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Sample records for prospective ecg-gated 256-slice

  1. Dose reduction of up to 89% while maintaining image quality in cardiovascular CT achieved with prospective ECG gating

    NASA Astrophysics Data System (ADS)

    Londt, John H.; Shreter, Uri; Vass, Melissa; Hsieh, Jiang; Ge, Zhanyu; Adda, Olivier; Dowe, David A.; Sabllayrolles, Jean-Louis

    2007-03-01

    We present the results of dose and image quality performance evaluation of a novel, prospective ECG-gated Coronary CT Angiography acquisition mode (SnapShot Pulse, LightSpeed VCT-XT scanner, GE Healthcare, Waukesha, WI), and compare it to conventional retrospective ECG gated helical acquisition in clinical and phantom studies. Image quality phantoms were used to measure noise, slice sensitivity profile, in-plane resolution, low contrast detectability and dose, using the two acquisition modes. Clinical image quality and diagnostic confidence were evaluated in a study of 31 patients scanned with the two acquisition modes. Radiation dose reduction in clinical practice was evaluated by tracking 120 consecutive patients scanned with the prospectively gated scan mode. In the phantom measurements, the prospectively gated mode resulted in equivalent or better image quality measures at dose reductions of up to 89% compared to non-ECG modulated conventional helical scans. In the clinical study, image quality was rated excellent by expert radiologist reviewing the cases, with pathology being identical using the two acquisition modes. The average dose to patients in the clinical practice study was 5.6 mSv, representing 50% reduction compared to a similar patient population scanned with the conventional helical mode.

  2. Achieving consistent image quality with dose optimization in 64-row multidetector computed tomography prospective ECG gated coronary calcium scoring.

    PubMed

    Pan, Zilai; Pang, Lifang; Li, Jianying; Zhang, Huan; Yang, Wenjie; Ding, Bei; Chai, Weimin; Chen, Kemin; Yao, Weiwu

    2011-04-01

    To evaluate the clinical value of a body mass index (BMI) based tube current (mA) selection method for obtaining consistent image quality with dose optimization in MDCT prospective ECG gated coronary calcium scoring. A formula for selecting mA to achieve desired image quality based on patient BMI was established using a control group (A) of 200 MDCT cardiac patients with a standard scan protocol. One hundred patients in Group B were scanned with this BMI-dependent mA for achieving a desired noise level of 18 HU at 2.5 mm slice thickness. The CTDIvol and image noise on the ascending aorta for the two groups were recorded. Two experienced radiologists quantitatively evaluated the image quality using scores of 1-4 with 4 being the highest. The image quality scores had no statistical difference (P = 0.71) at 3.89 ± 0.32, 3.87 ± 0.34, respectively, for groups A and B of similar BMI. The image noise in Group A had linear relationship with BMI. The image noise in Group B using BMI-dependent mA was independent of BMI with average value of 17.9 HU and smaller deviations for the noise values than in Group A (2.0 vs. 2.9 HU). There was a 35% dose reduction with BMI-dependent mA selection method on average with the lowest effective dose being only 0.35 mSv for patient with BMI of 18.3. A quantitative BMI-based mA selection method in MDCT prospective ECG gated coronary calcium scoring has been proposed to obtain a desired and consistent image quality and provide dose optimization across patient population.

  3. Coronary Stent Artifact Reduction with an Edge-Enhancing Reconstruction Kernel – A Prospective Cross-Sectional Study with 256-Slice CT

    PubMed Central

    Tan, Stéphanie; Soulez, Gilles; Diez Martinez, Patricia; Larrivée, Sandra; Stevens, Louis-Mathieu; Goussard, Yves; Mansour, Samer; Chartrand-Lefebvre, Carl

    2016-01-01

    Purpose Metallic artifacts can result in an artificial thickening of the coronary stent wall which can significantly impair computed tomography (CT) imaging in patients with coronary stents. The objective of this study is to assess in vivo visualization of coronary stent wall and lumen with an edge-enhancing CT reconstruction kernel, as compared to a standard kernel. Methods This is a prospective cross-sectional study involving the assessment of 71 coronary stents (24 patients), with blinded observers. After 256-slice CT angiography, image reconstruction was done with medium-smooth and edge-enhancing kernels. Stent wall thickness was measured with both orthogonal and circumference methods, averaging thickness from diameter and circumference measurements, respectively. Image quality was assessed quantitatively using objective parameters (noise, signal to noise (SNR) and contrast to noise (CNR) ratios), as well as visually using a 5-point Likert scale. Results Stent wall thickness was decreased with the edge-enhancing kernel in comparison to the standard kernel, either with the orthogonal (0.97 ± 0.02 versus 1.09 ± 0.03 mm, respectively; p<0.001) or the circumference method (1.13 ± 0.02 versus 1.21 ± 0.02 mm, respectively; p = 0.001). The edge-enhancing kernel generated less overestimation from nominal thickness compared to the standard kernel, both with the orthogonal (0.89 ± 0.19 versus 1.00 ± 0.26 mm, respectively; p<0.001) and the circumference (1.06 ± 0.26 versus 1.13 ± 0.31 mm, respectively; p = 0.005) methods. The edge-enhancing kernel was associated with lower SNR and CNR, as well as higher background noise (all p < 0.001), in comparison to the medium-smooth kernel. Stent visual scores were higher with the edge-enhancing kernel (p<0.001). Conclusion In vivo 256-slice CT assessment of coronary stents shows that the edge-enhancing CT reconstruction kernel generates thinner stent walls, less overestimation from nominal thickness, and better image quality

  4. Qualitative and Quantitative Assessment of Adenosine Triphosphate Stress Whole-Heart Dynamic Myocardial Perfusion Imaging Using 256-Slice Computed Tomography

    PubMed Central

    Kurata, Akira; Kawaguchi, Naoto; Kido, Teruhito; Inoue, Katsuji; Suzuki, Jun; Ogimoto, Akiyoshi; Funada, Jun-ichi; Higaki, Jitsuo; Miyagawa, Masao; Vembar, Mani; Mochizuki, Teruhito

    2013-01-01

    Background The aim of this study was to investigate the correlation of the qualitative transmural extent of hypoperfusion areas (HPA) using stress dynamic whole-heart computed tomography perfusion (CTP) imaging by 256-slice CT with CTP-derived myocardial blood flow (MBF) for the estimation of the severity of coronary artery stenosis. Methods and Results Eleven patients underwent adenosine triphosphate (0.16 mg/kg/min, 5 min) stress dynamic CTP by 256-slice CT (coverage: 8 cm, 0.27 s/rotation), and 9 of the 11 patients underwent coronary angiography (CAG). Stress dynamic CTP (whole–heart datasets over 30 consecutive heart beats in systole without spatial and temporal gaps) was acquired with prospective ECG gating (effective radiation dose: 10.4 mSv). The extent of HPAs was visually graded using a 3-point score (normal, subendocardial, transmural). MBF (ml/100g/min) was measured by deconvolution. Differences in MBF (mean ± standard error) according to HPA and CAG results were evaluated. In 27 regions (3 major coronary territories in 9 patients), 11 coronary stenoses (> 50% reduction in diameter) were observed. In 353 myocardial segments, HPA was significantly related to MBF (P < 0.05; normal 295 ± 94; subendocardial 186 ± 67; and transmural 80 ± 53). Coronary territory analysis revealed a significant relationship between coronary stenosis severity and MBF (P < 0.05; non-significant stenosis [< 50%], 284 ± 97; moderate stenosis [50–70%], 184 ± 74; and severe stenosis [> 70%], 119 ± 69). Conclusion The qualitative transmural extent of HPA using stress whole-heart dynamic CTP imaging by 256-slice CT exhibits a good correlation with quantitative CTP-derived MBF and may aid in assessing the hemodynamic significance of coronary artery disease. PMID:24376774

  5. Comparison of 128-Slice Low-Dose Prospective ECG-Gated CT Scanning and Trans-Thoracic Echocardiography for the Diagnosis of Complex Congenital Heart Disease

    PubMed Central

    Bu, Guilin; Miao, Ying; Bin, Jingwen; Deng, Sheng; Liu, Taowen; Jiang, Hongchun; Chen, Weiping

    2016-01-01

    Objective To compare prospective ECG-gated multi-slice computed tomography (MSCT) and trans-thoracic echocardiography (TTE) in the diagnosis of complex congenital heart disease (CHD). Methods This was a prospective study of consecutive patients with complex CHD (age <7 years) treated at a tertiary hospital between May 2013 and May 2015. All patients were imaged with TTE and prospective ECG-gated 128-slice spiral CT in the week before surgery. Effective radiation dose (ED) was calculated from volume CT dose index (CTDIvol) and dose length product (DLP). Image quality (5-point scale) was assessed independently by two radiologists. Using surgical findings as the reference, the diagnostic capabilities of MSCT and TTE were compared. Results Thirty-five patients (19 males) aged 1.59±1.58 years (range, 3 days to 74 months) were included. CTDIvol, DLP and ED were 0.90±0.24 mGy, 12.9±4.7 mGy∙cm and 0.64±0.21 mSv (range, 0.358–1.196 mSv), respectively. Image quality score was 4.3±0.5, and all images met the diagnostic requirements. The sensitivity, specificity, positive predictive value, and negative predictive value for diagnosing CHD were 97.2%, 99.8%, 99.0%, and 99.5%, respectively, for MSCT, and 90.6%, 99.8%, 99.0%, and 98.4%, respectively, for TTE. MSCT not only had a higher sensitivity than TTE overall (97.2% vs. 90.6%; P<0.05), but was much more sensitive for the diagnosis of extracardiac vascular abnormalities (92.0% vs. 68.0%; P<0.05). Conclusion 128-slice low-dose prospective ECG-gated CT scanning has important clinical value in the diagnosis of complex CHD in children, complementing and extending the findings of TTE. PMID:27788237

  6. Application of Prospective ECG-Gated High-Pitch 128-Slice Dual-Source CT Angiography in the Diagnosis of Congenital Extracardiac Vascular Anomalies in Infants and Children

    PubMed Central

    Wang, Ximing; Duan, Yanhua; Xu, Wenjian; Li, Haiou; Cao, Ting; Liu, Xuejun; Ji, Xiaopeng; Cheng, Zhaoping; Wang, Anbiao

    2014-01-01

    Purpose To investigate the value of prospective ECG-gated high-pitch 128-slice dual-source CT (DSCT) angiography in the diagnosis of congenital extracardiac vascular anomalies in infants and children in comparison with transthoracic echocardiography (TTE). Methods Eighty consecutive infants or children clinically diagnosed of congenital heart disease and suspected with extracardiac vascular anomaly were enrolled, and 75 patients were finally included in this prospective study. All patients underwent prospective ECG-gated high-pitch DSCT angiography after TTE with an interval of 1–7 days. The diagnostic accuracy and sensitivity of high-pitch DSCT angiography and TTE were compared according to the surgical/CCA findings. The image quality of DSCT was assessed using a five-point scale. The effective radiation dose (ED) was calculated. Results A total of 17 congenital heart diseases and 162 separate extracardiac vascular anomalies were confirmed by surgical/CCA findings in 75 patients. The diagnostic accuracy of high-pitch DSCT angiography and TTE was 99.67% and 97.89%, respectively. The sensitivity of high-pitch DSCT angiography and TTE was 97.53% and 79.62%, respectively. There was significant difference regarding to the diagnostic accuracy and the sensitivity between high-pitch DSCT angiography and TTE (χ2 = 23.561 and 28.013, P<0.05). The agreement on the image quality scoring of DSCT between the two observers was excellent (κ = 0.81), and the mean score of image quality was 4.1±0.7. The mean ED of DSCT was 0.29±0.08 mSv. Conclusions Prospective ECG-gated high-pitch 128-slice DSCT angiography with low radiation dose and high diagnostic accuracy has higher sensitivity compared to TTE in the detection of congenital extracardiac vascular anomalies in infants and children. PMID:25546178

  7. CT angiography of neonates and infants: comparison of radiation dose and image quality of target mode prospectively ECG-gated 320-MDCT and ungated helical 64-MDCT.

    PubMed

    Jadhav, Siddharth P; Golriz, Farahnaz; Atweh, Lamya A; Zhang, Wei; Krishnamurthy, Rajesh

    2015-02-01

    OBJECTIVE. The purpose of this study was to evaluate the radiation dose and image quality of target mode prospectively ECG-gated volumetric CT angiography (CTA) performed with a 320-MDCT scanner compared with the radiation dose and image quality of ungated helical CTA performed with a 64-MDCT scanner. MATERIALS AND METHODS. An experience with CTA for cardiovascular indications in neonates and infants 0-6 months old was retrospectively assessed. Radiation doses and quantitative and qualitative image quality scores of 28 CTA examinations performed with a 320-MDCT scanner and volumetric target mode prospective ECG gating plus iterative reconstruction (target mode) were compared with the doses and scores of 28 CTA examinations performed with a 64-MDCT scanner and ungated helical scanning plus filtered back projection reconstruction (ungated mode). All target mode studies were performed during free breathing. Seven ungated CTA examinations (25%) were performed with general endotracheal anesthesia. The findings of 17 preoperative CTA examinations performed in target mode were also compared with surgical reports for evaluation of diagnostic accuracy. RESULTS. All studies performed with target mode technique were diagnostic for the main clinical indication. Effective doses were significantly lower in the target mode group (0.51 ± 0.19 mSv) compared with the ungated mode group (4.8 ± 1.4 mSv) (p < 0.0001). Quantitative analysis revealed no statistically significant difference between the two groups with respect to signal-to-noise ratio (of pulmonary artery and aorta) and contrast-to-noise ratio. Subjective image quality was significantly better with target mode than with ungated mode (p < 0.0001). CONCLUSION. Target mode prospectively ECG-gated volumetric scanning with iterative reconstruction performed with a 320-MDCT scanner has several benefits in cardiovascular imaging of neonates and infants, including low radiation dose, improved image quality, high diagnostic

  8. Evaluation of exposure dose reduction in multislice CT coronary angiography (MS-CTA) with prospective ECG-gated helical scan

    NASA Astrophysics Data System (ADS)

    Ota, Takamasa; Tsuyuki, Masaharu; Okumura, Miwa; Sano, Tomonari; Kondo, Takeshi; Takase, Shinichi

    2008-03-01

    A novel low-dose ECG-gated helical scan method to investigate coronary artery diseases was developed. This method uses a high pitch for scanning (based on the patient's heart rate) and X-rays are generated only during the optimal cardiac phases. The dose reduction was obtained using a two-level approach: 1) To use a 64-slice CT scanner (Aquilion, Toshiba, Otawara, Tochigi, Japan) with a scan speed of 0.35 s/rot. to helically scan the heart at a high pitch based on the patient's heart rate. By changing the pitch from the conventional 0.175 to 0.271 for a heart rate of 60 bpm, the exposure dose was reduced to 65%. 2) To employ tube current gating that predicts the timing of optimal cardiac phases from the previous cardiac cycle and generates X-rays only during the required cardiac phases. The combination of high speed scanning with a high pitch and appropriate X-ray generation only in the cardiac phases from 60% to 90% allows the exposure dose to be reduced to 5.6 mSv for patients with a heart rate lower than 65 bpm. This is a dose reduction of approximately 70% compared to the conventional scanning method recommended by the manufacturer when segmental reconstruction is considered. This low-dose protocol seamlessly allows for wide scan ranges (e.g., aortic dissection) with the benefits of ECG-gated helical scanning: smooth continuity for longitudinal direction and utilization of data from all cardiac cycles.

  9. The feasibility of sub-millisievert coronary CT angiography with low tube voltage, prospective ECG gating, and a knowledge-based iterative model reconstruction algorithm.

    PubMed

    Park, Chul Hwan; Lee, Joohee; Oh, Chisuk; Han, Kyung Hwa; Kim, Tae Hoon

    2015-12-01

    We evaluated the feasibility of sub-millisievert (mSv) coronary CT angiography (CCTA) using low tube voltage, prospective ECG gating, and a knowledge-based iterative model reconstruction algorithm. Twenty-four non-obese healthy subjects (M:F 13:11; mean age 50.2 ± 7.8 years) were enrolled. Three sets of CT images were reconstructed using three different reconstruction methods: filtered back projection (FBP), iterative reconstruction (IR), and knowledge-based iterative model reconstruction (IMR). The scanning parameters were as follows: step-and-shoot axial scanning, 80 kVp, and 200 mAs. On the three sets of CT images, the attenuation and image noise values were measured at the aortic root. The signal-to-noise ratio (SNR) and the contrast-to-noise ratio (CNR) were calculated at the proximal right coronary artery and the left main coronary artery. The qualitative image quality of the CCTA with IMR was assessed using a 4-point grading scale (grade 1, poor; grade 4, excellent). The mean radiation dose of the CCTA was 0.89 ± 0.09 mSv. The attenuation values with IMR were not different from those of other reconstruction methods. The image noise with IMR was significantly lower than with IR and FBP. Compared to FBP, the noise reduction rate of IMR was 69 %. The SNR and CNR of CCTA with IMR were significantly higher than with FBP or IR. On the qualitative analysis with IMR, all included segments were diagnostic (grades 2, 3, and 4), and the mean image quality score was 3.6 ± 0.6. In conclusion, CCTA with low tube voltage, prospective ECG gating, and an IMR algorithm might be a feasible method that allows for sub-millisievert radiation doses and good image quality when used with non-obese subjects. PMID:26521066

  10. Iodinated Contrast Opacification Gradients in Normal Coronary Arteries Imaged with Prospectively ECG-Gated Single Heart Beat 320-Detector Row Computed Tomography

    PubMed Central

    Steigner, Michael L.; Mitsouras, Dimitrios; Whitmore, Amanda G.; Otero, Hansel J.; Wang, Chunliang; Buckley, Orla; Levit, Noah A.; Hussain, Alia Z.; Cai, Tianxi; Mather, Richard T.; Smedby, Örjan; DiCarli, Marcelo F.; Rybicki, Frank J.

    2011-01-01

    Background To define and evaluate coronary contrast opacification gradients using prospectively ECG-gated single heart beat 320-detector row coronary angiography (CTA). Methods and Results Thirty-six patients with normal coronary arteries determined by 320 × 0.5 mm detector row coronary CTA were retrospectively evaluated with customized image post-processing software to measure Hounsfield Units (HU) at 1 mm intervals orthogonal to the artery center line. Linear regression determined correlation between mean HU and distance from the coronary ostium (regression slope defined as the distance gradient Gd), lumen cross-sectional area (Ga), and lumen short axis diameter (Gs). For each gradient, differences between the three coronary arteries were analyzed with ANOVA. Linear regression determined correlations between measured gradients, heart rate, body-mass index (BMI), and cardiac phase. To determine feasibility in lesions, all three gradients were evaluated in 22 consecutive patients with left anterior descending artery lesions greater than or equal to 50% stenosis. For all 3 coronary arteries in all patients, the gradients Ga and Gs were significantly different from zero (p<0.0001), highly linear (Pearson r values 0.77-0.84), and had no significant difference between the LAD, LCx, and RCA (p>0.503). The distance gradient Gd demonstrated nonlinearities in a small number of vessels and was significantly smaller in the RCA when compared to the left coronary system (p<0.001). Gradient variations between cardiac phases, heart rates, BMI, and readers were low. Gradients in patients with lesions were significantly different (p<0.021) than in patients considered normal by CTA. Conclusions Measurement of contrast opacification gradients from temporally uniform coronary CTA demonstrates feasibility and reproducibility in patients with normal coronary arteries. For all patients the gradients defined with respect to the coronary lumen cross-sectional area and short axis

  11. Prospective versus retrospective ECG-gated 64-detector coronary CT angiography for evaluation of coronary artery bypass graft patency: comparison of image quality, radiation dose and diagnostic accuracy.

    PubMed

    Lee, Jae Hwan; Chun, Eun Ju; Choi, Sang Il; Vembar, Mani; Lim, Cheong; Park, Kay-Hyun; Choi, Dong-Ju

    2011-06-01

    We aimed to evaluate image quality, radiation dose and diagnostic accuracy of coronary CT angiography (CCTA) with a prospectively gated transverse-axial scan (PGT) compared with a retrospectively gated helical scan (RGH), using a 64-slice scanner in patients who underwent coronary artery bypass graft (CABG). Of the 131 consecutive patients that underwent CABG using 64-slice multidetector row computed tomography during 2008, patients with heart rate (HR) of <75 beats/minute (bpm), and HR variation <10 bpm were included in the study. PGT was performed on 39 patients with 93 grafts, with RGH performed on 43 patients with 102 grafts. Image quality (1: excellent-4: poor) and estimated radiation dose were compared between the two groups. Of these, a total of 64 segments in 26 patients were subjected to invasive coronary angiography (ICA) for clinical reasons. Diagnostic accuracy of CCTA for evaluation of graft was performed between the two groups with ICA as a reference standard in terms of significant stenosis (≥ 50% of luminal stenosis). The image quality was not statistically different in the two groups. Mean effective radiation dose was 6.5 mSv in PGT-group, which was significantly lower than that in the RGH-group (21.2 mSv; P < 0.001). There was no statistically significant difference in diagnostic accuracy between the two groups (PGT-group versus RGH-group; 93.1% versus 91.4%). PGT can achieve dose reductions of up to 70% compared to RGH while maintaining image quality and high diagnostic accuracy in patients undergoing CABG. PMID:21678128

  12. Performance characterstics of a commerical ECG gate

    SciTech Connect

    Graham, M.; Cavailloles, F.; Ritchie, J.L.; Williams, D.L.; Hamilton, G.W.

