB)

    Knorovsky, G.A.; Kanouff, M.P.; Maccallum, D.O.; Fuerschbach, P.W.

    1999-12-09

    Laser spot welding is an ideal process for joining small parts with tight tolerances on weld size, location, and distortion, particularly those with near-by heat sensitive features. It is also key to understanding the overlapping laser spot seam welding process. Rather than attempting to simulate the laser beam-to-part coupling (particularly if a keyhole occurs), it was measured by calorimetry. This data was then used to calculate the thermal and structural response of a laser spot welded SS304 disk using the finite element method. Five combinations of process parameter values were studied. Calculations were compared to experimental data for temperature and distortion profiles measured by thermocouples and surface profiling. Results are discussed in terms of experimental and modeling factors. The authors then suggest appropriate parameters for laser spot welding.

  6. Spot-Welding Gun With Adjustable Pneumatic Spring

    Science.gov (United States)

    Burley, Richard K.

    1990-01-01

    Proposed spot-welding gun equipped with pneumatic spring, which could be bellows or piston and cylinder, exerts force independent of position along stroke. Applies accurate controlled force to joint welded, without precise positioning at critical position within stroke.

  7. NNDSS - Table II. Spotted Fever Rickettsiosis to Syphilis

    Data.gov (United States)

    U.S. Department of Health & Human Services — NNDSS - Table II. Spotted Fever Rickettsiosis to Syphilis - 2017. In this Table, provisional cases of selected notifiable diseases (≥1,000 cases reported during the...

  8. NNDSS - Table II. Spotted Fever Rickettsiosis to Syphilis

    Data.gov (United States)

    U.S. Department of Health & Human Services — NNDSS - Table II. Spotted Fever Rickettsiosis to Syphilis - 2014.In this Table, all conditions with a 5-year average annual national total of more than or equals...

  9. Characterization of a tailless white spot syndrome virus from ...

    African Journals Online (AJOL)

    WSSV) but without tail-like extension was identified and characterized from diseased Penaeus vannamei and moribund Procambarus clarkia. Contrary to previous reports, white spots were not observed on the carapace of the diseased P.

  10. Gnomonia canker, shoot blight, and leaf spot of yellow birch.

    Science.gov (United States)

    Kenneth J. Jr. Kessler

    1978-01-01

    Describes a canker, shoot blight, and leaf spot disease of yellow birch seedlings in the northern Great Lakes region and tells how and when trees become infected by the fungal causal agent, Gnomonia setacea.

  11. Performance evaluation of spot detection algorithms in fluorescence microscopy images

    CSIR Research Space (South Africa)

    Mabaso, M

    2012-10-01

    Full Text Available Detection of messenger Ribonucleic Acid (mRNA) spots in fluorescence microscopy images is of great importance for biologists seeking better understanding of cell functionality. Fluorescence microscopy and specific staining methods make biological...

  12. Pregnancy Complications: Bleeding and Spotting from the Vagina

    Science.gov (United States)

    ... miscarry have bleeding or spotting before the miscarriage. Ectopic pregnancy. This is when a fertilized egg implants itself ... of the uterus and begins to grow. An ectopic pregnancy cannot result in the birth of a baby. ...

  13. Transportation conformity particulate matter hot-spot air quality modeling.

    Science.gov (United States)

    2013-07-01

    In light of the new development in particulate matter (PM) hot-spot regulations and Illinois Department : of Transportation (IDOT)s National Environmental Policy Act (NEPA) documentation requirements, : this project is intended to (1) perform and ...

  14. NNDSS - Table II. Spotted Fever Rickettsiosis to Syphilis

    Data.gov (United States)

    U.S. Department of Health & Human Services — NNDSS - Table II. Spotted Fever Rickettsiosis to Syphilis - 2017. In this Table, provisional cases of selected notifiable diseases (≥1,000 cases reported during...

  15. NNDSS - Table II. Spotted Fever Rickettsiosis to Syphilis

    Data.gov (United States)

    U.S. Department of Health & Human Services — NNDSS - Table II. Spotted Fever Rickettsiosis to Syphilis - 2015.In this Table, provisional cases of selected notifiable diseases (≥1,000 cases reported during the...