    1980-04-01

    A commercial ECG gate was tested to evaluate its ability to predict accurately the time of end-systole. The predicted times followed the manufacturer's specifications quite well. These times were compared with the actual times of end-systole as determined by computer-derived left-ventricular time-activity curves using Tc-99m-labeled red blood cells. Although there was moderate scatter, the predicted times of end-systole correlated well with the actual time (n = 59, r = 0.829). If the left-ventricular ejection fraction was calculated using the predicted time of end-systole, the error would be 0.03, or less, for 95% of the subjects.

  13. A method for the determination of ECG gate signal delays

    SciTech Connect

    Wery, R.; Hill, J.; Dworkin, H.J.

    1981-06-01

    A simple device using a rotating radioactive source was developed to monitor the presence of a delay between the patient's R wave and the gate signal being sent to the computer. Three commercial ECG gates were tested and significant delays were found in two of them. Identical patient data evaluated using ECG gates with and without significant delays produced calculated left-ventricular ejection fractions of 0.05 and 0.64, respectively.

  14. Measurement of ventricular function by ECG gating during atrial fibrillation

    SciTech Connect

    Bacharach, S.L.; Green, M.V.; Bonow, R.O.; Findley, S.L.; Ostrow, H.G.; Johnston, G.S.

    1981-03-01

    The assumptions necessary to perform ECG-gated cardiac studies are seemingly not valid for patients in atrial fibrillation (AF). To evaluate the effect of AF on equilibrium gated scintigraphy, beat-by-beat measurements of left-ventricular function were made on seven subjects in AF (mean heart rate 64 bpm), using a high-efficiency nonimaging detector. The parameters evaluated were ejection fraction (EF), time to end-systole (TES), peak rates of ejection and filling (PER,PFR), and their times of occurrence (TPER, TPFR). By averaging together single-beat values of EF, PER, etc., it was possible to determine the true mean values of these parameters. The single-beam mean values were compared with the corresponding parameters calculated from one ECG-gated time-activity curve (TAC) obtained by superimposing all the single-beat TACs irrespective of their length. For this population with slow heart rates, we find that the values for EF, etc., produced from ECG-gated time-activity curves, are very similar to those obtained from the single-beat data. Thus use of ECG gating at low heart rates may allow reliable estimation of average cardiac function even in subjects with AF.

  15. ECG gated NMR-CT for cardiovascular diseases

    SciTech Connect

    Nishikawa, J.; Ohtake, T.; Machida, K.; Iio, M.; Yoshimoto, N.; Sugimoto, T.

    1985-05-01

    The authors have been applying ECG gated NMR-CT to mainly patients with myocardial infarction (MI), and hypertrophic cardiomyopathy (HCM). Thirteen patients with MI, 8 with HCM and 5 without any heart diseases were studied by ECG gated NMR imaging (spin-echo technique, TR: depends on patient heart rate, TE: 35 and 70 msec.) with 0.35 T superconducting magnet. On NMR images (MRI), the authors examined the wall thickness, wall motion and T/sub 2/ relaxation time in the area of diseased myocardium. The lesions of old MI were depicted as the area of thin wall and T/sub 2/ relaxation time of those lesions were similar to the area of non-infarcted myocardium. The lesions of recent MI (up to 3.5 months from the recent attack) were shown as the same wall thickness as the non-infarcted myocardium and the area of prolonged T/sub 2/ relaxation time compared with that of non-infarcted myocardium. MRI demonstrated diffusely thick myocardium in all patients with HCM. T/sub 2/ relaxation time of the areas of HCM was almost the same as that of normal myocardium, and it's difference among each ventricular wall in patients with HCM was not statistically significant. The authors conclude that ECG gated NMR-CT offers 3-D morphological information of the heart without any contrast material nor radioisotopes. ECG gated MRI provides the useful informations to diagnose MI, especially in the differential diagnosis between old and recent MI.

  16. Magnitude and effects of x-ray scatter in a 256-slice CT scanner

    SciTech Connect

    Endo, Masahiro; Mori, Shinichiro; Tsunoo, Takanori; Miyazaki, Hiroaki

    2006-09-15

    We developed a prototype 256-slice CT scanner that employs continuous rotation of a cone-beam with a larger cone angle than conventional multidetector CTs (MDCT) to ensure a wide field of view. However, a larger cone angle may result in image deterioration due to increased x-ray scatter. Scattered radiation causes the detected signals to deviate from the true measurement of primary x-ray intensity and may result in artifacts (e.g., cupping and streak artifacts), quantitative inaccuracy in reconstructed CT number, and degradation of contrast-to-noise ratio (CNR). To reduce the effects of scatter, the 256-slice scanner incorporates an antiscatter collimator. Here, we estimated the magnitude of x-ray scatter in the prototype 256-slice CT scanner under clinical scan conditions and quantified the effects of this scatter on CT number accuracy, image noise, uniformity, and low contrast detectability. Although most experiments were performed with the antiscatter collimator, we also estimated the magnitude of x-ray scatter without the collimator to evaluate the scatter rejection efficiency of the collimator. The scatter-to-primary energy fluence ratio (SPR) without the collimator increased as cone angle increased, with estimated values of 49.7% for a 138 mm beam width with a phantom of 200 mm diameter, and 78.5% for a 320 mm diameter phantom. Estimated SPR was drastically decreased with the collimator, with an SPR reduction rate (ratio of SPR with and without the collimator) of 12.7% and 16.8% for the 200 and 320 mm diameter phantoms, respectively. The reduction in x-ray scatter by the collimator resulted in a considerable reduction in scatter effects. The measured uniformity was good and was independent of scatter amount. Although scatter still affected CT number accuracy, this could be corrected by rescaling. Further, although the CNR was decreased, in theory at least, the change was so subtle that it had no substantial effect on low-contrast detectability.

  17. Diagnostic quality of time-averaged ECG-gated CT data

    NASA Astrophysics Data System (ADS)

    Klein, Almar; Oostveen, Luuk J.; Greuter, Marcel J. W.; Hoogeveen, Yvonne; Schultze Kool, Leo J.; Slump, Cornelis H.; Renema, W. Klaas Jan

    2009-02-01

    Purpose: ECG-gated CTA allows visualization of the aneurysm and stentgraft during the different phases of the cardiac cycle, although with a lower SNR per cardiac phase than without ECG gating using the same dose. In our institution, abdominal aortic aneurysm (AAA) is evaluated using non-ECG-gated CTA. Some common CT scanners cannot reconstruct a non-gated volume from ECG-gated acquired data. In order to obtain the same diagnostic image quality, we propose offline temporal averaging of the ECG-gated data. This process, though straightforward, is fundamentally different from taking a non-gated scan, and its result will certainly differ as well. The purpose of this study is to quantitatively investigate how good off-line averaging approximates a non-gated scan. Method: Non-gated and ECG-gated CT scans have been performed on a phantom (Catphan 500). Afterwards the phases of the ECG-gated CTA data were averaged to create a third dataset. The three sets are compared with respect to noise properties (NPS) and frequency response (MTF). To study motion artifacts identical scans were acquired on a programmable dynamic phantom. Results and Conclusions: The experiments show that the spatial frequency content is not affected by the averaging process. The minor differences observed for the noise properties and motion artifacts are in favor of the averaged data. Therefore the averaged ECG-gated phases can be used for diagnosis. This enables the use of ECG-gating for research on stentgrafts in AAA, without impairing clinical patient care.

  18. The influence of novel CT reconstruction technique and ECG-gated technique on image quality and patient dose of cardiac computed tomography.

    PubMed

    Dyakov, I; Stoinova, V; Groudeva, V; Vassileva, J

    2015-07-01

    The aim of the present study was to compare image quality and patient dose in cardiac computed tomography angiography (CTA) in terms of volume computed tomography dose index (CTDI vol), dose length product (DLP) and effective dose, when changing from filtered back projection (FBP) to adaptive iterative dose reduction (AIDR) reconstruction techniques. Further aim was to implement prospective electrocardiogram (ECG) gating for patient dose reduction. The study was performed with Aquilion ONE 320-row CT of Toshiba Medical Systems. Analysis of cardiac CT protocols was performed before and after integration of the new software. The AIDR technique showed more than 50 % reduction in CTDIvol values and 57 % in effective dose. The subjective evaluation of clinical images confirmed the adequate image quality acquired by the AIDR technique. The preliminary results indicated significant dose reduction when using prospective ECG gating by keeping the adequate diagnostic quality of clinical images. PMID:25836680

  19. ECG gated NMR-CT for cardiovascular diseases

    SciTech Connect

    Nishikawa, J.; Machida, K.; Iio, M.; Yoshimoto, N.; Sugimoto, T.; Kawaguchi, H.; Mano, H.

    1984-01-01

    The authors applied NMR-CT to cardiac study with ECG gated technique to evaluate the left ventricular (LV) function and compared it with cardiovascular nuclear medicine study (NM). The NMR-CT machine has resistive air-core magnet with 0.15 Tesla. The saturation recovery image or inversion recovery image were obtained as 256 x 256 matrix and 15 mm in thickness. The study population was ten patients who were evaluated both by NMR image and by NM performed within one week interval. The heart muscle was able to be visualized without any contrast material nor radioisotopes in inversion recovery images, whereas saturation recovery images failed to separate heart muscle from blood pool. The wall motions of LV in both methods were well correlated except for inferior wall. The values of ejection fraction in NMR image were moderately low, but two modalities showed satisfactory correlation (r=0.85). The region of myocardial infarction was revealed as wall thinning and/or wall motion abnormality. It is still preliminary to draw a conclusion, however, it can be said that in the evaluation of LV function, method by NMR might be of equal value to those of NM. It can be certain that eventually gated NMR-CT will become more effective method for various aspects of cardiovascular evaluation.

  20. Coronary lesion complexity assessed by SYNTAX score in 256-slice dual-source MDCT angiography

    PubMed Central

    Yüceler, Zeyneb; Kantarcı, Mecit; Tanboğa, İbrahim Halil; Sade, Recep; Kızrak, Yeşim; Pirimoğlu, Berhan; Bayraktutan, Ümmügülsüm; Oğul, Hayri; Aksakal, Enbiya

    2016-01-01

    PURPOSE The SYNTAX Score (SS) has an important role in grading the complexity of coronary artery disease (CAD) in patients undergoing revascularization. Noninvasive determination of SS prior to invasive coronary angiography (ICA) might optimize patient management. We aimed to evaluate the agreement between ICA and multidetector computed tomography (MDCT) while testing the diagnostic effectiveness of SS-MDCT. METHODS Our study included 108 consecutive patients who underwent both MDCT angiography with a 256-slice dual-source MDCT system and ICA within 14±3 days. SS was calculated for both ICA and MDCT coronary angiography. Spearman’s rank correlation coefficient was used to evaluate the association of SS-MDCT with SS-ICA, and Bland-Altman analysis was performed. RESULTS The degree of agreement between SS-ICA and SS-MDCT was moderate. The mean SS-MDCT was 14.5, whereas the mean SS-ICA was 15.9. After dividing SS into three groups (high [≥33], intermediate [23–32], and low [≤22] subgroups), agreement analysis was repeated. There was a significant correlation between SS-MDCT and SS-ICA in the low SS group (r=0.63, P = 0.043) but no significant correlation in the high SS group (r=0.036, P = 0.677). The inter-test agreement analysis showed at least moderate agreement, whereas thrombotic lesions and the type of bifurcation lesion showed fair agreement. CONCLUSION The calculation of SS-MDCT by adapting SS-ICA parameters achieved nearly the same degree of precision as SS-ICA and was better than SS-ICA, especially in the low SS group. PMID:27328718

  1. Non-ECG-Gated Myocardial Perfusion MRI Using Continuous Magnetization-Driven Radial Sampling

    PubMed Central

    Sharif, Behzad; Dharmakumar, Rohan; Arsanjani, Reza; Thomson, Louise; Merz, C. Noel Bairey; Berman, Daniel S.; Li, Debiao

    2014-01-01

    Purpose Establishing a high-resolution non-ECG-gated first-pass perfusion (FPP) cardiac MRI technique may improve accessibility and diagnostic capability of FPP imaging. We propose a non-ECG-gated FPP imaging technique using continuous magnetization-driven golden-angle radial acquisition. The main purpose of this preliminary study is to evaluate whether, in the simple case of single-slice 2D imaging, adequate myocardial contrast can be obtained for accurate visualization of hypoperfused territories in the setting of myocardial ischemia. Methods A T1-weighted pulse sequence with continuous golden-angle radial sampling was developed for non-ECG-gated FPP imaging. A sliding-window scheme with no temporal acceleration was used to reconstruct 8 frames/second. Canines were imaged at 3T with and without coronary stenosis using the proposed scheme and a conventional magnetization-prepared ECG-gated FPP method. Results Our studies showed that the proposed non-ECG-gated method is capable of generating high-resolution (1.7×1.7×6 mm3) artifact-free FPP images of a single slice at high heart rates (92±21 beats/minute), while matching the performance of conventional FPP imaging in terms of hypoperfused-to-normal myocardial contrast-to-noise ratio (proposed: 5.18±0.70, conventional: 4.88±0.43). Furthermore, the detected perfusion defect areas were consistent with the conventional FPP images. Conclusion Non-ECG-gated FPP imaging using optimized continuous golden-angle radial acquisition achieves desirable image quality (i.e., adequate myocardial contrast, high spatial resolution, and minimal artifacts) in the setting of ischemia. PMID:24443160

  2. Evaluation of radiation dose of triple rule-out coronary angiography protocols with different scan length using 256-slice CT

    NASA Astrophysics Data System (ADS)

    Tsai, Chia-Jung; Lee, Jason J. S.; Chen, Liang-Kuang; Mok, Greta S. P.; Hsu, Shih-Ming; Wu, Tung-Hsin

    2011-10-01

    Triple rule-out coronary CT angiography (TRO-CTA) is a new approach for providing noninvasive visualization of coronary arteries with simultaneous evaluation of pulmonary arteries, thoracic aorta and other intrathoracic structures. The increasing use of TRO-CTA examination with longer scan length is associated with the concerns about radiation dose and their corresponding cancer risk. The purpose of this study is to evaluate organ dose and effective dose for the TRO-CTA examination with 2 scan lengths: TRO std and TRO ext, using 256-slice CT. TRO-CTA examinations were performed on a 256-slice CT scanner without ECG-based tube current modulation. Absorbed organ doses were measured using an anthropomorphic phantom and thermal-luminance dosimeters (TLDs). Effective dose was determined by taking a sum of the measured absorbed organ doses multiplied with the tissue weighting factor based on ICRP-103, and compared to that calculated using the dose-length product (DLP) method. We obtained high organ doses in the thyroid, esophagus, breast, heart and lung in both TRO-CTA protocols. Effective doses of the TRO std and TRO ext protocols with the phantom method were 26.37 and 42.49 mSv, while those with the DLP method were 19.68 and 38.96 mSv, respectively. Our quantitative dose information establishes a relationship between radiation dose and scanning length, and can provide a practical guidance to best clinical practice.

  3. Effect of heart rate on the diagnostic accuracy of 256-slice computed tomography angiography in the detection of coronary artery stenosis: ROC curve analysis

    PubMed Central

    WANG, GANG; WU, YIFEN; ZHANG, ZHENTAO; ZHENG, XIAOLIN; ZHANG, YULAN; LIANG, MANQIU; YUAN, HUANCHU; SHEN, HAIPING; LI, DEWEI

    2016-01-01

    The aim of the present study was to investigate the effect of heart rate (HR) on the diagnostic accuracy of 256-slice computed tomography angiography (CTA) in the detection of coronary artery stenosis. Coronary imaging was performed using a Philips 256-slice spiral CT, and receiver operating characteristic (ROC) curve analysis was conducted to evaluate the diagnostic value of 256-slice CTA in coronary artery stenosis. The HR of the research subjects in the study was within a certain range (39–107 bpm). One hundred patients suspected of coronary heart disease underwent 256-slice CTA examination. The cases were divided into three groups: Low HR (HR <75 bpm), moderate HR (75≤ HR <90 bpm) and high HR (HR ≥90 bpm). For the three groups, two observers independently assessed the image quality for all coronary segments on a four-point ordinal scale. An image quality of grades 1–3 was considered diagnostic, while grade 4 was non-diagnostic. A total of 97.76% of the images were diagnostic in the low-HR group, 96.86% in the moderate-HR group and 95.80% in the high-HR group. According to the ROC curve analysis, the specificity of CTA in diagnosing coronary artery stenosis was 98.40, 96.00 and 97.60% in the low-, moderate- and high-HR groups, respectively. In conclusion, 256-slice coronary CTA can be used to clearly show the main segments of the coronary artery and to effectively diagnose coronary artery stenosis. Within the range of HRs investigated, HR was found to have no significant effect on the diagnostic accuracy of 256-slice coronary CTA for coronary artery stenosis. PMID:27168831

  4. ECG gating of thallium-201 myocardial images: effect on detection of ischemic heart disease

    SciTech Connect

    McKillop, J.H.; Fawcett, H.D.; Baumert, J.E.; McDougall, I.R.; DeBusk, R.F.; Harrison, D.C.; Goris, M.L.

    1981-03-01

    Using the angiographic findings as the standard, we have examined the sensitivity and specificity of ECG-gated static thallium-201 myocardial images in 54 patients undergoing selective coronary arteriography. Gated and nongated images, each in anterior, 45 LAO, and 65 LAO projections, were processed by interpolative background subtraction. They were then analyzed separately by four independent observers who were unaware of patient identity, the results of coronary arteriography, and which studies were gated or nonongated. No significant differences were observed between the gated and ngated images regarding sensitivity or specificity, the detection rate for reversible myocardial ischmia, the accuracy of prediction of arteriographic extent of disease, or the degree of inter-or intraobserver variability. We conclude that ECG-gated acquisition of Tl-201 images does not produce any significant advantages, at least when interpolative background subtraction is used.

  5. Impact of Cardiac Arrhythmia on Velocity Quantification by ECG gated Phase Contrast MRI

    PubMed Central

    Markl, Michael; Fluckiger, Jacob; Lee, Daniel C.; Ng, Jason; Goldberger, Jeffrey J.

    2014-01-01

    Objective To systematically investigate the impact of beat-to-beat variations on ECG gated multi-beat flow imaging with phase contrast (PC) MRI based on real time in-vivo TEE data in patients with known arrhythmia. Methods Real-time 2D Doppler transesophageal echocardiography (TEE) was performed in five patients with atrial fibrillation (4 male, age=64±8.7 years). TEE data provided real-time left atrial (LA) and left ventricular (LV) flow velocities in consecutive cardiac cycles with different RR-interval durations. PC-MRI acquisitions were simulated from the TEE velocity measures by constructing time-resolved k-space data for segmented sampling schemes typically used for ECG gated 2D PC MRI. Each simulation was repeated 100 times to minimize effects from data that may be weighted to a particular beat in the center of k-space. The resulting LA and LV velocities were compared to the average TEE velocities and data from individual cardiac cycles. Results Despite beat-to-beat variations velocities in TEE data, ECG gated flow imaging with MRI could reproduce persistent average LA and LV mean velocities within 7.0–7.4% compared to TEE. Conclusions PC-MRI velocity measurements in patients with varying R-R interval durations are not significantly different from time-averaged real-time velocity data for a typical segmented k-space data acquisition schemes. Though beat-to-beat variations in atrial velocities that were observed with TEE cannot be detected with ECG gated multi-beat PC MRI, it can reliably assess average flow patterns across multiple beats PMID:25978593

  6. Residual motion compensation in ECG-gated interventional cardiac vasculature reconstruction

    NASA Astrophysics Data System (ADS)

    Schwemmer, C.; Rohkohl, C.; Lauritsch, G.; Müller, K.; Hornegger, J.

    2013-06-01

    Three-dimensional reconstruction of cardiac vasculature from angiographic C-arm CT (rotational angiography) data is a major challenge. Motion artefacts corrupt image quality, reducing usability for diagnosis and guidance. Many state-of-the-art approaches depend on retrospective ECG-gating of projection data for image reconstruction. A trade-off has to be made regarding the size of the ECG-gating window. A large temporal window is desirable to avoid undersampling. However, residual motion will occur in a large window, causing motion artefacts. We present an algorithm to correct for residual motion. Our approach is based on a deformable 2D-2D registration between the forward projection of an initial, ECG-gated reconstruction, and the original projection data. The approach is fully automatic and does not require any complex segmentation of vasculature, or landmarks. The estimated motion is compensated for during the backprojection step of a subsequent reconstruction. We evaluated the method using the publicly available CAVAREV platform and on six human clinical datasets. We found a better visibility of structure, reduced motion artefacts, and increased sharpness of the vessels in the compensated reconstructions compared to the initial reconstructions. At the time of writing, our algorithm outperforms the leading result of the CAVAREV ranking list. For the clinical datasets, we found an average reduction of motion artefacts by 13 ± 6%. Vessel sharpness was improved by 25 ± 12% on average.

  7. ECG-gated emission computed tomography of the cardiac blood pool

    SciTech Connect

    Moore, M.L.; Murphy, P.H.; Burdine, J.A.

    1980-01-01

    ECG-gated cross-sectional images of the cardiac blood pool were produced using a specially constructed emission computed tomographic scanner. A pair of large-field-of-view cameras were mounted in opposition in a gantry that rotates 360/sup 0/ about the patient. The coordinates of each detected event, the output of a physiological synchronizer, and the position of the camera heads were input to a dedicated minicomputer which was used to produce the images. Display as a movie permitted evaluation of regional and global wall motion in cross section without the disadvantages of superimposed blood pools as obtained in nontomographic views.

  8. Three dimensional quantification of left ventricular wall motion by ECG-gated blood pool emission tomography

    SciTech Connect

    Underwood, S.R.; Walton, S.; Laming, P.J.; Jarritt, P.H.; Ell, P.J.; Emanuel, R.W.; Swanton, R.H.

    1985-05-01

    ECG-gated blood pool emission tomography is a relatively new technique, and this study establishes a simple method for displaying the three dimensional data obtained, determines a normal range for ejection fraction in all regions of the left ventricle, and compares wall motion in abnormal subjects with that determined by X-ray contrast ventriculography. The short axis sections dividing the ventricle in slices from apex to base, were used to calculate ejection fraction for all parts of the ventricle and the results were plotted on a single colour coded circular image. The apex was represented in the centre, the base around the circumference, and all other parts of the ventricle were represented in between. The image was divided into 15 segments, and normal segmental ejection fraction was defined as within two standard deviations of the mean in a group of 10 normal subjects. In 25 subjects with coronary artery disease, motion of the anterior, apical, and inferior walls agreed in every case with the right anterior oblique contrast ventriculogram, but in 12 of these, the three dimensional ejection fraction image showed abnormal septal motion, and in a further 3, abnormal lateral wall motion in addition. In the 12 subjects there was disease of the left anterior descending coronary artery, and in the further 3 there was left circumflex disease. ECG-gated blood pool emission tomography thus provides an accurate quantitative assessment of left ventricular wall motion in three dimensions, and has significant advantages over conventional planar techniques.

  9. ECG-gated HYPR reconstruction for undersampled CT myocardial perfusion imaging

    NASA Astrophysics Data System (ADS)

    Speidel, Michael A.; Van Lysel, Michael S.; Reeder, Scott B.; Supanich, Mark; Nett, Brian E.; Zambelli, Joseph; Chang, Su Min; Hsieh, Jiang; Chen, Guang-Hong; Mistretta, Charles A.

    2007-03-01

    In this study we develop a novel ECG-gated method of HYPR (HighlY constrained backPRojection) CT reconstruction for low-dose myocardial perfusion imaging and present its first application in a porcine model. HYPR is a method of reconstructing time-resolved images from view-undersampled projection data. Scanning and reconstruction techniques were explored using x-ray projections from a 50 sec contrast-enhanced axial scan of a 47 kg swine on a 64-slice MDCT system. Scans were generated with view undersampling factors from 2 to 10. A HYPR reconstruction algorithm was developed in which a fully-sampled composite image is generated from views collected from multiple cardiac cycles within a diastolic window. A time frame image for a heartbeat was produced by modifying the composite with projections from the cycle of interest. Heart rate variations were handled by automatically selecting cardiac window size and number of cycles per composite within defined limits. Cardiac window size averaged 35% of the R-R interval for 2x undersampling and increased to 64% R-R using 10x undersampling. The selected window size and cycles per composite was sensitive to synchrony between heart rate, gantry rate, and the view undersampling pattern. Temporal dynamics and perfusion metrics measured in conventional short-scan (FBP) images were well-reproduced in the undersampled HYPR time series. Mean transit times determined from HYPR myocardial time-density curves agreed to within 8% with the FBP results. The results indicate potential for an order of magnitude reduction in dose requirement per image in cardiac perfusion CT via undersampled scanning and ECG-gated HYPR reconstruction.

  10. [ECG-gated bypass CT angiography--application in imaging arterial bypasses].

    PubMed

    Wintersperger, B J; Bastarrika, G; Nikolaou, K; Rist, C; Huber, A; Knez, A; Reiser, M F; Becker, C R; Vicol, C

    2004-02-01

    Nowadays coronary artery bypass grafting is increasingly performed using arterial grafts. Purpose of the study was the evaluation of a appropriate 16 detector-row CT angiography protocol in patients after predominantly arterial bypass grafting. Fourteen patients after bypass grafting were including into the study and CT angiography carried out in the early postoperative period using a 16 detector-row CT system. To reduce cardiac pulsation artifacts data acquisition was implemented using ECG-gating algorithms. Overall 43 grafts (37 arterial, 6 venous) were examined. In 13 patients surgery had been performed using composite grafts with T or TY configuration. The mean heart rate was 74.1 bpm and showed a negative correlation to the image quality (r=-0.65; p=0.01). However, all data sets were diagnostic. Contrast injection protocol allowed for a homogeneous opacification throughout the vessels of interest. All non-delineationable grafts (5) showed a close proximity to the heart (T or Y grafts). Cardiac surgery is increasingly focusing on arterial revascularisation in bypass grafting and therefore leading to new demands for non-invasive bypass graft imaging. 16 detector-row CT allows a reliable visualization of even composite arterial grafts. However, for detection of grafts in the proximity of the heart a reduction of the heart rate (<65-70) still seems to be necessary. PMID:14991132

  11. A segmentation method for stentgrafts in the abdominal aorta from ECG-gated CTA data

    NASA Astrophysics Data System (ADS)

    Klein, Almar; Renema, W. KlaasJan; Oostveen, Luuk J.; Schultze Kool, Leo J.; Slump, Cornelis H.

    2008-03-01

    Endovascular aortic replacement (EVAR) is an established technique, which uses stentgrafts to treat aortic aneurysms in patients at risk of aneurysm rupture. The long-term durability of a stentgraft is affected by the stresses and hemodynamic forces applied to it, and may be reflected by the movements of the stentgraft itself during the cardiac cycle. A conventional CT scan (which results in a 3D volume) is not able to visualize these movements. However, applying ECG-gating does provide insight in the motion of the stentgraft caused by hemodynamic forces at different phases of the cardiac cycle. The amount of data obtained is a factor of ten larger compared to conventional CT, but the radiation dose is kept similar for patient safety. This causes the data to be noisy, and streak artifacts are more common. Algorithms for automatic stentgraft detection must be able to cope with this. Segmentation of the stentgraft is performed by examining slices perpendicular to the centreline. Regions with high CT-values exist at the locations where the metallic frame penetrates the slice. These regions are well suited for detection and sub-pixel localization. Spurious points can be removed by means of a clustering algorithm, leaving only points on the contour of the stent. We compare the performance of several different point detection methods and clustering algorithms. The position of the stent's centreline is calculated by fitting a circle through these points. The proposed method can detect several stentgraft types, and is robust against noise and streak artifacts.

  12. Respiratory Motion Detection and Correction in ECG-Gated SPECT: a New Approach

    PubMed Central

    Bitarafan, Ahmad; Rajabi, Hossein; Gruy, Bernhard; Rustgou, Feridoon; Sharafi, Ali Akbar; Firoozabady, Hasan; Yaghoobi, Nahid; Malek, Hadi; Pirich, Christian; Langesteger, Werner

    2008-01-01

    .001 versus y = 0.8046x + 5.1704; r = 0.89, p < 0.001). Nineteen (19/26) patients (73.1%) showed abnormal myocardial perfusion scans with reversible regional myocardial defects; of the 19 patients, 14 (14/26) patients underwent coronary angiography. Conclusion Respiratory induced motion can be successfully corrected simultaneously with the use of ECG-gated SPECT in MPI studies using this proposed technique. Moreover, the use of ECG-gated SPECT improved image quality, especially in the inferior and septal regions that are mostly affected by diaphragmatic attenuation. However, the effect of respiratory correction depends mainly on the patient respiratory pattern and may be clinically relevant in certain cases. PMID:19039264

  13. An integrated bioimpedance—ECG gating technique for respiratory and cardiac motion compensation in cardiac PET

    NASA Astrophysics Data System (ADS)

    Koivumäki, Tuomas; Nekolla, Stephan G.; Fürst, Sebastian; Loher, Simone; Vauhkonen, Marko; Schwaiger, Markus; Hakulinen, Mikko A.

    2014-10-01

    Respiratory motion may degrade image quality in cardiac PET imaging. Since cardiac PET studies often involve cardiac gating by ECG, a separate respiratory monitoring system is required increasing the logistic complexity of the examination, in case respiratory gating is also needed. Thus, we investigated the simultaneous acquisition of both respiratory and cardiac gating signals using II limb lead mimicking electrode configuration during cardiac PET scans of 11 patients. In addition to conventional static and ECG-gated images, bioimpedance technique was utilized to generate respiratory- and dual-gated images. The ability of the bioimpedance technique to monitor intrathoracic respiratory motion was assessed estimating cardiac displacement between end-inspiration and -expiration. The relevance of dual gating was evaluated in left ventricular volume and myocardial wall thickness measurements. An average 7.6  ±  3.3 mm respiratory motion was observed in the study population. Dual gating showed a small but significant increase (4 ml, p = 0.042) in left ventricular myocardial volume compared to plain cardiac gating. In addition, a thinner myocardial wall was observed in dual-gated images (9.3  ±  1.3 mm) compared to cardiac-gated images (11.3  ±  1.3 mm, p = 0.003). This study shows the feasibility of bioimpedance measurements for dual gating in a clinical setting. The method enables simultaneous acquisition of respiratory and cardiac gating signals using a single device with standard ECG electrodes.

  14. ECG-gated blood pool tomography in the determination of left ventricular volume, ejection fraction, and wall motion

    SciTech Connect

    Underwood, S.R.; Ell, P.J.; Jarritt, P.H.; Emanuel, R.W.; Swanton, R.H.

    1984-01-01

    ECG-gated blood pool tomography promises to provide a ''gold standard'' for noninvasive measurement of left ventricular volume, ejection fraction, and wall motion. This study compares these measurements with those from planar radionuclide imaging and contrast ventriculography. End diastolic and end systolic blood pool images were acquired tomographically using an IGE400A rotating gamma camera and Star computer, and slices were reconstructed orthogonal to the long axis of the heart. Left ventricular volume was determined by summing the areas of the slices, and wall motion was determined by comparison of end diastolic and end systolic contours. In phantom experiments this provided an accurate measurement of volume (r=0.98). In 32 subjects who were either normal or who had coronary artery disease left ventricular volume (r=0.83) and ejection fraction (r=0.89) correlated well with those using a counts based planar technique. In 16 of 18 subjects who underwent right anterior oblique X-ray contrast ventriculography, tomographic wall motion agreed for anterior, apical, and inferior walls, but abnormal septal motion which was not apparent by contrast ventriculography, was seen in 12 subjects tomographically. All 12 had disease of the left anterior descending coronary artery and might have been expected to have abnormal septal motion. ECG-gated blood pool tomography can thus determine left ventricular volume and ejection fraction accurately, and provides a global description of wall motion in a way that is not possible from any single planar image.

  15. Coronary Plaque Characteristics Assessed by 256-Slice Coronary CT Angiography and Association with High-Sensitivity C-Reactive Protein in Symptomatic Patients with Type 2 Diabetes

    PubMed Central

    Zhang, Jinling; Lv, Zhehao; Zhao, Deli; Liu, Lili; Wan, Yong; Fan, Tingting; Li, Huimin; Guan, Ying; Liu, Bailu

    2016-01-01

    Little is known regarding plaque distribution, composition, and the association with inflammation in type 2 diabetes mellitus (DM2). This study aimed to assess the relationship between coronary plaque subtypes and high-sensitivity C-reactive protein levels. Coronary CTA were performed in 98 symptomatic DM2 patients and 107 non-DM2 patients using a 256-slice CT. The extent and types of plaque as well as luminal narrowing were evaluated. Patients with DM2 were more likely to have significant stenosis (>50%) with calcified plaques in at least one coronary segment (p < 0.01); the prevalence rates of diffuse calcified plaques in the DM2 and non-DM2 groups were 31.6% and 4.7%, respectively (p < 0.01). Plasma hs-CRP levels in DM2 with calcified plaques were higher compared with values obtained for the non-DM2 group (p < 0.01). In conclusion, combination of coronary CTA and hs-CRP might improve risk stratification in symptomatic DM2 patients. PMID:27579325

  16. ECG-gated blood-pool study of carotid arterial pulsation as a sign of stenosis: concise communication

    SciTech Connect

    Winston, M.A.; Cohen, S.N.

    1983-06-01

    The large elastic arteries, such as the carotids, pulsate (expand and contract) in synchrony with the heart beat. These pulsations should be reduced by significant stenosis. This hypothesis was studied in 15 men by obtaining sequential ECG-gated labeled blood-pool images of these vessels in anterior and lateral oblique views. These were computer processed by a functional program that displays each pixel with an intensity proportional to its change in activity level during the cardiac cycle. Blank areas indicated lack of pulsation and were correlated with angiographic studies. The blank skip areas were present when there was 50% or greater narrowing in arterial diameter (94% sensitivity) but were not seen in patients with normal or minimally diseased vessels (25% or less narrowing). They were present inconsistently in the four vessels with 25 to 50% narrowing.

  17. Reproducibility of aortic pulsatility measurements from ECG-gated abdominal CTA in patients with abdominal aortic aneurysms

    NASA Astrophysics Data System (ADS)

    Manduca, Armando; Fletcher, Joel G.; Wentz, Robert J.; Shields, Raymond C.; Vrtiska, Terri J.; Siddiki, Hassan; Nielson, Theresa

    2009-02-01

    Purpose: ECG-gated abdominal CT angiography with reconstruction of multiple, temporally overlapping CT angiography datasets has been proposed for measuring aortic pulsatility. The purpose of this work is to develop algorithms to segment the aorta from surrounding structures from CTA datasets across cardiac phases, calculate registered centerlines and measurements of regional aortic pulsatility in patients with AAA, and to assess the reproducibility of these measurements. Methods: ECG-gated CTA was performed with a temporal resolution of 165 ms, reconstructed to 1 mm slices ranging at 14 cardiac phase points. Data sets were obtained from 17 patients on which two such scans were performed 6 to 12 months apart. Automated segmentation, centerline generation, and registration of centerlines between phases was performed, followed by calculation of cross-sectional areas and regional and local pulsatility. Results: Pulsatility calculations for the supraceliac region were very reproducible between earlier and later scans of the same patient, with average differences less than 1% for pulsatility values ranging from 2% to 13%. Local radial pulsatilities were also reproducible to within ~1%. Aneurysm volume changes between scans can also be quantified. Conclusion: Automated segmentation, centerline generation, and registration of temporally resolved CTA datasets permit measurements of regional changes in cross-sectional area over the course of the cardiac cycle (i.e., regional aortic pulsatility). These measurements are reproducible between scans 6-12 months apart, with differences in aortic areas reflecting both aneurysm remodeling and changes in blood pressure. Regional pulsatilities ranged from 2 to 13% but were reproducible at the 1% level.

  18. A new method for Fourier analysis in ECG-gated cardiac blood pool emission computed tomography (ECT)

    SciTech Connect

    Ito, T.; Maeda, H.; Takeda, K.; Nakagawa, T.; Yamaguchi, N.; Konishi, T.; Ichikawa, T.

    1984-01-01

    An integrated technique for Fourier analysis in multigated blood pool ECT study has been developed. Following the administration of 15-20 mCi of Tc-99m RBC, ECG-gated cardiac blood pool data were acquired using an ECT system with dual opposed gamma cameras. Fundamental studies for data acquisition showed that acquisition time of 10 sec. for each projection, 14 divisions of one cardiac cycle and angular interval of 6/sup 0/ (60 projections over 360/sup 0/) were reasonable for clinical purpose. Total acquisition time was about 5 minutes under these conditions. Data were processed as follows: 1) Transaxial (TA) tomographic images in every phase of cardiac cycle were reconstructed by convolution algorithm; 2) TA images were rotated to construct sagittal (SAG) and short axial (S-A) oblique-angle tomography which are respectively parallel and perpendicular to the long axis of either of the ventricles; 3) Images covering the portion other than the purposed ventricle were eliminated from the series of SAG images in every phase of the cycle; 4) Images in the same phase were summed to construct a series of SAG and S-A planar images; and 5) Fourier analysis was made to construct phase and amplitude images. The advantages of this method are that the phase and amplitude images from arbitrary directions can be obtained, that the region of interest can be selected on a three dimensional basis, eliminating the overlapping activity of the other ventricle or neighbouring tissues, that the diseased areas can be easily and accurately localized even in small inferior wall myocardial infarction and that patient study can be finished within 5 minutes.

  19. The effect of head size/shape, miscentering, and bowtie filter on peak patient tissue doses from modern brain perfusion 256-slice CT: How can we minimize the risk for deterministic effects?

    SciTech Connect

    Perisinakis, Kostas; Seimenis, Ioannis; Tzedakis, Antonis; Papadakis, Antonios E.; Damilakis, John

    2013-01-15

    Purpose: To determine patient-specific absorbed peak doses to skin, eye lens, brain parenchyma, and cranial red bone marrow (RBM) of adult individuals subjected to low-dose brain perfusion CT studies on a 256-slice CT scanner, and investigate the effect of patient head size/shape, head position during the examination and bowtie filter used on peak tissue doses. Methods: The peak doses to eye lens, skin, brain, and RBM were measured in 106 individual-specific adult head phantoms subjected to the standard low-dose brain perfusion CT on a 256-slice CT scanner using a novel Monte Carlo simulation software dedicated for patient CT dosimetry. Peak tissue doses were compared to corresponding thresholds for induction of cataract, erythema, cerebrovascular disease, and depression of hematopoiesis, respectively. The effects of patient head size/shape, head position during acquisition and bowtie filter used on resulting peak patient tissue doses were investigated. The effect of eye-lens position in the scanned head region was also investigated. The effect of miscentering and use of narrow bowtie filter on image quality was assessed. Results: The mean peak doses to eye lens, skin, brain, and RBM were found to be 124, 120, 95, and 163 mGy, respectively. The effect of patient head size and shape on peak tissue doses was found to be minimal since maximum differences were less than 7%. Patient head miscentering and bowtie filter selection were found to have a considerable effect on peak tissue doses. The peak eye-lens dose saving achieved by elevating head by 4 cm with respect to isocenter and using a narrow wedge filter was found to approach 50%. When the eye lies outside of the primarily irradiated head region, the dose to eye lens was found to drop to less than 20% of the corresponding dose measured when the eye lens was located in the middle of the x-ray beam. Positioning head phantom off-isocenter by 4 cm and employing a narrow wedge filter results in a moderate reduction of

  20. [Evaluation of Slavic continuity for electrocardiograph (ECG)-gated non-helical scan using multi detector-row computed tomography with 64 data acquisition system].

    PubMed

    Shiotani, Masataka; Ogawa, Masato; Watanabe, Ryo; Shinohara, Tamotsu

    2012-01-01

    Multi detector-row computed tomography with 64 data acquisition systems are widely used for coronary CT angiography with an electrocardiograph (ECG) gated helical scan (HS). Step and shoot with ECG gated non-helical scan (snap shot pulse: SSP) could reduce exposure dose but banding artifact-like discontinuity was observed between adjacent slabs on volume rendering (VR) and curved planner reconstruction (CPR). Therefore, we investigated the factors that influence continuity of VR and CPR images by calculating image properties of Z-axis direction of slab. The observer performance studies were performed for evaluating continuity of simulated blood vessels of VR and CPR images at simulated heart rates: 50, 55, 57 and 60 beat per minute (bpm). As a result, the value of SD at both slab edges in SSP were 20.5% lower than middle part of slab and differences of value of SD were up to 4.4 between adjacent slab edges. Slice thickness of both slab edges were 20.3% thinner than that of the peripheral part of slab. At the border of the adjacent slab, the position of the simulated blood vessel was shifted. VR images of SSP at 57 bpm was indicated as the highest score and HS was significantly superior to SSP at 55 and 60 bpm (p<0.05). In CPR images, there were no significant differences at all simulated heart rates. In conclusion, we considered that VR images of SSP were influenced heart rates except 57 bpm (resonance case) and there was little difference of visibility for discontinuity of both CPR images obtained by SSP and HS.