  16. NNDSS - Table II. Spotted Fever Rickettsiosis to Syphilis

    Data.gov (United States)

    U.S. Department of Health & Human Services — NNDSS - Table II. Spotted Fever Rickettsiosis to Syphilis - 2016. In this Table, provisional* cases of selected† notifiable diseases (≥1,000 cases reported during...

  17. Spot table - RPD | LSDB Archive [Life Science Database Archive metadata

    Lifescience Database Archive (English)

    Full Text Available ended gel image of the spot. Mass Spectrometry Accession No. Accession No. of homologous protein by Mascot Analysis. Mass Spectrometr...y Homologous Protein Definition of homologous protein by Mascot Analysis. Mass Spectrometry

  18. Spotting Cheetahs: Identifying Individuals by Their Footprints

    Science.gov (United States)

    Jewell, Zoe C.; Alibhai, Sky K.; Weise, Florian; Munro, Stuart; Van Vuuren, Marlice; Van Vuuren, Rudie

    2016-01-01

    The cheetah (Acinonyx jubatus) is Africa's most endangered large felid and listed as Vulnerable with a declining population trend by the IUCN1. It ranges widely over sub-Saharan Africa and in parts of the Middle East. Cheetah conservationists face two major challenges, conflict with landowners over the killing of domestic livestock, and concern over range contraction. Understanding of the latter remains particularly poor2. Namibia is believed to support the largest number of cheetahs of any range country, around 30%, but estimates range from 2,9053 to 13,5204. The disparity is likely a result of the different techniques used in monitoring. Current techniques, including invasive tagging with VHF or satellite/GPS collars, can be costly and unreliable. The footprint identification technique5 is a new tool accessible to both field scientists and also citizens with smartphones, who could potentially augment data collection. The footprint identification technique analyzes digital images of footprints captured according to a standardized protocol. Images are optimized and measured in data visualization software. Measurements of distances, angles, and areas of the footprint images are analyzed using a robust cross-validated pairwise discriminant analysis based on a customized model. The final output is in the form of a Ward's cluster dendrogram. A user-friendly graphic user interface (GUI) allows the user immediate access and clear interpretation of classification results. The footprint identification technique algorithms are species specific because each species has a unique anatomy. The technique runs in a data visualization software, using its own scripting language (jsl) that can be customized for the footprint anatomy of any species. An initial classification algorithm is built from a training database of footprints from that species, collected from individuals of known identity. An algorithm derived from a cheetah of known identity is then able to classify free

  19. Fungicide efficacy in peach rusty spot control in Serbia

    OpenAIRE

    Dolovac Nenad; Miletić Novica; Aleksić Goran; Savić Dušan; Živković Svetlana; Trkulja Nenad; Bulajić Aleksandra

    2010-01-01

    Rusty Spot has long been known as a harmful peach disease in many parts of the world. During the past several years, rusty spot infection of the late-maturing peach cultivars (Summerset, Suncrest, Fayette and O’Henry) caused significant yield losses in Serbia. Although the etiology of the disease is still unknown, there are numerous studies attempting to set a strategy for its control and recommend appropriate chemical and other peach protection methods. Ho...

  20. FOTS: Fast Oriented Text Spotting with a Unified Network

    OpenAIRE

    Liu, Xuebo; Liang, Ding; Yan, Shi; Chen, Dagui; Qiao, Yu; Yan, Junjie

    2018-01-01

    Incidental scene text spotting is considered one of the most difficult and valuable challenges in the document analysis community. Most existing methods treat text detection and recognition as separate tasks. In this work, we propose a unified end-to-end trainable Fast Oriented Text Spotting (FOTS) network for simultaneous detection and recognition, sharing computation and visual information among the two complementary tasks. Specially, RoIRotate is introduced to share convolutional features ...

  1. Resistance Spot Welding with Middelfrequency-Inverter Weling Gun

    DEFF Research Database (Denmark)

    Rasmussen, Mogens H.