  1. Assessment of systolic thickening with thallium-201 ECG-gated single-photon emission computed tomography: A parameter for local left ventricular function

    SciTech Connect

    Mochizuki, T.; Murase, K.; Fujiwara, Y.; Tanada, S.; Hamamoto, K.; Tauxe, W.N. )

    1991-08-01

    The authors measured left ventricular (LV) systolic thickening expressed as a systolic thickening ratio in 28 patients, using 201Tl ECG-gated SPECT. Five normals, 15 patients with prior myocardial infarction, 5 with hypertrophic cardiomyopathy, and 3 with dilated cardiomyopathy were studied. The systolic thickening ratio was calculated as ((end-systolic--end-diastolic pixel counts) divided by end-diastolic pixel counts), using the circumferential profile technique of both end-diastolic and end-systolic short axial images. Functional images of the systolic thickening ratio were also displayed with the bull's-eye method. The mean systolic thickening ratio thus calculated were as follows: normals, 0.53 {plus minus} 0.05 (mean {plus minus} 1 s.d.); non-transmural prior myocardial infarction, 0.33 {plus minus} 0.09; transmural prior myocardial infarction, 0.14 {plus minus} 0.05; hypertrophic cardiomyopathy in relatively nonhypertrophied areas, 0.56 {plus minus} 0.11; hypertrophic cardiomyopathy in hypertrophied areas, 0.23 {plus minus} 0.07; and dilated cardiomyopathy, 0.19 {plus minus} 0.02. The systolic thickening ratio analysis by gated thallium SPECT offers a unique approach for assessing LV function.

  2. Assessment of the evaluation of liver T1 mapping imaging applying virtual ECG gating on a modified look-locker inversion recovery (MOLLI) pulse sequence

    NASA Astrophysics Data System (ADS)

    Yu, Seung-Man; Goo, Eun-Hoe; Lee, Suk-Jun; Choe, Bo-Young

    2014-10-01

    A T1 mapping calculation error may occur in a physicochemical environment with large relaxivity. We evaluated through a simulated electrocardiogram (ECG) the administration of a contrast with high relaxivity and its effect on the heart rate by using a modified Look-Locker inversion recovery (MOLLI) pulse sequence. The agarose 2% phantom of high relaxivity environment was developed by diluting gadoxetic acid magnetic resonance imaging (MRI) T1 contrast media. The gold standard T1 determination was based on coronal single section imaging with a 2D inversion-recovery turbo spin echo sequence (2D-IRTSE) in a 3T MR unit. Using the identical 3T MR scanner, we acquired T1 mapping for the MOLLI pulse sequence with various virtual heart rates. T1 mapping data of the two different pulse sequences ( i.e., 2D-IRTSE and MOLLI) were measured to investigate the accuracy and the specificity. An in vivo study was conducted in the same manner as the phantom experiments for liver T1 mapping imaging in three healthy volunteers. The MOLLI pulse sequence showed an error rate of less than 10% at a contrast agent concentration of 0.4 mmol/L, and significant error, compared with the reference value, was observed at 0.6 mmol/L or higher. The percentage error of the T1 value did not correlated with the RR ( i.e., the time between heart beats) change that was observed (P =.270). Based on the in-vivo liver test, T1 mapping imaging of an abdominal organ as the liver can be successfully achieved using the applied virtual ECG gating on the MOLLI sequence.

  3. Evaluation of regional work from ECG-gated SPECT images through solution of equations of continuity for fluids-mechanical cardiac work calculated using thin wall model.

    PubMed

    Maeda, Hisatoshi

    2012-03-01

    Regional contraction work (RCW) of left ventricle (LV) was evaluated from cardiac perfusion images of ECG-gated single photon emission computed tomography (ECG-SPECT). The mechanical work was computed as a product of force and displaced distance. Force was determined from Laplace's law under a rectangle pressure. Deformation of wireframe representing LV was calculated from equations of continuity for two-dimensional fluids. Experiments were performed with homemade life-sized cardiac models. Total contraction work (TCW) and stroke work (SW) were 524.0 ± 166.1 mJ/beat and 709.8 ± 169.5 mJ/beat, respectively, in normal subjects (n = 23). Moderate correlation was seen between TCW and SW (y = -43.4 + 0.779 x, r = 0.815). The regional contraction amplitude (RCA), synchronous contraction index and RCW were 35.4 ± 3.5%, 95.4 ± 3.1% and 5.58 ± 0.97 mJ cm(-2)/beat in normal subjects, whereas those in patients with decreased ejection raction (EF) ≤ 30% (n = 6) were 19.6 ± 7.7%, 64.4 ± 32.2% and 2.58 ± 0.82 mJ cm(-2)/beat (p < 0.0001, Student's t-test). There was a poor correlation between RCW and RCA (y = 1.648 ± 0.116 x, r = 0.501) in normal subjects, suggesting that it might not be suitable to use RCA as an alternative to evaluate RCW.

  4. Cardiac arterial spin labeling using segmented ECG-gated Look-Locker FAIR: variability and repeatability in preclinical studies.

    PubMed

    Campbell-Washburn, Adrienne E; Price, Anthony N; Wells, Jack A; Thomas, David L; Ordidge, Roger J; Lythgoe, Mark F

    2013-01-01

    MRI is important for the assessment of cardiac structure and function in preclinical studies of cardiac disease. Arterial spin labeling techniques can be used to measure perfusion noninvasively. In this study, an electrocardiogram-gated Look-Locker sequence with segmented k-space acquisition has been implemented to acquire single slice arterial spin labeling data sets in 15 min in the mouse heart. A data logger was introduced to improve data quality by: (1) allowing automated rejection of respiration-corrupted images, (2) providing additional prospective gating to improve consistency of acquisition timing, and (3) allowing the recombination of uncorrupted k-space lines from consecutive data sets to reduce respiration corruption. Finally, variability and repeatability of perfusion estimation within-session, between-session, between-animal, and between image rejection criteria were assessed in mice. The criterion used to reject images from the T(1) fit was shown to affect the perfusion estimation. These data showed that the between-animal coefficient of variability (24%) was greater than the between-session variability (17%) and within-session variability (11%). Furthermore, the magnitude of change in perfusion required to detect differences was 30% (within-session) and 55% (between-session) according to Bland-Altman repeatability analysis. These technique developments and repeatability statistics will provide a platform for future preclinical studies applying cardiac arterial spin labeling.

  5. Non-invasive assessment of coronary artery bypass graft with retrospectively ECG-gated four-row multi-detector spiral computed tomography.

    PubMed

    Marano, Riccardo; Storto, Maria Luigia; Maddestra, Nicola; Bonomo, Lorenzo

    2004-08-01

    The purpose of this study was to assess the accuracy of four-row multi-detector CT (MDCT) in the evaluation of coronary artery bypass graft (CABG) in patients with at least a left internal mammary artery (LIMA) grafted to the left anterior descending artery (LAD), because of the conduit of choice in bypass surgery and the greater difficulty of evaluation with non-invasive diagnostic tools. Included in the study were 57 patients with a total of 122 grafts (95 arterial and 27 venous) who underwent MDCT (4x2.5-mm detector-collimation, 3-mm slice width, 1.5-mm reconstruction increment) with retrospective ECG gating. Twelve patients (21%) with high heart rates were given beta-blockers in order to obtain a heart rate lateral>posterior-inferior wall; P=0.002). In the remaining 30 patent grafts (33%), the assessment of stenoses was hampered by surgical clips, calcifications and motion artifacts. Sensitivity and specificity of MDCT for detection of significant graft stenoses were 80 and 96%, respectively. Inter-observer agreement was good ( K=0.73). MDCT seems to be a valuable diagnostic tool for non-invasive assessment of patency of both venous and arterial grafts. An accurate evaluation

  6. Relationship between beat to beat coronary artery motion and image quality in prospectively ECG-gated two heart beat 320-detector row coronary CT angiography.

    PubMed

    Tomizawa, Nobuo; Komatsu, Shuhei; Akahane, Masaaki; Torigoe, Rumiko; Kiryu, Shigeru; Ohtomo, Kuni

    2012-01-01

    The objective was to investigate the influence of the beat-to-beat movement of the coronary arteries on image quality of multi-segment reconstruction (MSR) images. Although MSR improves temporal resolution, image quality would be degraded by beat-to-beat movement of the coronary arteries. In a retrospectively review, 18 patients (mean age, 67.0 years) who underwent coronary CT angiography using a 320-detector row CT were included. The displacement and diameter of coronary artery segments for each of the identified nine landmarks was recorded. The motion ratio was calculated as the division of displacement by diameter. Image quality (IQ) was graded by a four-point scale. The correlation between MSR IQ score and the motion ratio showed stronger negative correlation than that between MSR IQ score and the displacement (r = -0.54 vs. r = -0.36). The average motion ratio for segments in which half-scan reconstruction (HSR) IQ was better than MSR IQ (29.1%, group A) was higher than that for segments in which MSR IQ was better than HSR IQ (16.0%, group C). The motion ratio in group C was lower than 25%. Difference in IQ scores of the HSR images was more frequent in group A than in the remaining segments in which the motion ratio was lower than 25% (16.7% vs. 66.0%; P < 0.0002). The motion ratio could be a better index than the displacement to evaluate the influence of the motion of coronary arteries on image quality. MSR images would be impaired by a motion ratio larger than 25%. Image impairment of one of the HSR images might also impair MSR images.

  7. Erroneous cardiac ECG-gated PET list-mode trigger events can be retrospectively identified and replaced by an offline reprocessing approach: first results in rodents

    NASA Astrophysics Data System (ADS)

    Böning, Guido; Todica, Andrei; Vai, Alessandro; Lehner, Sebastian; Xiong, Guoming; Mille, Erik; Ilhan, Harun; la Fougère, Christian; Bartenstein, Peter; Hacker, Marcus

    2013-11-01

    The assessment of left ventricular function, wall motion and myocardial viability using electrocardiogram (ECG)-gated [18F]-FDG positron emission tomography (PET) is widely accepted in human and in preclinical small animal studies. The nonterminal and noninvasive approach permits repeated in vivo evaluations of the same animal, facilitating the assessment of temporal changes in disease or therapy response. Although well established, gated small animal PET studies can contain erroneous gating information, which may yield to blurred images and false estimation of functional parameters. In this work, we present quantitative and visual quality control (QC) methods to evaluate the accuracy of trigger events in PET list-mode and physiological data. Left ventricular functional analysis is performed to quantify the effect of gating errors on the end-systolic and end-diastolic volumes, and on the ejection fraction (EF). We aim to recover the cardiac functional parameters by the application of the commonly established heart rate filter approach using fixed ranges based on a standardized population. In addition, we propose a fully reprocessing approach which retrospectively replaces the gating information of the PET list-mode file with appropriate list-mode decoding and encoding software. The signal of a simultaneously acquired ECG is processed using standard MATLAB vector functions, which can be individually adapted to reliably detect the R-peaks. Finally, the new trigger events are inserted into the PET list-mode file. A population of 30 mice with various health statuses was analyzed and standard cardiac parameters such as mean heart rate (119 ms ± 11.8 ms) and mean heart rate variability (1.7 ms ± 3.4 ms) derived. These standard parameter ranges were taken into account in the QC methods to select a group of nine optimal gated and a group of eight sub-optimal gated [18F]-FDG PET scans of mice from our archive. From the list-mode files of the optimal gated group, we

  8. Inter-individual variance and cardiac cycle dependency of aortic root dimensions and shape as assessed by ECG-gated multi-slice computed tomography in patients with severe aortic stenosis prior to transcatheter aortic valve implantation: is it crucial for correct sizing?

    PubMed

    Lehmkuhl, Lukas; Foldyna, Borek; Von Aspern, Konstantin; Lücke, Christian; Grothoff, Matthias; Nitzsche, Stefan; Kempfert, Jörg; Haensig, Martin; Rastan, Ardawan; Walther, Thomas; Mohr, Friedrich-Wilhelm; Gutberlet, Matthias

    2013-03-01

    To evaluate the inter-individual variance and the variability of the aortic root dimensions during the cardiac cycle by computed tomography (CT) in patients with severe aortic stenosis prior to transcatheter aortic valve implantation (TAVI). Fifty-six patients (m/w = 16/40, 81 ± 6.8 years), scheduled for a transapical aortic valve implantation with available preprocedural ECG-gated CT were retrospectively included. The evaluation included sizing of the aortic annulus and the aortic sinus, measurements of the coronary topography, aortic valve planimetry and scoring of calcification. The new defined aortic annulus sphericity ratio revealed a mostly elliptical shape with increasing diastolic deformation. The calculated effective diameter (ED), determined from the annulus' lumen area, turned out to be the parameter least affected from cardiac cycle changes while systolic and diastolic annulus dimensions and shape (diameter and area) differed significantly (p < 0.001). In about 70 % of the patients with relevant paravalvular leaks the finally implanted prosthesis was too small according to the CT based calculated ED. The ostial height of the coronaries showed a high variability with a critical minimum range <5 mm. The degree of the aortic calcification did not have an influence on the aortic annulus deformation during the cardiac cycle, but on the occurrence of paravalvular leaks. The aortic root anatomy demonstrated a high inter-individual variability and cardiac cycle dependency. These results must be strongly considered during the patient evaluation prior to TAVI to avoid complications. The systolic effective diameter, as measured by ECG-gated CT, represents an appropriate parameter for sizing the aortic annulus.

  9. ECG gated tomographic reconstruction for 3-D rotational coronary angiography

    PubMed Central

    Hu, Yining; Xie, Lizhe; Nunes, Jean Claude; Bellanger, Jean Jacques; Bedossa, Marc; Toumoulin, Christine

    2010-01-01

    A method is proposed for 3-D reconstruction of coronary from a limited number of projections in rotational angiography. A Bayesian maximum a posteriori (MAP) estimation is applied with a Poisson distributed projection to reconstruct the 3D coronary tree at a given instant of the cardiac cycle. Several regularizers are investigated L0-norm, L1 and L2 -norm in order to take into account the sparsity of the data. Evaluations are reported on simulated data obtained from a 3D dynamic sequence acquired on a 64-slice GE LightSpeed CT scan. A performance study is conducted to evaluate the quality of the reconstruction of the structures. PMID:21096844

  10. Beat-by-beat validation of ECG gating

    SciTech Connect

    Bacharach, S.L.; Green, M.V.; Borer, J.S.; Ostrow, H.G.; Bonow, R.O.; Farkas, S.P.; Johnston, G.S.

    1980-04-01

    Ejection fraction, normalized peak ejection and filling rates, and the time of occurrence of these events relative to the R-wave were determined in each of 512 consecutive individual cardiac cycles in each of 30 patients using an ultra-high-efficiency nonimaging detector system. For a given patient the 512 measurements of each quantity were averaged and compared with the value of this same quantity as determined from an R-wave-gated left-ventricular (LV) time-activity curve (TAC) derived from the same 512 cycles. We conclude (a) that a small but detectable systematic underestimate occurs in some LV function parameters when they are derived from gated LV TACs; (b) that the magnitude of this underestimate is smaller and less variable for systolic than for diastolic measurements; (c) that the magnitude of the underestimate is not greater than 20% in any single patient for diastolic parameters, nor greater than 8% in any individual patient for systolic parameters, and is substantially less for most patients; and (d) that a small subset of patients may require beat-length windowing if the gated values of diastolic parameters are to fall within these limits. Thus LV function measurements obtained from gated TACs adequately reflect the true average of such values during the measurement interval.

  11. [Value of liver perfusion imaging of 256-slice CT 
in evaluation of the cirrhosis].

    PubMed

    Zhan, Yuefu; Wu, Yehua; Chen, Jianqiang; Liu, Fan; Han, Xiangjun

    2016-01-01

    目的:探讨256-CT灌注成像评价代偿期和失代偿期肝硬化的价值。方法:分析2012年12月至2014年6月经肝穿刺活检和影像学、血液学、生物化学检查筛选出的20例肝硬化患者,根据肝穿刺结果和Child-Pugh评分将患者分为肝硬化代偿期组(n=8)和肝硬化失代偿期组(n=12),并选择同期无肝脾疾病者作为对照组(n=11),利用256-CT进行肝灌注(256-CT liver perfusion,256-CTP)。采用256-CTP模式计算灌注参数,包括肝动脉灌注(hepatic arterial perfusion,HAP)、门静脉灌注(portal venous perfusion,PVP)、总肝灌注(total liver perfusion,TLP)、肝动脉灌注指数(hepatic perfusion index,HPI);采用大体灌注模式计算灌注参数,包括肝灌注(liver perfusion,LP)、增强峰值(peak enhanced,PE)、达峰时间(time to peak,TTP)、血容积(blood volume,BV)。采用非参数Spearman检验分析肝硬化分期与各灌注参数值之间的相关性;采用ROC曲线评价各灌注指标预测肝硬化程度的能力,选择约登指数最大作为截断点,计算曲线下面积(area under curve,AUC)、敏感度及特异度。结果:对照组、肝硬化代偿期组、肝硬化失代偿期组PVP分别为(76.63±37.26),(38.78±16.13)和(36.14±15.31) mL/(100 mL·min);TLP分别为(98.48±43.58),(55.63±14.47)和(54.41±
20.81) mL/(100 mL·min);PE分别为(55.62±18.25),(44.11±5.79)和(41.08±7.74) HU,均表现为逐渐下降趋势,各组间差异均有统计学意义(均P<0.05);HPI分别为(19.50±6.08)%,(31.81±16.48)%和(34.47±16.04)%;TTP分别为(37.32±8.59),(47.06±14.61)和(59.86±20.87) s,表现为逐渐上升趋势,各组间差异均有统计学意义(均P<0.05)。HAP,LP和BV各组间比较差异均无统计学意义(均P>0.05)。PVP,TLP,PE和LP与肝硬化分期呈负相关(分别r=−0.592,−0.567,−0.409和−0.569,均P<0.05);HPI,TTP与肝硬化分期呈正相关(分别r=0.434和0.538,均P<0.05)。HPI和TTP对肝硬化具有较高的预测效度,ROC曲线对预测肝硬化及肝硬化失代偿期程度TTP略优于HPI。结论:256-CTP可测量多个灌注参数,为评估肝硬化提供更多信息,能够整体、定量反映肝硬化的血流动力学改变;其中TTP对预测肝硬化及肝硬化失代偿期程度具有较高效能。.

  12. Respiratory-gated segment reconstruction for radiation treatment planning using 256-slice CT-scanner during free breathing

    NASA Astrophysics Data System (ADS)

    Mori, Shinichiro; Endo, Masahiro; Kohno, Ryosuke; Minohara, Shinichi; Kohno, Kazutoshi; Asakura, Hiroshi; Fujiwara, Hideaki; Murase, Kenya

    2005-04-01

    The conventional respiratory-gated CT scan technique includes anatomic motion induced artifacts due to the low temporal resolution. They are a significant source of error in radiotherapy treatment planning for the thorax and upper abdomen. Temporal resolution and image quality are important factors to minimize planning target volume margin due to the respiratory motion. To achieve high temporal resolution and high signal-to-noise ratio, we developed a respiratory gated segment reconstruction algorithm and adapted it to Feldkamp-Davis-Kress algorithm (FDK) with a 256-detector row CT. The 256-detector row CT could scan approximately 100 mm in the cranio-caudal direction with 0.5 mm slice thickness in one rotation. Data acquisition for the RS-FDK relies on the assistance of the respiratory sensing system by a cine scan mode (table remains stationary). We evaluated RS-FDK in phantom study with the 256-detector row CT and compared it with full scan (FS-FDK) and HS-FDK results with regard to volume accuracy and image noise, and finally adapted the RS-FDK to an animal study. The RS-FDK gave a more accurate volume than the others and it had the same signal-to-noise ratio as the FS-FDK. In the animal study, the RS-FDK visualized the clearest edges of the liver and pulmonary vessels of all the algorithms. In conclusion, the RS-FDK algorithm has a capability of high temporal resolution and high signal-to-noise ratio. Therefore it will be useful when combined with new radiotherapy techniques including image guided radiation therapy (IGRT) and 4D radiation therapy.

  13. Assessments of Coronary Artery Visibility and Radiation Dose in Infants with Congenital Heart Disease on Cardiac 128-slice CT and on Cardiac 64-slice CT.