    The paper presents the results of investigations concerning the process stability and weldability lobes for uncoated sheets of 1.0 mm thickness when performing resistance spot welding with a middlefrequency-inverter welding gun......The paper presents the results of investigations concerning the process stability and weldability lobes for uncoated sheets of 1.0 mm thickness when performing resistance spot welding with a middlefrequency-inverter welding gun...

  2. Complete mitochondrial DNA sequence of the Qianshao spotted pig.

    Science.gov (United States)

    Xu, Dong; Chai, Yu-Lan; Jiang, Juan; He, Chang-Qing; Ma, Hai-Ming

    2015-01-01

    The complete mitochondrial genome sequence of Qianshao spotted pig was first determined in this study. The mitogenome (16,700 bp) consists of 22 tRNA genes, 2 ribosomal RNA genes, 13 protein-coding genes and 1 control region (D-loop region). The complete mitochondrial genome sequence of the Qianshao spotted pig enriches data resource for further study in genetic mechanism.

  3. Onset of breakdown and formation of cathode spots

    International Nuclear Information System (INIS)

    Schwirzke, F.; Hallal, M.P. Jr.; Maruyama, X.K.

    1992-01-01

    The initial phase of onset of electrical breakdown in a vacuum discharge is characterized by very rapid ionization of surface material which leads to a kind of ''explosive'' plasma formation on electrodes. As an increasing electric field is applied between the two electrodes of vacuum diode the ionization process is initiated by field emission of electrons from highly localized spots on the cathode surface. Despite the fundamental importance of cathode spots for the breakdown process, the structure of cathode spots and the fast ionization rates of surface layers were riot fully understood. Besides joule heating of the field emitting spot, the electrons also desorb contaminants and ionize some of the released neutrals. Ions produced a short distance (∼ 1μm) from the spot are accelerated back towards the cathode. This ion bombardment leads to surface heating of the spot. Calculations of the power deposition show that ion surface heating is initially orders of magnitude larger than joule heating. Ion bombardment is especially important at low initial current densities since it leads efficiently to further desorption arid sputtering of neutrals from the surface and hence increases the neutral density which in turn increases the ionization rate. As more ions are produced, a positive space charge layer forms which enhances the electric field and thus strongly enhances the field emitted electron current. Surface heating and the build-up of positive space charge rapidly lead to further enhanced field emission and finally thermionic electron emission. The localized build-up plasma above the electron emitting spot naturally leads to pressure and electric field distributions which ignite unipolar arcs. The large electron current of the unipolar arc and large ion sputtering rates cause the ''explosion'' of surface material into the dense plasma of a cathode spot

  4. On the burn topology of hot-spot-initiated reactions

    Energy Technology Data Exchange (ETDEWEB)

    Hill, Larry G [Los Alamos National Laboratory; Zimmermann, Bjorn [WOLFRAM RESEARCH INC.; Nichols, Albert L [LLNL

    2009-01-01

    We determine the reaction progress function for an ideal hot spot model problem. The considered problem has an exact analytic solution that can derived from a reduction of Nichols statistical hot spot model. We perform numerical calculations to verify the analytic solution and to illustrate the error realized in real, finite systems. We show how the baseline problem, which does not distinguish between the reactant and product densities, can be scaled to handle general cases for which the two densities differ.

  5. Damage tolerance reliability analysis of automotive spot-welded joints

    International Nuclear Information System (INIS)

    Mahadevan, Sankaran; Ni Kan

    2003-01-01

    This paper develops a damage tolerance reliability analysis methodology for automotive spot-welded joints under multi-axial and variable amplitude loading history. The total fatigue life of a spot weld is divided into two parts, crack initiation and crack propagation. The multi-axial loading history is obtained from transient response finite element analysis of a vehicle model. A three-dimensional finite element model of a simplified joint with four spot welds is developed for static stress/strain analysis. A probabilistic Miner's rule is combined with a randomized strain-life curve family and the stress/strain analysis result to develop a strain-based probabilistic fatigue crack initiation life prediction for spot welds. Afterwards, the fatigue crack inside the base material sheet is modeled as a surface crack. Then a probabilistic crack growth model is combined with the stress analysis result to develop a probabilistic fatigue crack growth life prediction for spot welds. Both methods are implemented with MSC/NASTRAN and MSC/FATIGUE software, and are useful for reliability assessment of automotive spot-welded joints against fatigue and fracture

  6. Spot market activity remains weak as prices continue to fall

    International Nuclear Information System (INIS)

    Anon.