    PubMed

    Cui, Y; Huang, M; Zheng, J; Li, J; Liu, H; Liang, C

    2016-01-01

    The aim of this study was to compare the coronary artery visibility and radiation dose in infants with CHD on cardiac 128-slice CT and on cardiac 64-slice CT. The images of 200 patients were analyzed in this study, 100 patients were selected randomly from a group of 789 infants (<1 years old) with CHD undergoing 128-slice CT prospective ECG-triggered axial scan, and 100 were selected randomly from 911 infants with CHD undergoing 64-slice CT retrospective ECG-gated spiral scan. The visibility of coronary artery segments was graded on a four-point scale. The coronary arteries were considered to be detected or visible when grade was 2 or higher. The visibility of the coronary artery segments and the radiation dose was compared between the two groups. Except for the rate of LM (96 vs. 99%), the detection rates of the total, LAD, LCX, RCA, and the proximal segment of the RCA in the 256-slice CT group were significantly higher than those in the 64-slice CT group (51.7, 53.33, 33.67, 53.33, and 99 vs. 34.8, 34.33, 18, 30.67, and 75%, respectively). The counts of visibility score (4/3/2/1) for the LM and the proximal segment of the RCA were 62/22/12/4 and 56/20/17/7, respectively, in the 128-slice CT group and 17/42/30/1 and 9/30/38/25, respectively, in the 64-slice CT group. There were significant differences, especially for score 4 and 3, between the two groups. The radiation dose in the 128-slice CT group was significantly decreased than those in the 64-slice CT group (CTDIvol 1.88 ± 0.51 vs. 5.61 ± 0.63 mGy; SSDE 4.48 ± 1.15 vs. 13.97 ± 1.52 mGy; effective radiation dose 1.36 ± 0.44 vs. 4.06 ± 0.7 mSv). With reduced radiation dose, the visibility of the coronary artery in infants with CHD via prospective ECG-triggered mode on a 128-slice CT is superior to that of the 64-slice CT using retrospective ECG-gated spiral mode.

  14. Carotid artery and aortic arch imaging with ECG gating in DSA

    SciTech Connect

    Francis, D.A.; Sheldon, J.J.; Soila, K.; Tobias, J.

    1985-06-01

    New computer software for gated digital subtraction angiography imaging was used to study 57 patients over 3 months. Better mask registration on isolated sets of systolic and diastolic images improved image quality. Detail of vessel outline and lesion was better than that seen on nongated images.

  15. Can left ventricular function be assessed on non-ECG-gated CT?

    PubMed

    Minkowitz, Shlomo; Haramati, Linda B; Zalta, Benjamin; Spindola-Franco, Hugo F; Christos, Paul J; Levsky, Jeffrey M

    2014-01-01

    To evaluate whether non-gated computed tomography (CT) can assess left ventricular (LV) function, 101 patients with both CT and echocardiography were selected, with ejection fraction <50% on echocardiography used as a reference standard. CTs were blindly reevaluated, and qualitative assessment of LV dysfunction on CT correlated with echocardiographic dysfunction, odds ratio of 21.0 (95% confidence interval=6.55-71.0), specificity of 86% (56/65). Systolic and diastolic images were identified on CT, and the ratio of systolic to diastolic LV internal diameters and ratio of LV to RV internal diameter were determined, both showing correlation with LV dysfunction on echocardiography (P<.0001). Non-gated CT can be used to predict LV dysfunction. PMID:24794203

  16. Biodiversity Prospecting.

    ERIC Educational Resources Information Center

    Sittenfeld, Ana; Lovejoy, Annie

    1994-01-01

    Examines the use of biodiversity prospecting as a method for tropical countries to value biodiversity and contribute to conservation upkeep costs. Discusses the first agreement between a public interest organization and pharmaceutical company for the extraction of plant and animal materials in Costa Rica. (LZ)

  17. Quantitative analysis of arterial flow properties for detection of non-calcified plaques in ECG-gated coronary CT angiography

    NASA Astrophysics Data System (ADS)

    Wei, Jun; Zhou, Chuan; Chan, Heang-Ping; Chughtai, Aamer; Agarwal, Prachi; Kuriakose, Jean; Hadjiiski, Lubomir; Patel, Smita; Kazerooni, Ella

    2015-03-01

    We are developing a computer-aided detection system to assist radiologists in detection of non-calcified plaques (NCPs) in coronary CT angiograms (cCTA). In this study, we performed quantitative analysis of arterial flow properties in each vessel branch and extracted flow information to differentiate the presence and absence of stenosis in a vessel segment. Under rest conditions, blood flow in a single vessel branch was assumed to follow Poiseuille's law. For a uniform pressure distribution, two quantitative flow features, the normalized arterial compliance per unit length (Cu) and the normalized volumetric flow (Q) along the vessel centerline, were calculated based on the parabolic Poiseuille solution. The flow features were evaluated for a two-class classification task to differentiate NCP candidates obtained by prescreening as true NCPs and false positives (FPs) in cCTA. For evaluation, a data set of 83 cCTA scans was retrospectively collected from 83 patient files with IRB approval. A total of 118 NCPs were identified by experienced cardiothoracic radiologists. The correlation between the two flow features was 0.32. The discriminatory ability of the flow features evaluated as the area under the ROC curve (AUC) was 0.65 for Cu and 0.63 for Q in comparison with AUCs of 0.56-0.69 from our previous luminal features. With stepwise LDA feature selection, volumetric flow (Q) was selected in addition to three other luminal features. With FROC analysis, the test results indicated a reduction of the FP rates to 3.14, 1.98, and 1.32 FPs/scan at sensitivities of 90%, 80%, and 70%, respectively. The study indicated that quantitative blood flow analysis has the potential to provide useful features for the detection of NCPs in cCTA.

  18. In-vivo regional myocardial perfusion measurements in a porcine model by ECG-gated multislice computed tomography

    NASA Astrophysics Data System (ADS)

    Stantz, Keith M.; Liang, Yun; Meyer, Cristopher A.; Teague, Shawn; Stecker, Michael; Hutchins, Gary; McLennan, Gordon; Persohn, Scott

    2003-05-01

    Purpose: To evaluate whether functional multi-slice computed tomography (MSCT) can identify regional areas of normally perfused and ischemic myocardium in a porcine model. Material and Methods: Three out bred pigs, two of which had ameroids surgically implanted to constrict flow within the LAD and LCx coronary arteries, were injected with 25 mL of iopromide (Isovue) at a rate of 5 mL/second via the femoral or jugular vein. Sixty axial scans along the short axis of the heart was acquired on a 16-slice CT scanner (Philips MX8000-IDT) triggered at end-diastole of the cardiac cycle and acquiring an image within 270 msec. A second series of scans were taken after an intravenous injection of a vasodilator, 150 μg/kg/min of adenosine. ROIs were drawn around the myocardial tissue and the resulting time-density curves were used to extract perfusion values. Results: Determination of the myocardial perfusion and fractional blood volume implementing three different perfusion models. A 5-point averaging or 'smoothing' algorithm was employed to effectively filter the data due to its noisy nature. The (preliminary) average perfusion and fractional blood volume values over selected axial slices for the pig without an artificially induced stenosis were measured to be 84 +/- 22 mL/min/100g-tissue and 0.17 +/- 0.04 mL/g-tissue, the former is consistent with PET scan and EBCT results. The pig with a stenosis in the left LAD coronary artery showed a reduced global perfusion value -- 45 mL/min/100g-tissue. Correlations in regional perfusion values relative to the stenosis were weak. During the infusion of adenosine, averaged perfusion values for the three subjects increased by 46 (+/-45) percent, comparable to increases measured with PET. Conclusion: Quantifying global perfusion values using MDCT appear encouraging. Future work will focus resolving the systematic effects from noise due to signal fluctuation from the porcine tachyardia (80-93 BPM) and provide a more robust measurement of regional myocardial perfusion throughout the heart.

  19. Prospective Optimization

    PubMed Central

    Sejnowski, Terrence J.; Poizner, Howard; Lynch, Gary; Gepshtein, Sergei; Greenspan, Ralph J.

    2014-01-01

    Human performance approaches that of an ideal observer and optimal actor in some perceptual and motor tasks. These optimal abilities depend on the capacity of the cerebral cortex to store an immense amount of information and to flexibly make rapid decisions. However, behavior only approaches these limits after a long period of learning while the cerebral cortex interacts with the basal ganglia, an ancient part of the vertebrate brain that is responsible for learning sequences of actions directed toward achieving goals. Progress has been made in understanding the algorithms used by the brain during reinforcement learning, which is an online approximation of dynamic programming. Humans also make plans that depend on past experience by simulating different scenarios, which is called prospective optimization. The same brain structures in the cortex and basal ganglia that are active online during optimal behavior are also active offline during prospective optimization. The emergence of general principles and algorithms for goal-directed behavior has consequences for the development of autonomous devices in engineering applications. PMID:25328167

  20. Prospect redux

    NASA Technical Reports Server (NTRS)

    Jacquemoud, S.; Ustin, S. L.; Verdebout, J.; Schmuck, G.; Andreoli, G.; Hosgood, B.

    1995-01-01

    The remote estimation of leaf biochemical content from spaceborne platforms has been the subject of many studies aimed at better understanding of terrestrial ecosystem functioning. The major ecological processes involved in exchange of matter and energy, like photosynthesis, primary production, evaportranspiration, respiration, and decomposition can be related to plant properties e.g., chlorophyll, water, protein, cellulose and lignin contents. As leaves represent the most important plant surfaces interacting with solar energy, a top priority has been to relate optical properties to biochemical constituents. Two different approaches have been considered: first, statistical correlations between the leaf reflectance (or transmittance) and biochemical content, and second, physically based models of leaf scattering and absorption developed using the laws of optics. Recently reviewed by Verdebout et al., the development of models of leaf optical properties has resulted in better understanding of the interaction of light with plant leaves. Present radiative transfer models mainly use chlorophyll and/or water contents as input parameters to calculate leaf reflectance. Inversion of these models allows to retrieve these constituents from spectrophotometric measurements. Conel et al. recently proposed a two-stream Kubelka-Munk model to analyze the influence of protein, cellulose, lignin, and starch on leaf reflectance, but in fact, the estimation of leaf biochemistry from remote sensing is still an open question. In order to clarify it, a laboratory experiment associating visible/infrared spectra of plan leaves both with physical measurements and biochemical analyses was conducted at the Joint Research Center during the summer of 1993. This unique data set has been used to upgrade the PROSPECT model, by including leaf biochemistry.

  1. Mars Airborne Prospecting Spectrometer

    NASA Astrophysics Data System (ADS)

    Steinkraus, J. M.; Wright, M. W.; Rheingans, B. E.; Steinkraus, D. E.; George, W. P.; Aljabri, A.; Hall, J. L.; Scott, D. C.

    2012-06-01

    One novel approach towards addressing the need for innovative instrumentation and investigation approaches is the integration of a suite of four spectrometer systems to form the Mars Airborne Prospecting Spectrometers (MAPS) for prospecting on Mars.

  2. Psychophysiology of prospective memory.

    PubMed

    Rothen, Nicolas; Meier, Beat

    2014-01-01

    Prospective memory involves the self-initiated retrieval of an intention upon an appropriate retrieval cue. Cue identification can be considered as an orienting reaction and may thus trigger a psychophysiological response. Here we present two experiments in which skin conductance responses (SCRs) elicited by prospective memory cues were compared to SCRs elicited by aversive stimuli to test whether a single prospective memory cue triggers a similar SCR as an aversive stimulus. In Experiment 2 we also assessed whether cue specificity had a differential influence on prospective memory performance and on SCRs. We found that detecting a single prospective memory cue is as likely to elicit a SCR as an aversive stimulus. Missed prospective memory cues also elicited SCRs. On a behavioural level, specific intentions led to better prospective memory performance. However, on a psychophysiological level specificity had no influence. More generally, the results indicate reliable SCRs for prospective memory cues and point to psychophysiological measures as valuable approach, which offers a new way to study one-off prospective memory tasks. Moreover, the findings are consistent with a theory that posits multiple prospective memory retrieval stages.

  3. Prospective ergonomics: origin, goal, and prospects.

    PubMed

    Robert, Jean-Marc; Brangier, Eric

    2012-01-01

    So far ergonomics has been concerned with two categories of activities: correction and design. We propose to add a third category: prospection, and by so doing, we introduce a new series of activities that opens up the future of ergonomics. Corrective ergonomics relates to the past and comes with a demand and a client. It is turned towards the correction of existing situations and aims to reduce or eliminate problems. Here, after delimiting and defining the problem, the challenge is to find the best solution. Ergonomics for design relates to the present and also comes with a demand and a client. It is turned towards the design of new artefacts that have already been identified by a client, and that will allow users to do some activity and attain their goals. Here, after defining the scope of the project and the functional requirements, the challenge is to do the best design. Finally, prospective ergonomics relates to the future and does not come with a demand and a client. It is turned towards the creation of future things that have not been identified yet. Here the challenge is to detect existing user needs or anticipate future ones, and imagine solutions. These three categories of activities overlap and are not exclusive of each other. In this paper we define prospective ergonomics and compare it with corrective ergonomics and ergonomics for design. We describe its origin, goal, and prospects, we analyze its impacts on education and practice, and we emphasize the need of new collaboration between ergonomics and other disciplines.

  4. Prospective cognition in rats

    PubMed Central

    Crystal, Jonathon D.

    2012-01-01

    Efforts to develop animal models of memory are critical for understanding the neural substrate of memory. Memory is essential for daily life and enables information to be stored and retrieved after seconds to years. The ability to remember episodes from the past is thought to be related to the ability to plan for the future. Here we focus on a particular aspect of prospective cognition, namely the ability to remember to take action when a future scenario occurs. This review focuses on a recently developed method to evaluate prospective memory in the rat. Available evidence suggests that rats remember to take action in the future, but little is known about the temporal specificity of such memories or about the flexibility and limitations of prospective memories. Recent studies that suggest that rats remember a specific past episode are reviewed to underscore potential approaches that may be used to explore the range and limits of prospective cognition. The review highlights some directions to explore, including the temporal specificity of prospective cognition, the range of flexibility or creativity within prospective cognition, and the constraints imposed by multiple motivational systems. PMID:23180886

  5. Prospective memory: A comparative perspective

    PubMed Central

    Crystal, Jonathon D.; Wilson, A. George

    2014-01-01

    Prospective memory consists of forming a representation of a future action, temporarily storing that representation in memory, and retrieving it at a future time point. Here we review the recent development of animal models of prospective memory. We review experiments using rats that focus on the development of time-based and event-based prospective memory. Next, we review a number of prospective-memory approaches that have been used with a variety of non-human primates. Finally, we review selected approaches from the human literature on prospective memory to identify targets for development of animal models of prospective memory. PMID:25101562

  6. Prospecting for lunar resources

    NASA Astrophysics Data System (ADS)

    Taylor, G.; Martel, L.

    Large space settlements on the Moon (thousands of people) will require use of indigenous resources to build and maintain the infrastructure and generate products for export. Prospecting for these resources is a crucial step in human migration to space and needs to begin before settlement and the establishment of industrial complexes. We are devising a multi-faceted approach to prospect for resources. A central part of this work is developing the methodology for prospecting the Moon and other planetary bodies. This involves a number of investigations: (1) It is essential to analyze the economics of planetary ore deposits. Ore deposits are planetary materials that we can mine, process, and deliver to customers at a profit. The planetary context tosses in some interesting twists to this definition. (2) We are also making a comprehensive theoretical assessment of potential lunar ore deposits. Our understanding of the compositions, geological histories, and geological processes on the Moon will lead to significant differences in how we assess wh a t types of ores could be present. For example, the bone-dry nature of the Moon (except at the poles) eliminates all ore deposits associated with hydrothermal fluids. (3) We intend to search for resources using existing data for the Moon. Thus, prospecting can begin immediately. We have a wealth of remote sensing data for the Moon. We also have a good sampling of the Moon by the Apollo and Luna missions, and from lunar meteorites. We can target specific types of deposits already identified (e.g. lunar pyroclastic deposits) and look for other geological settings that might have produced ores and other materials of economic value. Another approach we will take is to examine all data available to look for anomalies. Examples are unusual spectral properties, large disagreements between independent techniques that measure the same property, unusual elemental ratios, or simply exceptional properties such as elemental abundances much

  7. Suggestions for prospecting

    USGS Publications Warehouse

    ,

    1989-01-01

    Prospectors have contributed much to the development of this Nation's mineral resources. Since the time of the earliest settlement, the need for iron for tools and guns, lead for bullets, and copper for utensils has prompted a search for sources of these metals. The lure of gold and silver provided the impetus for much of the development in the West between 1850 and 1910. Later, prospectors carried out successful ventures to fulfill the country's expanding industrial demands for other metals such as zinc, molybdenum, tungsten, chromium, vanadium, and many others. Even America's uninhabited rugged mountains or barren deserts have been prospected although perhaps only at a reconnaissance scale.

  8. Applied Astronomy: Asteroid Prospecting

    NASA Astrophysics Data System (ADS)

    Elvis, M.

    2013-09-01

    In the age of asteroid mining the ability to find promising ore-bearing bodies will be valuable. This will give rise to a new discipline- "Applied Astronomy". Just as most geologists work in industry, not in academia, the same will be true of astronomers. Just how rare or common ore-rich asteroids are likely to be, and the skills needed to assay their value, are discussed here, with an emphasis on remote - telescopic - methods. Also considered are the resources needed to conduct extensive surveys of asteroids for prospecting purposes, and the cost and timescale involved. The longer-term need for applied astronomers is also covered.

  9. Methane Clathrate Hydrate Prospecting

    NASA Technical Reports Server (NTRS)

    Duxbury, N.; Romanovsky, V.

    2003-01-01

    A method of prospecting for methane has been devised. The impetus for this method lies in the abundance of CH4 and the growing shortages of other fuels. The method is intended especially to enable identification of subpermafrost locations where significant amounts of methane are trapped in the form of methane gas hydrate (CH4(raised dot)6H2O). It has been estimated by the U.S. Geological Survey that the total CH4 resource in CH4(raised dot) 6H2O exceeds the energy content of all other fossil fuels (oil, coal, and natural gas from non-hydrate sources). Also, CH4(raised dot)6H2O is among the cleanest-burning fuels, and CH4 is the most efficient fuel because the carbon in CH4 is in its most reduced state. The method involves looking for a proxy for methane gas hydrate, by means of the combination of a thermal-analysis submethod and a field submethod that does not involve drilling. The absence of drilling makes this method easier and less expensive, in comparison with prior methods of prospecting for oil and natural gas. The proposed method would include thermoprospecting in combination with one more of the other non-drilling measurement techniques, which could include magneto-telluric sounding and/or a subsurface-electrical-resistivity technique. The method would exploit the fact that the electrical conductivity in the underlying thawed region is greater than that in the overlying permafrost.

  10. New Geoelectrical Prospecting Method

    NASA Astrophysics Data System (ADS)

    Mogilatov, V.

    Some advantages and problems of a new geoelectrical prospecting method, vertical electric current soundings (VECS) are discussed. This method is based on using a new source, circular electric dipole (CED). It is unique source for the electrical prospecting, which excite only TM field. The behavior of an inductive source (loop) and a TE process are well known. Note that because of the more rapidly attenuating TM process (the exponential attenuation in a medium with the insulating base), another conventional source of a type of horizontal grounded line (combined source) behaves mostly as inductive, particulary in the late stage. The most remarkable properties of the field in TM transient process include the absence of the normal (quasi-static) magnetic field at the outer surface of a layered medium, as well as the dependence of the process on the vertical geoelectrical struc- ture (rather than on the overall longitudinal conductivity only, which is typical of the processes excited by inductive means). The source (CED-array) is installed in the following way. One of the transmitter poles is grounded in the central point. The other pole is uniformly grounded around with a radius determined by the depth of investigation desired. The author consider results of the initial field tests in the Tartar republic (oil target).

  11. Prospect Theory and Coercive Bargaining

    ERIC Educational Resources Information Center

    Butler, Christopher K.

    2007-01-01

    Despite many applications of prospect theory's concepts to explain political and strategic phenomena, formal analyses of strategic problems using prospect theory are rare. Using Fearon's model of bargaining, Tversky and Kahneman's value function, and an existing probability weighting function, I construct a model that demonstrates the differences…

  12. Prospective Memory Performance across Adolescence

    ERIC Educational Resources Information Center

    Wang, Lijuan; Kliegel, Matthias; Yang, Zhiliang; Liu, Wei

    2006-01-01

    In the present study, the authors explored age differences in event-based prospective memory (PM) across adolescence. The tasks consisted of an ongoing task (OT; i.e., personality questionnaire items, math problems) and an embedded prospective task that required participants to remember to make a special response whenever they encountered a PM cue…

  13. The Prospects Study and Desegregation.

    ERIC Educational Resources Information Center

    Puma, Michael J.

    1997-01-01

    Argues that greater caution is required when drawing conclusions from statistical results than the Armor study has done, and describes the "Prospects" study (begun in 1989), the largest longitudinal study of educational outcomes conducted in the United States. "Prospects" provides much data useful in evaluating the school desegregation situation…

  14. Prospects at high energies

    SciTech Connect

    Quigg, C.

    1988-11-01

    I discuss some possibilities for neutrino experiments in the fixed-target environment of the SPS, Tevatron, and UNK, with their primary proton beams of 0.4, 0.9, and 3.0 TeV. The emphasis is on unfinished business: issues that have been recognized for some time, but not yet resolved. Then I turn to prospects for proton-proton colliders to explore the 1-TeV scale. I review the motivation for new physics in the neighborhood of 1 TeV and mention some discovery possibilities for high-energy, high-luminosity hadron colliders and the implications they would have for neutrino physics. I raise the possibility of the direct study of neutrino interactions in hadron colliders. I close with a report on the status of the SSC project. 38 refs., 17 figs.

  15. Prospecting with neutrinos

    NASA Astrophysics Data System (ADS)

    Bell, Peter M.

    One of the latest attempts to explore the interface between physics and geophysics is the extravagant scheme of Alvaro De Rújula, Sheldon Glashow, Robert Wilson, and Georges Charpak, to be published in Physics Reports. In what these theoretical and experimental physicists described recently as “our mad project” (Physics Today, August 1983), a high-energy neutrino beam is to be used as a geophysical prospecting tool.The beam would be able to look for oil, natural gas, and high-atomic-number metal ores, and it would be able to profile the vertical density distribution of the earth. De Rújula et al. come to this project from the world of big physics machines, so it is natural to expect that the “Geotron,” the field instrument to supply and focus the neutrino beam, is to be big also.

  16. German energy technology prospects.

    PubMed

    Popp, M

    1982-12-24

    After more than 25 years of development of nuclear power and almost 10 years of research and development in numerous areas of nonnuclear energy, there is now a good basis for judging the future prospects of energy technologies in the Federal Republic of Germany. The development of nuclear power has provided an important and economically advantageous new source of energy. Further efforts are needed to establish the nuclear fuel cycle in all stages and to exploit the potential of advanced reactors. In all other areas of energy technology, including energy conservation, new energy sources, and coal, economics has turned out to be the key problem, even at today's energy prices. Opportunities to overcome these economic problems through additional R & D are limited. There is some potential for special applications, and there are many technologies that could contribute to the energy supply of developing countries. In general, however, progress in energy conservation and the use of renewable energy sources will depend on the degree to which energy policy measures can improve their economic basis. For some technologies, such as solar thermal power stations and coal liquefaction, large-scale economic deployment cannot be foreseen today. Instead of establishing costly demonstration projects, emphasis will be put on improving key components of these technologies with the aim of having the most advanced technology available when the economic parameters are more favorable. PMID:17770150

  17. German energy technology prospects.

    PubMed

    Popp, M

    1982-12-24

    After more than 25 years of development of nuclear power and almost 10 years of research and development in numerous areas of nonnuclear energy, there is now a good basis for judging the future prospects of energy technologies in the Federal Republic of Germany. The development of nuclear power has provided an important and economically advantageous new source of energy. Further efforts are needed to establish the nuclear fuel cycle in all stages and to exploit the potential of advanced reactors. In all other areas of energy technology, including energy conservation, new energy sources, and coal, economics has turned out to be the key problem, even at today's energy prices. Opportunities to overcome these economic problems through additional R & D are limited. There is some potential for special applications, and there are many technologies that could contribute to the energy supply of developing countries. In general, however, progress in energy conservation and the use of renewable energy sources will depend on the degree to which energy policy measures can improve their economic basis. For some technologies, such as solar thermal power stations and coal liquefaction, large-scale economic deployment cannot be foreseen today. Instead of establishing costly demonstration projects, emphasis will be put on improving key components of these technologies with the aim of having the most advanced technology available when the economic parameters are more favorable.

  18. ANAIS: Status and prospects

    NASA Astrophysics Data System (ADS)

    Amaré, J.; Cebrián, S.; Cuesta, C.; García, E.; Ginestra, C.; Martínez, M.; Oliván, M. A.; Ortigoza, Y.; Ortiz de Solórzano, A.; Pobes, C.; Puimedón, J.; Sarsa, M. L.; Villar, J. A.; Villar, P.

    2016-07-01

    ANAIS experiment will look for dark matter annual modulation with large mass of ultra-pure NaI(Tl) scintillators at the Canfranc Underground Laboratory (LSC), aiming to confirm the DAMA/LIBRA positive signal in a model-independent way. Two 12.5 kg each NaI(Tl) crystals provided by Alpha Spectra are currently taking data at the LSC. Present status of ANAIS detectors background and general performance is summarized; in particular, thanks to the high light collection efficiency prospects of lowering the threshold down to 1 keVee are reachable. Crystal radiopurity goals are fulfilled for 232Th and 238U chains and 40K activity, although higher than original goal, could be accepted; however, high 210Pb contamination out-of-equilibrium has been identified. More radiopure detectors are being built by Alpha Spectra. The ongoing high quantum efficiency PMT tests and muon veto characterization are also presented. Finally, the sensitivity of the experiment for the annual modulation in the WIMP signal, assuming the already achieved threshold and background in ANAIS-25 is shown. Further improvement should be achieved by reducing both threshold and background, as expected.

  19. Prospective memory in the rat

    PubMed Central

    Wilson, A. George; Crystal, Jonathon D.

    2011-01-01

    The content of prospective memory is comprised of representations of an action to perform in the future. When people form prospective memories, they temporarily put the memory representation in an inactive state while engaging in other activities, and then activate the representation in the future. Ultimately, successful activation of the memory representation yields an action at an appropriate, but temporally distant, time. A hallmark of prospective memory is that activation of the memory representation has a deleterious effect on current ongoing activity. Recent evidence suggests that scrub jays and non-human primates, but not other species, are capable of future planning. We hypothesized that prospective memory produces a selective deficit in performance at the time when rats access a memory representation but not when the memory representation is inactive. Rats were trained in a temporal bisection task (90 min/day). Immediately after the bisection task, half of the rats received an 8-g meal (meal group) and the other rats received no additional food (no-meal group). Sensitivity to time in the bisection task was reduced as the 90-min interval elapsed for the meal group but not for the no-meal group. This time-based prospective-memory effect was not based on response competition, an attentional limit, anticipatory contrast, or fatigue. Our results suggest that rats form prospective memories, which produces a negative side effect on ongoing activity. PMID:21922257

  20. Bacterial Exopolysaccharides: Functionality and Prospects

    PubMed Central

    Nwodo, Uchechukwu U.; Green, Ezekiel; Okoh, Anthony I.

    2012-01-01

    Diverse structural, functional and valuable polysaccharides are synthesized by bacteria of all taxa and secreted into the external environment. These polysaccharides are referred to as exopolysaccharides and they may either be homopolymeric or heteropolymeric in composition and of diverse high molecular weights (10 to 1000 kDa). The material properties of exopolysaccharides have revolutionized the industrial and medical sectors due to their retinue of functional applications and prospects. These applications have been extensive in areas such as pharmacological, nutraceutical, functional food, cosmeceutical, herbicides and insecticides among others, while prospects includes uses as anticoagulant, antithrombotic, immunomodulation, anticancer and as bioflocculants. Due to the extensive applications of bacterial exopolysaccharides, this overview provides basic information on their physiologic and morphologic functions as well as their applications and prospects in the medical and industrial sectors. PMID:23203046

  1. [Business prospects in eastern Indonesia].

    PubMed

    Hatmadji, S H; Kiting, A S; Anwar, E N

    1993-06-01

    "This paper shows the demographic prospect of population in the Eastern part of Indonesia, especially in four provinces: Bali, East Kalimantan, South Sulawesi and South East Sulawesi." The focus is on the sociodemographic characteristics of consumers in the region, and the implications for commerce. (SUMMARY IN ENG)

  2. Scientific knowledge and modern prospecting

    USGS Publications Warehouse

    Neuerburg, G.J.

    1985-01-01

    Modern prospecting is the systematic search for specified and generally ill-exposed components of the Earth's crust known as ore. This prospecting depends entirely on reliable, or scientific knowledge for guidance and for recognition of the search objects. Improvement in prospecting results from additions and refinements to scientific knowledge. Scientific knowledge is an ordered distillation of observations too numerous and too complex in themselves for easy understanding and for effective management. The ordering of these observations is accomplished by an evolutionary hierarchy of abstractions. These abstractions employ simplified descriptions consisting of characterization by selected properties, sampling to represent much larger parts of a phenomenon, generalized mappings of patterns of geometrical and numerical relations among properties, and explanation (theory) of these patterns as functional relations among the selected properties. Each abstraction is predicated on the mode of abstraction anticipated for the next higher level, so that research is a deductive process in which the highest level, theory, is indispensible for the growth and refinement of scientific knowledge, and therefore of prospecting methodology. ?? 1985 Springer-Verlag.

  3. Job Prospects for Marine Engineers.

    ERIC Educational Resources Information Center

    Basta, Nicholas

    1986-01-01

    Marine engineering is one of the smaller disciplines that have grown during recent decades. Job prospects in this field, salaries, types of employers (particularly Navy shipbuilding and infrastructure work), and marine/ocean engineers involvement with environmental issues are discussed. (JN)

  4. Job Prospects for Civil Engineers.

    ERIC Educational Resources Information Center

    Basta, Nicholas

    1985-01-01

    Government programs and renewed industrial activity have combined with stable enrollments to create bright job prospects for civil engineers. Areas with good opportunities include highway reconstruction and rehabilitation, water-resource management, and new factory construction. The subspecialty of structural engineering has a growing need in…

  5. Job Prospects for Metallurgical Engineering.

    ERIC Educational Resources Information Center

    Basta, Nicholas

    1985-01-01

    Job prospects in mining, metal-extraction, steel, and refining industries are depressed, but technological discoveries are opening up new fields for metallurgical engineers. Enrollment/employment opportunities and salaries in these areas are discussed a well as the roles of foreign competition, plastics applications, and ceramics research and…

  6. Prospects: Student Outcomes. Final Report.

    ERIC Educational Resources Information Center

    Puma, Michael J.; Karweit, Nancy; Price, Cristofer; Ricciuti, Anne; Thompson, William; Vaden-Kiernan, Michael

    This report is one of a series presenting findings from "Prospects: The Congressionally Mandated Study of Educational Growth and Opportunity." This study, conducted in response to the 1988 Hawkins-Stafford Amendments, was a major effort to examine the effects of Chapter 1 on student achievement and other school-related educational outcomes. Data…

  7. Job Prospects for Aerospace Engineers.

    ERIC Educational Resources Information Center

    Basta, Nicholas

    1987-01-01

    Discusses the recent trends in job opportunities for aerospace engineers. Mentions some of the political, technological, and economic factors affecting the overall employment picture. Includes a description of the job prospects created by the general upswing of the large commercial aircraft market. (TW)

  8. UV and Optical Detectors: Status and Prospects

    NASA Technical Reports Server (NTRS)

    Woodgate, Bruce; Oegerle, William (Technical Monitor)

    2002-01-01

    UV and visible detectors - status and prospects. The status and prospects for UV and visible detectors for space astrophysics missions will be described, based on the findings of the NASA working group roadmap report, hopefully updated.

  9. Prospective errors determine motor learning

    PubMed Central

    Takiyama, Ken; Hirashima, Masaya; Nozaki, Daichi

    2015-01-01

    Diverse features of motor learning have been reported by numerous studies, but no single theoretical framework concurrently accounts for these features. Here, we propose a model for motor learning to explain these features in a unified way by extending a motor primitive framework. The model assumes that the recruitment pattern of motor primitives is determined by the predicted movement error of an upcoming movement (prospective error). To validate this idea, we perform a behavioural experiment to examine the model’s novel prediction: after experiencing an environment in which the movement error is more easily predictable, subsequent motor learning should become faster. The experimental results support our prediction, suggesting that the prospective error might be encoded in the motor primitives. Furthermore, we demonstrate that this model has a strong explanatory power to reproduce a wide variety of motor-learning-related phenomena that have been separately explained by different computational models. PMID:25635628

  10. Prospects for nuclear safety research

    SciTech Connect

    Beckjord, E.S.

    1995-04-01

    This document is the text of a paper presented by Eric S. Beckjord (Director, Nuclear Regulatory Research/NRC) at the 22nd Water Reactor Safety Meeting in Bethesda, MD in October 1994. The following topics are briefly reviewed: (1) Reactor vessel research, (2) Probabilistic risk assessment, (3) Direct containment heating, (4) Advanced LWR research, (5) Nuclear energy prospects in the US, and (6) Future nuclear safety research. Subtopics within the last category include economics, waste disposal, and health and safety.

  11. Prospects for de-automatization.

    PubMed

    Kihlstrom, John F

    2011-06-01

    Research by Raz and his associates has repeatedly found that suggestions for hypnotic agnosia, administered to highly hypnotizable subjects, reduce or even eliminate Stroop interference. The present paper sought unsuccessfully to extend these findings to negative priming in the Stroop task. Nevertheless, the reduction of Stroop interference has broad theoretical implications, both for our understanding of automaticity and for the prospect of de-automatizing cognition in meditation and other altered states of consciousness.

  12. Prospective memory across the lifespan: investigating the contribution of retrospective and prospective processes.

    PubMed

    Mattli, Florentina; Schnitzspahn, Katharina M; Studerus-Germann, Aline; Brehmer, Yvonne; Zöllig, Jacqueline

    2014-01-01

    Prospective memory performance follows an inverted U-shaped function across the lifespan. Findings on the relative contribution of purely prospective memory and retrospective memory processes within prospective memory to this trajectory are scarce and inconclusive. We analyzed age-related differences in prospective memory performance across the lifespan in a cross-sectional design including six age groups (N = 99, 7-83 years) and investigated possible mechanisms by experimentally disentangling the relative contributions of retrospective memory and purely prospective memory processes. Results confirmed the inverted U-shaped function of prospective memory performance across the lifespan. A significant interaction between process type and age group was observed indicating differential relative contributions of retrospective memory and purely prospective memory processes on the development of prospective memory performance. Our results showed that mainly the pure prospective memory processes within prospective memory lead to lower prospective memory performance in young children and old adults. Moreover, the relative contributions of the retrospective memory and purely prospective memory processes are not uniform at both ends of the lifespan, i.e., in later adulthood the purely prospective memory processes seem to determine performance to an even greater extent than in childhood. Nevertheless, age effects were also observed in the retrospective component which thus contributed to the prospective memory performance differences between the age groups.

  13. Prospective Memory in Parkinson Disease During a Virtual Week: Effects of Both Prospective and Retrospective Demands

    PubMed Central

    Foster, Erin R.; Rose, Nathan S.; McDaniel, Mark A.; Rendell, Peter G.

    2013-01-01

    Objective This study investigated the effect of Parkinson disease (PD) on event-based prospective memory tasks with varying demand on (1) the amount of strategic attentional monitoring required for intention retrieval (prospective component) and (2) the retrospective memory processes required to remember the contents of the intention or the entire constellation of prospective memory tasks. Method Twenty-four older adults with PD and 28 healthy older adults performed the computerized Virtual Week task, a multi-intention prospective memory paradigm that simulates everyday prospective memory tasks. The Virtual Week included regular (low retrospective memory demand) and irregular (high retrospective memory demand) prospective memory tasks with cues that were focal (low strategic monitoring demand) or less focal (high strategic monitoring demand) to the ongoing activity. Results For the regular prospective memory tasks, PD participants were impaired when the prospective memory cues were less focal. For the irregular prospective memory tasks, PD participants were impaired regardless of prospective memory cue type. PD participants also had impaired retrospective memory for irregular tasks, which was associated with worse prospective memory for these tasks during the Virtual Week. Conclusions When retrospective memory demands are minimized, prospective memory in PD can be supported by cues that reduce the executive control demands of intention retrieval. However, PD-related deficits in self-initiated encoding or planning processes have strong negative effects on the performance of prospective memory tasks with increased retrospective memory demand. PMID:23527645

  14. Prospective memory in thalamic amnesia.

    PubMed

    Carlesimo, G A; Costa, A; Serra, L; Bozzali, M; Fadda, L; Caltagirone, C

    2011-07-01

    The contribution of the thalamus to the functioning of prospective memory (PM) is currently unknown. Here we report an experimental investigation of the performance of two patients with bilateral infarcts in the anterior-mesial regions of the thalami on an event-based PM paradigm. One patient, G.P., had a pervasive declarative memory impairment but no significant executive deficit. The other patient, R.F., had a memory deficit limited to verbal material with associated behavioral abnormalities (inertia and apathy); she performed poorly on tests of executive functions. Although both patients performed poorly on the PM task, a qualitative analysis of performance revealed different mechanisms at the base of their impaired PM. G.P. had reduced declarative memory for target words compared with normal controls; but, unforgotten words were normally able to elicit his recall of the prospective intention. Conversely, R.F.'s declarative memory for target words was as accurate as that of normal controls, but she presented a dramatically reduced ratio between the number of target words she recalled and the number of times she activated the prospective intention on the PM task, suggesting that her deficit consisted of difficulty in activating the intention despite normal declarative memory for the target events. In conclusion, results of the present study demonstrate that thalamic structures have an important role in PM processes. They also document that damage to the anterior-mesial regions of the thalami affects PM abilities by two different mechanisms, respectively based on the relative disruption of declarative memory or executive processes functioning, which, in turn, is related to the specific intrathalamic structures involved by the lesions. Indeed, while G.P.'s pervasive declarative memory deficit was underlain by bilateral involvement of the mammillo-thalamic tract, R.F.'s executive and behavioral abnormalities were likely related to bilateral damage of the midline

  15. Trichomoniasis and Lactoferrin: Future Prospects

    PubMed Central

    Sehgal, Rakesh; Goyal, Kapil; Sehgal, Alka

    2012-01-01

    Trichomonas vaginalis is a parasitic protozoan which infects the urogenital tract and requires iron as an essential nutrient. Iron is known to upregulate various adhesins required for cytoadherance and other factors involved in pathogenesis. At mucosal surfaces, iron is chelated by lactoferrin resulting in low levels of free iron. However, pathogens have evolved mechanisms for an increased uptake of iron. The present review highlights the role of iron in survival of Trichomonas during fluctuating concentrations of iron at mucosal surfaces during the menstrual cycle. Future prospects in terms of new drug and vaccine targets related to iron and its receptors have also been described. PMID:22988421

  16. Atmospheric neutrinos: Status and prospects

    NASA Astrophysics Data System (ADS)

    Choubey, Sandhya

    2016-07-01

    We present an overview of the current status of neutrino oscillation studies at atmospheric neutrino experiments. While the current data gives some tantalising hints regarding the neutrino mass hierarchy, octant of θ23 and δCP, the hints are not statistically significant. We summarise the sensitivity to these sub-dominant three-generation effects from the next-generation proposed atmospheric neutrino experiments. We next present the prospects of new physics searches such as non-standard interactions, sterile neutrinos and CPT violation studies at these experiments.

  17. Nanocarbon Technologies: Prospects and Risks

    NASA Astrophysics Data System (ADS)

    Kozyrev, S.; Yakutseni, P.

    In this paper we review the current state and prospects of carbon nano-technologies as a new emerging point for atomic-molecular manipulation, design and discovery connected with fullerenes, carbon nanotubes and biology. The merging nanoscale interface between carbon and biology structures are shortly discussed in terms of fundamental insights and possible applications encompassing nanobionics as lessons from animate nature, artificial modifications of living systems as well as multicomponent molecular structures for biology, physics, chemistry, engineering, and medicine. Protein-based as well as carbohydrates-, lipids-, or DNA-based molecular assemblies loaded with nanocarbon are addressed in the context of the engineering systems design. Several examples from our collaborative work are used to demonstrate connections between points of nano and bio and to show how such an interdisciplinary approach has led us to new ideas and applications. Nanocarbons have little similarity with the well-known biologically active substances. There is no oxygen, nitrogen, phosphorous-containing or other typical moieties, such as common pharmacophoric anchors or groups. In the same time fullerenes demonstrated a wide spectrum of biological activity. Mechanisms of their biological action are still unknown. For this reason our work was focused on the computer-based molecular modeling of the action of nanocarbon structures on the well-known biological structures: proteins, DNA, carbohydrates, and lipid molecules. Possible biological hazards, fundamental questions and prospects associated with nano-carbon technologies are highlighted.

  18. Prospective Biology Teachers' Understanding of Genetics Concepts.

    ERIC Educational Resources Information Center

    Cakir, Mustafa; Crawford, Barbara

    The purpose of this study is to examine one possible source of misconceptions that are held by students of genetics--the teachers. Is there evidence to suggest that prospective biology teachers might have misconceptions about genetics and related concepts? If prospective biology teachers have misconceptions in genetics, how do these misconceptions…

  19. Prospective Science Teachers' Conceptions about Astronomical Subjects

    ERIC Educational Resources Information Center

    Küçüközer, Hüseyin

    2007-01-01

    The main objective of this study was to identify prospective science teachers' conceptions on basic astronomical phenomena. A questionnaire consisting of nine open-ended questions was administered to 327 prospective science teachers. The questionnaire was constructed after extensive review of the literature and took into consideration the reported…

  20. Perceptions of Prospective Teachers about Tolerance Education

    ERIC Educational Resources Information Center

    Sahin, Cavus

    2011-01-01

    The purpose of this study is to ascertain the perceptions of prospective teachers about tolerance education. This research is a descriptive, qualitative study. A semi-structured and non-directive interview technique is used for collecting data. Research is carried out with 30 prospective teachers who attend Canakkale Onsekiz Mart University…

  1. Prospect Identification Research and Staff Service.

    ERIC Educational Resources Information Center

    Ray, Frank P.