    1996-01-01

    A summary of financial data for the uranium spot market in November 1996 is provided. Price ranges for the restricted and unrestricted markets, conversion, and separative work are listed, and total market volume and new contracts are noted. Transactions made are briefly described. Deals made and pending in the spot concentrates, medium and long-term, conversion, and markets are listed for U.S. and non-U.S. buyers. Spot market activity increased in November with just over 1.0 million lbs of U3O8 equivalent being transacted compared to October's total of 530,000 lbs of U3O8 equivalent. The restricted uranium spot market price range slipped from $15.50-$15.70/lb U3O8 last month to $14.85/lb - $15.25/lb U3O8 this month. The unrestricted uranium spot market price range also slipped to $14.85/lb - $15.00/lb this month from $15.00/lb - $15.45/lb in October. Spot prices for conversion and separative work units remained at their October levels

  7. Cognitive sophistication does not attenuate the bias blind spot.

    Science.gov (United States)

    West, Richard F; Meserve, Russell J; Stanovich, Keith E

    2012-09-01

    The so-called bias blind spot arises when people report that thinking biases are more prevalent in others than in themselves. Bias turns out to be relatively easy to recognize in the behaviors of others, but often difficult to detect in one's own judgments. Most previous research on the bias blind spot has focused on bias in the social domain. In 2 studies, we found replicable bias blind spots with respect to many of the classic cognitive biases studied in the heuristics and biases literature (e.g., Tversky & Kahneman, 1974). Further, we found that none of these bias blind spots were attenuated by measures of cognitive sophistication such as cognitive ability or thinking dispositions related to bias. If anything, a larger bias blind spot was associated with higher cognitive ability. Additional analyses indicated that being free of the bias blind spot does not help a person avoid the actual classic cognitive biases. We discuss these findings in terms of a generic dual-process theory of cognition.

  8. Duodenal White Spots Mimicking Intestinal Candidiasis: Report of Case

    Directory of Open Access Journals (Sweden)

    Ozgur Turk

    2015-12-01

    Full Text Available Duodenal white spots are mentioned in these nonspecific lesions until recently. Although there is not enough studies about duedonal white spots yet; these lesions described in a separate syndrome. Here now we reported a case that we diagnosed multiple Duodenal white spots mimicking intestinal candidiasis. Clinical manifestation and endoscopic appearance of lesions gave rise to thought intestinal candidiasis histopathological examination revealed us several duodenitis. There was no evidence of fungal infection in PAS staining. Early after endoscopy patient took treatment of Lansoprozole at the 30 mg dose and bismuth salicylate. Patients compliant declined and control endoscopy exposed white duodenal spots cleared away three months later. Duodenal white spots are becoming to be designated as a separate disease even a syndrome. Etiology of duodenal white spots must be determined carefully during endoscopy. Sometimes it is difficult to make the correct diagnosis by appearance of lesion; in such cases histopathological examination can be useful both differential diagnosis of disease and determination of etiological factor. [J Contemp Med 2015; 5(4.000: 249-252

  9. Joining of Dissimilar alloy Sheets (Al 6063&AISI 304 during Resistance Spot Welding Process: A Feasibility Study for Automotive industry

    Directory of Open Access Journals (Sweden)

    Reddy Sreenivasulu

    2014-12-01

    Full Text Available Present design trends in automotive manufacture have shifted emphasis to alternative lightweight materials in order to achieve higher fuel efficiency and to bring down vehicle emission. Although some other joining techniques are more and more being used, spot welding still remains the primary joining method in automobile manufacturing so far. Spot welds for automotive applications should have a sufficiently large diameter, so that nugget pullout mode is the dominant failure mode. Interfacial mode is unacceptable due to its low load carrying and energy absorption capability. Strength tests with different static loading were performed in, to reveal the failure mechanisms for the lap-shear geometry and the cross-tension geometry. Based on the literature survey performed, venture into this work was amply motivated by the fact that a little research work has been conducted to joining of dissimilar materials like non ferrous to ferrous. Most of the research works concentrated on joining of different materials like steel to steel or aluminium alloy to aluminium alloy by resistance spot welding. In this work, an experimental study on the resistance spot weldability of aluminium alloy (Al 6063 and austenitic stainless steel (AISI304 sheets, which are lap joined by using a pedestal type resistance spot welding machine. Welding was conducted using a 45-deg truncated cone copper electrode with 10-mm face diameter. The weld nugget diameter, force estimation under lap shear test and T – peel test were investigated using digital type tensometer attached with capacitive displacement transducer (Mikrotech, Bangalore, Model: METM2000ER1. The results shows that joining of Al 6063 and AISI 304 thin sheets by RSW method are feasible for automotive structural joints where the loads are below 1000N act on them, it is observed that by increasing the spots per unit length, then the joint with standing strength to oppose failure is also increased linearly incase of

  10. Analysis of Using Acoustic Microscopy to Evaluate Defects in Spot Welding Joints

    Directory of Open Access Journals (Sweden)

    Korzeniowski M.

    2016-06-01

    Full Text Available The article presents the possibilities of using acoustic microscopy to evaluate defects in resistance spot welding joints. For this purpose, the welded joints were made from two grades of aluminium plates EN AW5754 H24 and EN AW6005 T606, which were then subjected to non-destructive testing using acoustic microscopy and conventional destructive testing using traditional light microscopy techniques. Additionally, the study examined the influence of the typical contaminants found in industrial conditions on the quality of the joint.

  11. Comparison of Metallurgical and Ultrasonic Inspections of Galvanized Steel Resistance Spot Welds

    International Nuclear Information System (INIS)

    Potter, Timothy J.; Ghaffari, Bita; Mozurkewich, George; Reverdy, Frederic; Hopkins, Deborah

    2006-01-01

    Metallurgical examination of galvanized steel resistance spot welds was used to gauge the capabilities of two ultrasonic, non-destructive, scanning techniques. One method utilized the amplitude of the echo from the weld faying surface, while the other used the spectral content of the echo train to map the fused area. The specimens were subsequently sectioned and etched, to distinguish the fused, zinc-brazed, and non-fused areas. The spectral maps better matched the metallurgical maps, while the interface-amplitude method consistently overestimated the weld size

  12. Spot14/Spot14R expression may be involved in MSC adipogenic differentiation in patients with adolescent idiopathic scoliosis

    Science.gov (United States)

    WANG, QIFEI; YANG, JUNLIN; LIN, XIANG; HUANG, ZIFANG; XIE, CHAOFAN; FAN, HENGWEI

    2016-01-01

    The aim of the present study was to evaluate the different expression levels of thyroid hormone responsive (THRSP; Spot14)/S14 related, Mig12 (S14R) during bone marrow mesenchymal stem cell (BM-MSC) adipogenesis in adolescent idiopathic scoliosis (AIS) patients. MSCs were retrospectively isolated from AIS patients and controls, and adipogenic differentiation was induced. Total RNA was extracted for Affymetrix 3′-IVT expression profiling microarrays and compared with the results from healthy controls. The results were confirmed by semiquantitative reverse transcription-polymerase chain reaction (RT-PCR) validation and the protein expression levels of Spot14 and its paralogous gene S14R by western blotting and immunohistochemistry. A total of 300 significantly altered mRNAs were detected (111 upregulated and 189 downregulated) and confirmed by RT-qPCR. The mRNA expression levels of seven genes, including Spot14, were altered by >2-fold in AIS patients. Spot14/S14R was selected for further investigation. The results of the western blotting demonstrated that mRNA and protein expression levels of Spot14/S14R were significantly higher in AIS patients than the controls (P<0.05). Immunohistochemistry demonstrated Spot14 was expressed in 85% (17/20 cases) in adipose tissue samples from AIS patients and 23.1% (3/13 cases) of adipose tissue samples from controls. The positive ratio of Spot14 in adipose tissue samples from AIS was significantly higher than the controls (P<0.001). The results of the present study indicated that Spot14/S14R were differently expressed in MSC adipogenesis in AIS patients, and they may be important in the abnormal adipogenic differentiation in AIS. PMID:27082501