    Prospect Identification, Research and Staff Service is described as a system to identify and provide information in depth on the 20, 50, or 200 individuals or organizations who can make impact on the institution if motivated to help. Usually an institutional prospect research system will limit its efforts, in the interest of cost effectiveness, to…

  2. Nucleon decay experiments: status and prospects

    SciTech Connect

    Ayres, D.S.; Beier, E.W.; D'Ettorre Piazzoli, B.; Ernwein, J.; Gaisser, T.K.; Seidel, S.; Sulak, L.R.

    1986-01-01

    We survey the current status and future prospects of experiments to search for nucleon decay. Results from current experiments are summarized, and the background rejection capabilities of various techniques are described. We discuss the prospects for improved sensitivity in the new experiments that are now coming into operation, and the opportunities for the next generation of detectors. 33 refs., 2 figs., 4 tabs.

  3. Prospective Elemantary Science Teachers' Epistemological Beliefs

    ERIC Educational Resources Information Center

    Macaroglu Akgul, Esra; Oztuna Kaplan, Aysun

    2009-01-01

    This research study examined "prospective elementary science teachers' epistemological beliefs". Forty-nine prospective elementary science teachers participated into research. The research was designed in both quantitative and qualitative manner, within the context of "Special Methods in Science Teaching I" course. Participants' epistemological…

  4. Change, Stability and Context: Prospective Teachers' Perceptions

    ERIC Educational Resources Information Center

    Sahin, Abdurrahman; Cokadar, Hulusi

    2009-01-01

    This study aims to explore and compare first-year and fourth-year prospective teachers' perceptions of good teaching, a good teacher, and a good student. A questionnaire with close- and open-ended questions was administered to 142 first-year and 138 fourth-year prospective teachers enrolled in the Faculty of Education at Pamukkale University.…

  5. Prospective Teachers' Perspectives on Microteaching Lesson Study

    ERIC Educational Resources Information Center

    Fernandez, Maria L.; Robinson, Matthew

    2006-01-01

    Microteaching Lesson Study [MLS] is a cooperative learning experience that we felt could challenge our prospective teachers thinking about teaching and support their connection of theory and practice during an initial course on learning to teach mathematics. We studied seventy-four prospective teachers' perspectives on MLS over four sections of…

  6. 36 CFR 228.60 - Prospecting permits.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... negotiated sale. (b) Limitations. Mineral material may be removed from lands under a prospecting permit only... Section 228.60 Parks, Forests, and Public Property FOREST SERVICE, DEPARTMENT OF AGRICULTURE MINERALS Disposal of Mineral Materials Types and Methods of Disposal § 228.60 Prospecting permits. (a)...

  7. Prospects For Quantum Integrated Circuits

    NASA Astrophysics Data System (ADS)

    Bate, R. T.; Frazier, G. A.; Frensley, W. R.; Lee, J. W.; Reed, M. A.

    1987-08-01

    Recent progress in research on resonant tunneling diodes, and on lateral quantization effects in quantum wells renews hope for the development of active unipolar heterojunction devices which incorporate no depletion layers, and hence can be extremely compact in both vertical and lateral dimensions. If such devices meeting the fundamental requirements for ultrahigh density integrated circuits can be developed, and if revolutionary chip architectures which overcome current interconnection limitations can be devised, then a new generation of integrated circuits approaching the ultimate limits of functional density and functional throughput may eventually ensue. Although many of the most challenging problems in this scenario have not yet been addressed, progress is being made in the areas of fabrication and characterization of resonant tunneling devices, simulation of such devices using quantum transport theory, and simulation of nearest-neighbor connected (two-dimensional cellular automaton) architectures. This paper reviews the progress in these areas at Texas Instruments, and discusses the prospects for the future.

  8. Radiation detectors: needs and prospects

    SciTech Connect

    Armantrout, G.A.

    1981-01-01

    Important applications for x- and ..gamma..-ray spectroscopy are found in prospecting, materials characterization, environmental monitoring, the life sciences, and nuclear physics. The specific requirements vary for each application with varying degrees of emphasis on either spectrometer resolution, detection efficiency, or both. Since no one spectrometer is ideally suited to this wide range of needs, compromises are usually required. Gas and scintillation spectrometers have reached a level of maturity, and recent interest has concentrated on semiconductor spectrometers. Germanium detectors are showing continuing refinement and are the spectrometers of choice for high resolution applications. The new high-Z semiconductors, such as CdTe and HgI/sub 2/, have shown steady improvement but are limited in both resolution and size and will likely be used only in applications which require their unique properties.

  9. Prospective Evaluation of Ventriculostomy Infections

    PubMed Central

    Worley, Emmagene; Astle, Sonia

    2015-01-01

    Introduction: Hospital-acquired infections associated with external drainage of ventricular cerebrospinal fluid (CSF) are a significant source of concern for the patients and the provider team alike. Traditional rates of ventriculostomy infection range from 10-17% in a time-dependent fashion. Changing physician and nursing practices fueled this concern over infections.  Objective: We sought to prospectively identify the risk factors associated with ventriculostomy infections as part of a quality assurance project.  Methods: One hundred consecutive patients were evaluated and data were collected on 91. The primary indications for ventriculostomy were subarachnoid hemorrhage (46%), intracerebral hemorrhage (24%), and trauma (22%). Variables prospectively evaluated included pre-incision antibiotics, sterile technique bundling, setting of placement (operating room versus intensive care unit), experience of operator (attending, resident, or physician assistant), catheter type (antibiotic impregnated or not), use of a post-insertion dressing, and in-dwell time of the catheter.  Results: There was only one infection in 91 patients (1.1%). This infection occurred in a patient without an antibiotic-impregnated catheter that was inserted by a resident physician. Compliance with pre-insertion antibiotics was very high, but most other variables had modest deviations in compliance. Conclusion: Infection rate related to external ventricular drainage is very low. Our data suggest that non-antibiotic impregnated catheters may be associated with infection, but that other variables thought to be critical may be of less value. PMID:26430586

  10. Prospects for European labour demand.

    PubMed

    Lindley, R M

    1988-07-01

    The impact of economic and technological trends upon the level and structure of labor demand is examined, exploring the methods used to model the labor market and making special reference to demography and technology. Evidence on recent and prospective changes in labor demand is reviewed for France, Germany, Italy, the Netherlands, and the UK. The models used to explore future employment scenarios usually fail to incorporate the linkages required to fully analyze the various demographic-economic interactions. Further, this is not generally viewed as a limitation, given the time frame of most employment projections and their preoccupation with changes in the structure of labor demand. Medium-term multisectoral models tend to pay more attention to both demographic and technical change, but the treatment of both aspects is limited. The projections provide a framework for considering how both socioeconomic behavior and policy might change to achieve different outcomes. The greater a model's behavioral content, as expressed in its relationships between different variables, the greater the insight obtainable from simulation exercises. The 1st half of the 1970s was characterized by a reduction in German employment, representing the severest of European reactions to the oil crisis. The 2nd half of the decade recorded rapid growth in Italy and the Netherlands. The 1980s started with marked declines in Germany and the UK. Overall, the net gains of the 1970s were lost in the recession following the 2nd oil crisis. In none of the 5 countries studied does any realistic prospect emerge of achieving full employment before 2000. The most optimistic outcome is that unemployment will decline only slowly, it at all. The growth of both new forms and areas of employment will not compensate sufficiently for the loss of jobs elsewhere and the growth of labor supply. The industrial sector will continue to experience change in favor of the service sector but at a slower rate than during

  11. Antiaging therapy: a prospective hypothesis.

    PubMed

    Shahidi Bonjar, Mohammad Rashid; Shahidi Bonjar, Leyla

    2015-01-01

    This hypothesis proposes a new prospective approach to slow the aging process in older humans. The hypothesis could lead to developing new treatments for age-related illnesses and help humans to live longer. This hypothesis has no previous documentation in scientific media and has no protocol. Scientists have presented evidence that systemic aging is influenced by peculiar molecules in the blood. Researchers at Albert Einstein College of Medicine, New York, and Harvard University in Cambridge discovered elevated titer of aging-related molecules (ARMs) in blood, which trigger cascade of aging process in mice; they also indicated that the process can be reduced or even reversed. By inhibiting the production of ARMs, they could reduce age-related cognitive and physical declines. The present hypothesis offers a new approach to translate these findings into medical treatment: extracorporeal adjustment of ARMs would lead to slower rates of aging. A prospective "antiaging blood filtration column" (AABFC) is a nanotechnological device that would fulfill the central role in this approach. An AABFC would set a near-youth homeostatic titer of ARMs in the blood. In this regard, the AABFC immobilizes ARMs from the blood while blood passes through the column. The AABFC harbors antibodies against ARMs. ARM antibodies would be conjugated irreversibly to ARMs on contact surfaces of the reaction platforms inside the AABFC till near-youth homeostasis is attained. The treatment is performed with the aid of a blood-circulating pump. Similar to a renal dialysis machine, blood would circulate from the body to the AABFC and from there back to the body in a closed circuit until ARMs were sufficiently depleted from the blood. The optimal application criteria, such as human age for implementation, frequency of treatments, dosage, ideal homeostasis, and similar concerns, should be revealed by appropriate investigations. If AABFC technology undergoes practical evaluations and gains approval

  12. Prospects for Tokamak Fusion Reactors

    SciTech Connect

    Sheffield, J.; Galambos, J.

    1995-04-01

    This paper first reviews briefly the status and plans for research in magnetic fusion energy and discusses the prospects for the tokamak magnetic configuration to be the basis for a fusion power plant. Good progress has been made in achieving fusion reactor-level, deuterium-tritium (D-T) plasmas with the production of significant fusion power in the Joint European Torus (up to 2 MW) and the Tokamak Fusion Test Reactor (up to 10 MW) tokamaks. Advances on the technologies of heating, fueling, diagnostics, and materials supported these achievements. The successes have led to the initiation of the design phases of two tokamaks, the International Thermonuclear Experimental Reactor (ITER) and the US Toroidal Physics Experiment (TPX). ITER will demonstrate the controlled ignition and extended bum of D-T plasmas with steady state as an ultimate goal. ITER will further demonstrate technologies essential to a power plant in an integrated system and perform integrated testing of the high heat flux and nuclear components required to use fusion energy for practical purposes. TPX will complement ITER by testing advanced modes of steady-state plasma operation that, coupled with the developments in ITER, will lead to an optimized demonstration power plant.

  13. North American tidal power prospects

    NASA Astrophysics Data System (ADS)

    Wayne, W. W., Jr.

    1981-07-01

    Prospects for North American tidal power electrical generation are reviewed. Studies by the US Army Corps of Engineers of 90 possible generation schemes in Cobscook Bay, ME, indicated that maximum power generation rather than dependable capacity was the most economic method. Construction cost estimates for 15 MW bulb units in a single effect mode from basin to the sea are provided; five projects were considered ranging from 110-160 MW. Additional tidal power installations are examined for: Half-Moon Cove, ME (12 MW, 18 ft tide); Cook Inlet, AK, which is shown to pose severe environmental and engineering problems due to fish migration, earthquake hazards, and 300 ft deep silt deposits; and the Bay of Fundy, Canada. This last has a 17.8 MW plant under construction in a 29 ft maximum tide area. Other tidal projects of the Maritime Provinces are reviewed, and it is noted that previous economic evaluations based on an oil price of $16/barrel are in need of revision.

  14. Dual pathways to prospective remembering

    PubMed Central

    McDaniel, Mark A.; Umanath, Sharda; Einstein, Gilles O.; Waldum, Emily R.

    2015-01-01

    According to the multiprocess framework (McDaniel and Einstein, 2000), the cognitive system can support prospective memory (PM) retrieval through two general pathways. One pathway depends on top–down attentional control processes that maintain activation of the intention and/or monitor the environment for the triggering or target cues that indicate that the intention should be executed. A second pathway depends on (bottom–up) spontaneous retrieval processes, processes that are often triggered by a PM target cue; critically, spontaneous retrieval is assumed not to require monitoring or active maintenance of the intention. Given demand characteristics associated with experimental settings, however, participants are often inclined to monitor, thereby potentially masking discovery of bottom–up spontaneous retrieval processes. In this article, we discuss parameters of laboratory PM paradigms to discourage monitoring and review recent behavioral evidence from such paradigms that implicate spontaneous retrieval in PM. We then re-examine the neuro-imaging evidence from the lens of the multiprocess framework and suggest some critical modifications to existing neuro-cognitive interpretations of the neuro-imaging results. These modifications illuminate possible directions and refinements for further neuro-imaging investigations of PM. PMID:26236213

  15. Dual pathways to prospective remembering.

    PubMed

    McDaniel, Mark A; Umanath, Sharda; Einstein, Gilles O; Waldum, Emily R

    2015-01-01

    According to the multiprocess framework (McDaniel and Einstein, 2000), the cognitive system can support prospective memory (PM) retrieval through two general pathways. One pathway depends on top-down attentional control processes that maintain activation of the intention and/or monitor the environment for the triggering or target cues that indicate that the intention should be executed. A second pathway depends on (bottom-up) spontaneous retrieval processes, processes that are often triggered by a PM target cue; critically, spontaneous retrieval is assumed not to require monitoring or active maintenance of the intention. Given demand characteristics associated with experimental settings, however, participants are often inclined to monitor, thereby potentially masking discovery of bottom-up spontaneous retrieval processes. In this article, we discuss parameters of laboratory PM paradigms to discourage monitoring and review recent behavioral evidence from such paradigms that implicate spontaneous retrieval in PM. We then re-examine the neuro-imaging evidence from the lens of the multiprocess framework and suggest some critical modifications to existing neuro-cognitive interpretations of the neuro-imaging results. These modifications illuminate possible directions and refinements for further neuro-imaging investigations of PM.

  16. Nuclear radiation cleanup and uranium prospecting

    DOEpatents

    Mariella, Jr., Raymond P.; Dardenne, Yves M.

    2016-02-02

    Apparatus, systems, and methods for nuclear radiation cleanup and uranium prospecting include the steps of identifying an area; collecting samples; sample preparation; identification, assay, and analysis; and relating the samples to the area.

  17. Effects of sleep deprivation on prospective memory.

    PubMed

    Grundgeiger, Tobias; Bayen, Ute J; Horn, Sebastian S

    2014-01-01

    Sleep deprivation reduces cognitive performance; however, its effects on prospective memory (remembering to perform intended actions) are unknown. One view suggests that effects of sleep deprivation are limited to tasks associated with prefrontal functioning. An alternative view suggests a global, unspecific effect on human cognition, which should affect a variety of cognitive tasks. We investigated the impact of sleep deprivation (25 hours of sleep deprivation vs. no sleep deprivation) on prospective-memory performance in more resource-demanding and less resource-demanding prospective-memory tasks. Performance was lower after sleep deprivation and with a more resource-demanding prospective-memory task, but these factors did not interact. These results support the view that sleep deprivation affects cognition more globally and demonstrate that sleep deprivation increases failures to carry out intended actions, which may have severe consequences in safety-critical situations.

  18. Vision Trouble Can Dim Life's Prospects

    MedlinePlus

    ... page: https://medlineplus.gov/news/fullstory_160136.html Vision Trouble Can Dim Life's Prospects But it's not ... THURSDAY, July 28, 2016 (HealthDay News) -- People with vision problems may face a higher risk of unemployment, ...

  19. Hypnosis Attenuates Executive Cost of Prospective Memory.

    PubMed

    Demeter, Gyula; Szendi, István; Juhász, Marianna; Kovács, Zoltán Ambrus; Boncz, István; Keresztes, Attila; Pajkossy, Péter; Racsmány, Mihály

    2016-01-01

    Prospective memory is the ability to formulate and carry out actions at the appropriate time or in the appropriate context. This study aimed to identify the effect of hypnosis on prospective memory performance and to analyze the involvement of executive control processes in intention realization in a hypnotically altered state of consciousness. In 1 experiment, manipulating hypnotic instruction in a within-subject fashion, the authors explored the event-based prospective memory performance of 23 volunteers in 3 conditions: baseline, expectation, and execution. The primary result was that executing prospective memory responses, at the same accuracy rate, produced a significantly lower cost of ongoing responses in terms of response latency in the hypnotic state than in wake condition. PMID:26894423

  20. Prospect Theory for Online Financial Trading

    NASA Astrophysics Data System (ADS)

    Liu, Yang-Yu; Nacher, Jose C.; Ochiai, Tomoshiro; Martino, Mauro; Altshuler, Yaniv

    2014-03-01

    Prospect theory is widely viewed as the best available descriptive model of how people evaluate risk in experimental settings. According to prospect theory, people make decisions based on the potential value of losses and gains rather than the final outcome. People are risk-averse with respect to gains and risk-seeking with respect to losses, a phenomenon called ``loss aversion''. Despite of the fact that prospect theory has been well studied in behavioral economics at the theoretical level, there exist very few empirical research and most of them has been undertaken with micro-panel data. Here we analyze the trading activities of over 1.5 million members of an online financial trading community over 28 months, aiming to explore the large-scale empirical aspect of prospect theory. By analyzing and comparing the behaviour of ``winners'' and ``losers'', i.e., traders with positive or negative final net profit, we find clear evidence of the loss aversion phenomenon, an essence in prospect theory. This work demonstrates an unprecedented large-scale empirical evidence of prospect theory. It has immediate implication in financial trading, e.g., developing new trading strategies by minimizing the effect of loss aversion. It also provides opportunity to augment online social trading, where users are allowed to watch and follow the trading activity of others, by predicting potential winners based on their historical trading behaviour.

  1. Prospecting for marine gas hydrate resources

    USGS Publications Warehouse

    Boswell, Ray; Shipp, Craig; Reichel, Thomas; Shelander, Dianna; Saeki, Tetsuo; Frye, Matthew; Shedd, William; Collett, Timothy S.; McConnell, Daniel R.

    2016-01-01

    As gas hydrate energy assessment matures worldwide, emphasis has evolved away from confirmation of the mere presence of gas hydrate to the more complex issue of prospecting for those specific accumulations that are viable resource targets. Gas hydrate exploration now integrates the unique pressure and temperature preconditions for gas hydrate occurrence with those concepts and practices that are the basis for conventional oil and gas exploration. We have aimed to assimilate the lessons learned to date in global gas hydrate exploration to outline a generalized prospecting approach as follows: (1) use existing well and geophysical data to delineate the gas hydrate stability zone (GHSZ), (2) identify and evaluate potential direct indications of hydrate occurrence through evaluation of interval of elevated acoustic velocity and/or seismic events of prospective amplitude and polarity, (3) mitigate geologic risk via regional seismic and stratigraphic facies analysis as well as seismic mapping of amplitude distribution along prospective horizons, and (4) mitigate further prospect risk through assessment of the evidence of gas presence and migration into the GHSZ. Although a wide range of occurrence types might ultimately become viable energy supply options, this approach, which has been tested in only a small number of locations worldwide, has directed prospect evaluation toward those sand-hosted, high-saturation occurrences that were presently considered to have the greatest future commercial potential.

  2. 43 CFR 3505.10 - What is a prospecting permit?

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 43 Public Lands: Interior 2 2012-10-01 2012-10-01 false What is a prospecting permit? 3505.10 Section 3505.10 Public Lands: Interior Regulations Relating to Public Lands (Continued) BUREAU OF LAND... AND OIL SHALE Prospecting Permits § 3505.10 What is a prospecting permit? (a) A prospecting...

  3. 43 CFR 3505.10 - What is a prospecting permit?

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 43 Public Lands: Interior 2 2013-10-01 2013-10-01 false What is a prospecting permit? 3505.10 Section 3505.10 Public Lands: Interior Regulations Relating to Public Lands (Continued) BUREAU OF LAND... AND OIL SHALE Prospecting Permits § 3505.10 What is a prospecting permit? (a) A prospecting...

  4. Prospective Optimization with Limited Resources.

    PubMed

    Snider, Joseph; Lee, Dongpyo; Poizner, Howard; Gepshtein, Sergei

    2015-09-01

    The future is uncertain because some forthcoming events are unpredictable and also because our ability to foresee the myriad consequences of our own actions is limited. Here we studied how humans select actions under such extrinsic and intrinsic uncertainty, in view of an exponentially expanding number of prospects on a branching multivalued visual stimulus. A triangular grid of disks of different sizes scrolled down a touchscreen at a variable speed. The larger disks represented larger rewards. The task was to maximize the cumulative reward by touching one disk at a time in a rapid sequence, forming an upward path across the grid, while every step along the path constrained the part of the grid accessible in the future. This task captured some of the complexity of natural behavior in the risky and dynamic world, where ongoing decisions alter the landscape of future rewards. By comparing human behavior with behavior of ideal actors, we identified the strategies used by humans in terms of how far into the future they looked (their "depth of computation") and how often they attempted to incorporate new information about the future rewards (their "recalculation period"). We found that, for a given task difficulty, humans traded off their depth of computation for the recalculation period. The form of this tradeoff was consistent with a complete, brute-force exploration of all possible paths up to a resource-limited finite depth. A step-by-step analysis of the human behavior revealed that participants took into account very fine distinctions between the future rewards and that they abstained from some simple heuristics in assessment of the alternative paths, such as seeking only the largest disks or avoiding the smaller disks. The participants preferred to reduce their depth of computation or increase the recalculation period rather than sacrifice the precision of computation.