  13. Spot-scanning beam delivery with laterally- and longitudinally-mixed spot size pencil beams in heavy ion radiotherapy

    Science.gov (United States)

    Yan, Yuan-Lin; Liu, Xin-Guo; Dai, Zhong-Ying; Ma, Yuan-Yuan; He, Peng-Bo; Shen, Guo-Sheng; Ji, Teng-Fei; Zhang, Hui; Li, Qiang

    2017-09-01

    The three-dimensional (3D) spot-scanning method is one of the most commonly used irradiation methods in charged particle beam radiotherapy. Generally, spot-scanning beam delivery utilizes the same size pencil beam to irradiate the tumor targets. Here we propose a spot-scanning beam delivery method with laterally- and longitudinally-mixed size pencil beams for heavy ion radiotherapy. This uses pencil beams with a bigger spot size in the lateral direction and wider mini spread-out Bragg peak (mini-SOBP) to irradiate the inner part of a target volume, and pencil beams with a smaller spot size in the lateral direction and narrower mini-SOBP to irradiate the peripheral part of the target volume. Instead of being controlled by the accelerator, the lateral size of the pencil beam was adjusted by inserting Ta scatterers in the beam delivery line. The longitudinal size of the pencil beam (i.e. the width of the mini-SOBP) was adjusted by tilting mini ridge filters along the beam direction. The new spot-scanning beam delivery using carbon ions was investigated theoretically and compared with traditional spot-scanning beam delivery. Our results show that the new spot-scanning beam delivery has smaller lateral penumbra, steeper distal dose fall-off and the dose homogeneity (1-standard deviation/mean) in the target volume is better than 95%. Supported by Key Project of National Natural Science Foundation of China (U1232207), National Key Technology Support Program of the Ministry of Science and Technology of China (2015BAI01B11), National Key Research and Development Program of the Ministry of Science and Technology of China (2016YFC0904602) and National Natural Science Foundation of China (11075191, 11205217, 11475231, 11505249)

  14. Dried blood spots, valid screening for viral hepatitis and human immunodeficiency virus in real-life

    DEFF Research Database (Denmark)

    Mössner, Belinda K; Staugaard, Benjamin; Jensen, Janne

    2016-01-01

    to a combined nucleic acid test (NAT) for HBV DNA, HCV RNA and HIV RNA. RESULTS: Samples from 404 subjects were screened (85 CHB, 116 CHC, 114 HIV and 99 blood donors). DBS had a sensitivity of > 96% and a specificity of > 98% for the detection of all three infections. NAT testing did not improve sensitivity...

  15. A comparative historical and demographic study of the neuromodulation management techniques of deep brain stimulation for dystonia and cochlear implantation for sensorineural deafness in children.

    Science.gov (United States)

    Hudson, V E; Elniel, A; Ughratdar, I; Zebian, B; Selway, R; Lin, J P

    2017-01-01

    Cochlear implants for sensorineural deafness in children is one of the most successful neuromodulation techniques known to relieve early chronic neurodisability, improving activity and participation. In 2012 there were 324,000 recipients of cochlear implants globally. To compare cochlear implant (CI) neuromodulation with deep brain stimulation (DBS) for dystonia in childhood and explore relations between age and duration of symptoms at implantation and outcome. Comparison of published annual UK CI figures for 1985-2009 with a retrospective cohort of the first 9 years of DBS for dystonia in children at a single-site Functional Neurosurgery unit from 2006 to 14. From 2006 to 14, DBS neuromodulation of childhood dystonia increased by a factor of 3.8 to a total of 126 cases over the first 9 years, similar to the growth in cochlear implants which increased by a factor of 4.1 over a similar period in the 1980s rising to 527 children in 2009. The CI saw a dramatic shift in practice from implantation at >5 years of age at the start of the programme towards earlier implantation by the mid-1990s. Best language results were seen for implantation 4 years, hence implantation children could benefit from cochlear neuromodulation if implanted early. Similar to initial CI use, the majority of children receiving DBS for dystonia in the first 9 years were 5-15 years of age, when the proportion of life lived with dystonia exceeds 90% thus limiting benefits. Early DBS neuromodulation for acquired motor disorders should be explored to maximise the benefits of dystonia reduction in a period of maximal developmental plasticity before the onset of disability. Learning from cochlear implantation, DBS can become an accepted management option in children under the age of 5 years who have a reduced proportion of life lived with dystonia, and not viewed as a last resort reserved for only the most severe cases where benefits may be at their most limited. Copyright © 2016 European Paediatric

  16. Experimental techniques; Techniques experimentales

    Energy Technology Data Exchange (ETDEWEB)

    Roussel-Chomaz, P. [GANIL CNRS/IN2P3, CEA/DSM, 14 - Caen (France)

    2007-07-01

    This lecture presents the experimental techniques, developed in the last 10 or 15 years, in order to perform a new class of experiments with exotic nuclei, where the reactions induced by these nuclei allow to get information on their structure. A brief review of the secondary beams production methods will be given, with some examples of facilities in operation or under project. The important developments performed recently on cryogenic targets will be presented. The different detection systems will be reviewed, both the beam detectors before the targets, and the many kind of detectors necessary to detect all outgoing particles after the reaction: magnetic spectrometer for the heavy fragment, detection systems for the target recoil nucleus, {gamma} detectors. Finally, several typical examples of experiments will be detailed, in order to illustrate the use of each detector either alone, or in coincidence with others. (author)

  17. 7 CFR 27.96 - Quotations in bona fide spot markets.

    Science.gov (United States)

    2010-01-01

    ... determined by the sale of spot cotton in such spot market. Quotations shall be determined and maintained in each designated spot market by the Cotton Division, Agricultural Marketing Service, USDA, as follows... 7 Agriculture 2 2010-01-01 2010-01-01 false Quotations in bona fide spot markets. 27.96 Section 27...

  18. 7 CFR 27.94 - Spot markets for contract settlement purposes.

    Science.gov (United States)

    2010-01-01

    ... CONTAINER REGULATIONS COTTON CLASSIFICATION UNDER COTTON FUTURES LEGISLATION Regulations Spot Markets § 27.94 Spot markets for contract settlement purposes. The following are designated as spot markets for... 7 Agriculture 2 2010-01-01 2010-01-01 false Spot markets for contract settlement purposes. 27.94...

  19. 7 CFR 28.416 - Strict Good Ordinary Light Spotted Color.

    Science.gov (United States)

    2010-01-01

    ... CONTAINER REGULATIONS COTTON CLASSING, TESTING, AND STANDARDS Standards Light Spotted Cotton § 28.416 Strict Good Ordinary Light Spotted Color. Strict Good Ordinary Light Spotted Color is color which in spot or... Cotton Source: 57 FR 34498, Aug. 5, 1992, unless otherwise noted. ...

  20. First Beam Test of Nanometer Spot Size Monitor Using Laser Interferometry

    CERN Document Server

    Walz, D

    2003-01-01

    The nanometer spot size monitor based on the laser interferometry (Laser-Compton Spot Size Monitor) has been tested in FFTB beam line at SLAC. A low emittance beam of 46 GeV electrons, provided by the two-mile linear accelerator, was focused into nanometer spot in the FFTB line, and its transverse dimensions were precisely measured by the spot size monitor.