  5. A prospective treatment for sepsis.

    PubMed

    Shahidi Bonjar, Mohammad Rashid; Shahidi Bonjar, Leyla

    2015-01-01

    The present paper proposes a prospective auxiliary treatment for sepsis. There exists no record in the published media on the subject. As an auxiliary therapy, efficacious extracorporeal removal of sepsis-causing bacterial antigens and their toxins (BATs) from the blood of septic patients is discussed. The principal component to this approach is a bacterial polyvalent antibody-column (BPVAC), which selectively traps wide spectrum of BATs from blood in an extracorporeal circuit, and detoxified blood returns back to the patient's body. BPVAC treatment would be a device of targeted medicine. Detoxification is performed under supervision of trained personnel using simple blood-circulating machines in which blood circulates from the patient to BPVAC and back to the patient aseptically. BPVACs' reactive sites consist of carbon nanotubes on which a vast spectra of polyvalent BATs-antibodies are bond to. The devise acts as a biological filter that selectively immobilizes harmful BATs from intoxicated blood; however, no dialysis is involved. For effective neutralization, BPVAC provides large contact surface area with blood. BPVAC approach would have advantages of: 1) urgent neutralization of notorious BATs from blood of septic patients; 2) applicability in parallel with conventional treatments; 3) potential to minimize side effects of the malady; 4) applicability for a vast range of BATs; 5) potential to eliminate contact of BATs with internal tissues and organs; 6) tolerability by patients sensitive to antiserum injections; 7) capability for universal application; 8) affectivity when antibiotic-resistant bacteria are involved and the physician has no or limited access to appropriate antibiotics; and 10) being a single-use, disposable, and stand-alone device. Before using it for clinical trials in human beings, it should pass animal evaluations accurately; however, research works should optimize its implementation in human beings. For optimization, it needs appropriate

  6. Prospective Optimization with Limited Resources

    PubMed Central

    Snider, Joseph; Lee, Dongpyo; Poizner, Howard; Gepshtein, Sergei

    2015-01-01

    The future is uncertain because some forthcoming events are unpredictable and also because our ability to foresee the myriad consequences of our own actions is limited. Here we studied how humans select actions under such extrinsic and intrinsic uncertainty, in view of an exponentially expanding number of prospects on a branching multivalued visual stimulus. A triangular grid of disks of different sizes scrolled down a touchscreen at a variable speed. The larger disks represented larger rewards. The task was to maximize the cumulative reward by touching one disk at a time in a rapid sequence, forming an upward path across the grid, while every step along the path constrained the part of the grid accessible in the future. This task captured some of the complexity of natural behavior in the risky and dynamic world, where ongoing decisions alter the landscape of future rewards. By comparing human behavior with behavior of ideal actors, we identified the strategies used by humans in terms of how far into the future they looked (their “depth of computation”) and how often they attempted to incorporate new information about the future rewards (their “recalculation period”). We found that, for a given task difficulty, humans traded off their depth of computation for the recalculation period. The form of this tradeoff was consistent with a complete, brute-force exploration of all possible paths up to a resource-limited finite depth. A step-by-step analysis of the human behavior revealed that participants took into account very fine distinctions between the future rewards and that they abstained from some simple heuristics in assessment of the alternative paths, such as seeking only the largest disks or avoiding the smaller disks. The participants preferred to reduce their depth of computation or increase the recalculation period rather than sacrifice the precision of computation. PMID:26367309

  7. Prospective Coding by Spiking Neurons.

    PubMed

    Brea, Johanni; Gaál, Alexisz Tamás; Urbanczik, Robert; Senn, Walter

    2016-06-01

    Animals learn to make predictions, such as associating the sound of a bell with upcoming feeding or predicting a movement that a motor command is eliciting. How predictions are realized on the neuronal level and what plasticity rule underlies their learning is not well understood. Here we propose a biologically plausible synaptic plasticity rule to learn predictions on a single neuron level on a timescale of seconds. The learning rule allows a spiking two-compartment neuron to match its current firing rate to its own expected future discounted firing rate. For instance, if an originally neutral event is repeatedly followed by an event that elevates the firing rate of a neuron, the originally neutral event will eventually also elevate the neuron's firing rate. The plasticity rule is a form of spike timing dependent plasticity in which a presynaptic spike followed by a postsynaptic spike leads to potentiation. Even if the plasticity window has a width of 20 milliseconds, associations on the time scale of seconds can be learned. We illustrate prospective coding with three examples: learning to predict a time varying input, learning to predict the next stimulus in a delayed paired-associate task and learning with a recurrent network to reproduce a temporally compressed version of a sequence. We discuss the potential role of the learning mechanism in classical trace conditioning. In the special case that the signal to be predicted encodes reward, the neuron learns to predict the discounted future reward and learning is closely related to the temporal difference learning algorithm TD(λ). PMID:27341100

  8. Prospective Optimization with Limited Resources.

    PubMed

    Snider, Joseph; Lee, Dongpyo; Poizner, Howard; Gepshtein, Sergei

    2015-09-01

    The future is uncertain because some forthcoming events are unpredictable and also because our ability to foresee the myriad consequences of our own actions is limited. Here we studied how humans select actions under such extrinsic and intrinsic uncertainty, in view of an exponentially expanding number of prospects on a branching multivalued visual stimulus. A triangular grid of disks of different sizes scrolled down a touchscreen at a variable speed. The larger disks represented larger rewards. The task was to maximize the cumulative reward by touching one disk at a time in a rapid sequence, forming an upward path across the grid, while every step along the path constrained the part of the grid accessible in the future. This task captured some of the complexity of natural behavior in the risky and dynamic world, where ongoing decisions alter the landscape of future rewards. By comparing human behavior with behavior of ideal actors, we identified the strategies used by humans in terms of how far into the future they looked (their "depth of computation") and how often they attempted to incorporate new information about the future rewards (their "recalculation period"). We found that, for a given task difficulty, humans traded off their depth of computation for the recalculation period. The form of this tradeoff was consistent with a complete, brute-force exploration of all possible paths up to a resource-limited finite depth. A step-by-step analysis of the human behavior revealed that participants took into account very fine distinctions between the future rewards and that they abstained from some simple heuristics in assessment of the alternative paths, such as seeking only the largest disks or avoiding the smaller disks. The participants preferred to reduce their depth of computation or increase the recalculation period rather than sacrifice the precision of computation. PMID:26367309

  9. A prospective treatment for sepsis

    PubMed Central

    Shahidi Bonjar, Mohammad Rashid; Shahidi Bonjar, Leyla

    2015-01-01

    The present paper proposes a prospective auxiliary treatment for sepsis. There exists no record in the published media on the subject. As an auxiliary therapy, efficacious extracorporeal removal of sepsis-causing bacterial antigens and their toxins (BATs) from the blood of septic patients is discussed. The principal component to this approach is a bacterial polyvalent antibody-column (BPVAC), which selectively traps wide spectrum of BATs from blood in an extracorporeal circuit, and detoxified blood returns back to the patient’s body. BPVAC treatment would be a device of targeted medicine. Detoxification is performed under supervision of trained personnel using simple blood-circulating machines in which blood circulates from the patient to BPVAC and back to the patient aseptically. BPVACs’ reactive sites consist of carbon nanotubes on which a vast spectra of polyvalent BATs-antibodies are bond to. The devise acts as a biological filter that selectively immobilizes harmful BATs from intoxicated blood; however, no dialysis is involved. For effective neutralization, BPVAC provides large contact surface area with blood. BPVAC approach would have advantages of: 1) urgent neutralization of notorious BATs from blood of septic patients; 2) applicability in parallel with conventional treatments; 3) potential to minimize side effects of the malady; 4) applicability for a vast range of BATs; 5) potential to eliminate contact of BATs with internal tissues and organs; 6) tolerability by patients sensitive to antiserum injections; 7) capability for universal application; 8) affectivity when antibiotic-resistant bacteria are involved and the physician has no or limited access to appropriate antibiotics; and 10) being a single-use, disposable, and stand-alone device. Before using it for clinical trials in human beings, it should pass animal evaluations accurately; however, research works should optimize its implementation in human beings. For optimization, it needs appropriate

  10. Prospective Coding by Spiking Neurons

    PubMed Central

    Brea, Johanni; Gaál, Alexisz Tamás; Senn, Walter

    2016-01-01

    Animals learn to make predictions, such as associating the sound of a bell with upcoming feeding or predicting a movement that a motor command is eliciting. How predictions are realized on the neuronal level and what plasticity rule underlies their learning is not well understood. Here we propose a biologically plausible synaptic plasticity rule to learn predictions on a single neuron level on a timescale of seconds. The learning rule allows a spiking two-compartment neuron to match its current firing rate to its own expected future discounted firing rate. For instance, if an originally neutral event is repeatedly followed by an event that elevates the firing rate of a neuron, the originally neutral event will eventually also elevate the neuron’s firing rate. The plasticity rule is a form of spike timing dependent plasticity in which a presynaptic spike followed by a postsynaptic spike leads to potentiation. Even if the plasticity window has a width of 20 milliseconds, associations on the time scale of seconds can be learned. We illustrate prospective coding with three examples: learning to predict a time varying input, learning to predict the next stimulus in a delayed paired-associate task and learning with a recurrent network to reproduce a temporally compressed version of a sequence. We discuss the potential role of the learning mechanism in classical trace conditioning. In the special case that the signal to be predicted encodes reward, the neuron learns to predict the discounted future reward and learning is closely related to the temporal difference learning algorithm TD(λ). PMID:27341100

  11. [Prospective evaluation of antidepressant discontinuation].

    PubMed

    Mourad, I; Lejoyeux, M; Adès, J

    1998-01-01

    The authors prospectively assessed symptoms induced by the interruption of antidepressants in 16 patients (11 women and 5 men), aged from 33 to 85 years (mean = 52.4 +/- 16.4), treated with antidepressants since at least two weeks. All patients were free of alcohol abuse or dependence disorder and of other dependence to psychoactive substances. None of them presented medical illness. Diagnosis were made by separate evaluations by two authors and confirmed with a semistructered assessment instrument: the Schedule for Affective Disorders and Schizophrenia (Lifetime Version). All patients were submitted to a brutal discontinuation of their antidepressant agent. Patients were assessed twice, before the interruption of the antidepressant, and 72 hours later. Effects of antidepressant interruption were assessed by several means. Modification of anxiety and depression were evaluated using the Montgomery Asberg Depression Rating Scale (MADRS) and the Hamilton Anxiety Scale. Symptoms of withdrawal were assessed with Cassano and al.'s scale SESSH including an evaluation of anxiety, agitation, irritability, anergy, difficulty on concentrating, depersonalization, sleep and appetite disorders, muscle pains, nausea, tremor, sweating, altered taste, hyperosmia, paresthesias, photophobia, motor incoordination, dizziness, hyperacousia pain, delirium. Fourteen of the 16 patients (87.5%) presented modifications of their somatic or psychic state 3 days after the interruption of the antidepressant treatment. Most frequent symptoms were: increase in anxiety (31%), increase in irritability (25%), sleep disorders (19%), decrease of anergia and fatigue (19%). Mean scores of anxiety and depression were not significantly modified by the withdrawal. Following TCAs interruption (7 patients) most frequent symptoms were sleep disorders; increase in anxiety, nausea. Among patients withdrawn from SSRIs (6 patients), most frequent symptoms were increase in anxiety, increase in irritability

  12. [Hemodialysis prospective multicentric quality study].

    PubMed

    Parra, E; Ramos, R; Betriú, A; Paniagua, J; Belart, M; Martín, F; Martínez, T

    2006-01-01

    In medicine a considerable amount of resources are used in research, but very little attention is paid to ensuring that the findings of research are implemented in routine clinical practice. This prospective study has the aim to evaluate the efficiency of some clinical management strategies (feedback, benchmarking and improving plans) on haemodialysis treatment results in 4 different dialysis centres. We collected consensus data related to haemodialysis results every 6-8 months and informed each centre about its own results (feedback) and how these related to the others(benchmarking). We designed improving plans for any bad result detected. By the end of two years of follow up, 294 patients had been included in the study. The results obtained at the end of the study had improved in comparison with those obtained at the beginning (statistically significant) for the following indicators: % of patients with Hb< 11 g/dl, % patients with Kt/v < 1.2, mean Kt/v, mean albumin, % patients with albumin< 3.5 g/dl y % patients with C reactive protein (CRP) > 5 mg/dl. No statistical changes were found in: mean erythropoietin (EPO) doses, blood pressure (BP), phosphorus plasmatic,calcium-phosphorus product, parathormone (PTHi) and vascular access distribution. We explained the absence of any improvement because of adequate start indicators in some areas (BP and vascular access), therapy with limited efficiency (calcitriol, calcium carbonate and others), lack of support resources (dietetic unit) or inadequate design/implementation of improving plans.In conclusion, our intervention illustrates that combined clinical management strategies(feedback, benchmarking and improving plans) are efficiency in improving some areas of haemodialysis treatment (anaemia, dialysis dose, nutrition and inflammation), although it does not improve calcium phosphate metabolism related indicators.

  13. Prospective very young asteroid pairs

    NASA Astrophysics Data System (ADS)

    Galád, A.; Vokrouhlický, D.; Zizka, J.

    2014-07-01

    Several tens of asteroid pairs can be discerned from the background main-belt asteroids. The majority of them are thought to have formed within only the last few 10^6 yr. The youngest recognized pairs have formed more than ≈ 10 kyr ago. As some details of pair formation are still not understood well, the study of young pairs is of great importance. It is mainly because the conditions at the time of the pair formation could be deduced much more reliably for young pairs. For example, space weathering on the surfaces of the components, or changes in their rotational properties (in spin rates, tumbling, coordinates of rotational pole) could be negligible since the formation of young pairs. Also, possible strong perturbations by main-belt bodies on pair formation can be reliably studied only for extremely young pairs. Some pairs can quickly blend in with the background asteroids, so even the frequency of asteroid pair formation could be determined more reliably based on young pairs (though only after a statistically significant sample is at disposal). In our regular search for young pairs in the growing asteroid database, only multiopposition asteroids with very similar orbital and proper elements are investigated. Every pair component is represented by a number of clones within orbital uncertainties and drifting in semimajor axis due to the Yarkovsky effect. We found that, if the previously unrecognized pairs (87887) 2000 SS_{286} - 2002 AT_{49} and (355258) 2007 LY_{4} - 2013AF_{40} formed at the recent very close approach of their components, they could become the youngest known pairs. In both cases, the relative encounter velocities of the components were only ˜ 0.1 m s^{-1}. However, the minimum distances between some clones are too large and a few clones of the latter pair did not encounter recently (within ≈ 10 kyr). The age of some prospective young pairs cannot be determined reliably without improved orbital properties (e.g., the second component of a pair

  14. Prospect theory in the valuation of health.

    PubMed

    Moffett, Maurice L; Suarez-Almazor, Maria E

    2005-08-01

    Prospect theory is the prominent nonexpected utility theory in the estimation of health state preference scores for quality-adjusted life year calculation. Until recently, the theory was not considered to be developed to the point of implementation in economic analysis. This review focuses on the research and evidence that tests the implementation of prospect theory into health state valuation. The typical application of expected utility theory assumes that a decision maker has stable preferences under conditions of risk and uncertainty. Under prospect theory, preferences are dependent on whether the decision maker regards the outcome of a choice as a gain or loss, relative to a reference point. The conceptual preference for standard gamble utilities in the valuation of health states has led to the development of elicitation techniques. Empirical evidence using these techniques indicates that when individual preferences are elicited, a prospect theory consistent framework appears to be necessary for adequate representation of individual health utilities. The relevance of prospect theory to policy making and resource allocation remains to be established. Societal preferences may not need the same attitudes towards risks as individual preferences, and may remain largely risk neutral. PMID:19807267

  15. Prospecting for gold in the United States

    USGS Publications Warehouse

    ,

    1967-01-01

    Prospecting for gold is something that probably everyone dreams of trying at least once. To the person who is mainly concerned with this activity as a vacation diversion, prospecting offers a special excitement. There is a constant hope that the next pan of sediment may be "pay dirt," and no other thrill can compare with that experienced when one sees even a few tiny flecks of gold glittering in the black sand at the bottom of his pan. The search itself is its own reward for the efforts expended by the vacation prospector. The would-be prospector hoping for financial gain, however, should carefully consider all the facts of the situation before deciding to set out on a prospecting expedition.

  16. Prospective Memory in Children and Chimpanzees

    PubMed Central

    Perdue, Bonnie M.; Evans, Theodore A.; Williamson, Rebecca A.; Gonsiorowski, Anna; Beran, Michael J.

    2013-01-01

    Prospective memory involves remembering to do something at a specific time in the future. Here we investigate the beginnings of this ability in young children (3-year-olds; Homo sapiens) and chimpanzees (Pan troglodytes) using an analogous task. Subjects were given a choice between two toys (children) or two food items (chimpanzees). The selected item was delivered immediately, whereas the unselected item was hidden in an opaque container. After completing an ongoing quantity discrimination task, subjects could request the hidden item by asking for it (children) or by pointing to the container and identifying the item on a symbol board (chimpanzees). Children and chimpanzees showed evidence of prospective-like memory in this task, as evidenced by successful retrieval of the item at the end of the task, sometimes spontaneously with no prompting from the experimenter. These findings contribute to our understanding of prospective memory from an ontogenetic and comparative perspective. PMID:23884791

  17. Prospect theory for online financial trading.

    PubMed

    Liu, Yang-Yu; Nacher, Jose C; Ochiai, Tomoshiro; Martino, Mauro; Altshuler, Yaniv

    2014-01-01

    Prospect theory is widely viewed as the best available descriptive model of how people evaluate risk in experimental settings. According to prospect theory, people are typically risk-averse with respect to gains and risk-seeking with respect to losses, known as the "reflection effect". People are much more sensitive to losses than to gains of the same magnitude, a phenomenon called "loss aversion". Despite of the fact that prospect theory has been well developed in behavioral economics at the theoretical level, there exist very few large-scale empirical studies and most of the previous studies have been undertaken with micro-panel data. Here we analyze over 28.5 million trades made by 81.3 thousand traders of an online financial trading community over 28 months, aiming to explore the large-scale empirical aspect of prospect theory. By analyzing and comparing the behavior of winning and losing trades and traders, we find clear evidence of the reflection effect and the loss aversion phenomenon, which are essential in prospect theory. This work hence demonstrates an unprecedented large-scale empirical evidence of prospect theory, which has immediate implication in financial trading, e.g., developing new trading strategies by minimizing the impact of the reflection effect and the loss aversion phenomenon. Moreover, we introduce three novel behavioral metrics to differentiate winning and losing traders based on their historical trading behavior. This offers us potential opportunities to augment online social trading where traders are allowed to watch and follow the trading activities of others, by predicting potential winners based on their historical trading behavior.

  18. Prospect theory for online financial trading.

    PubMed

    Liu, Yang-Yu; Nacher, Jose C; Ochiai, Tomoshiro; Martino, Mauro; Altshuler, Yaniv

    2014-01-01

    Prospect theory is widely viewed as the best available descriptive model of how people evaluate risk in experimental settings. According to prospect theory, people are typically risk-averse with respect to gains and risk-seeking with respect to losses, known as the "reflection effect". People are much more sensitive to losses than to gains of the same magnitude, a phenomenon called "loss aversion". Despite of the fact that prospect theory has been well developed in behavioral economics at the theoretical level, there exist very few large-scale empirical studies and most of the previous studies have been undertaken with micro-panel data. Here we analyze over 28.5 million trades made by 81.3 thousand traders of an online financial trading community over 28 months, aiming to explore the large-scale empirical aspect of prospect theory. By analyzing and comparing the behavior of winning and losing trades and traders, we find clear evidence of the reflection effect and the loss aversion phenomenon, which are essential in prospect theory. This work hence demonstrates an unprecedented large-scale empirical evidence of prospect theory, which has immediate implication in financial trading, e.g., developing new trading strategies by minimizing the impact of the reflection effect and the loss aversion phenomenon. Moreover, we introduce three novel behavioral metrics to differentiate winning and losing traders based on their historical trading behavior. This offers us potential opportunities to augment online social trading where traders are allowed to watch and follow the trading activities of others, by predicting potential winners based on their historical trading behavior. PMID:25330203

  19. Prospect Theory for Online Financial Trading

    PubMed Central

    Martino, Mauro; Altshuler, Yaniv

    2014-01-01

    Prospect theory is widely viewed as the best available descriptive model of how people evaluate risk in experimental settings. According to prospect theory, people are typically risk-averse with respect to gains and risk-seeking with respect to losses, known as the “reflection effect”. People are much more sensitive to losses than to gains of the same magnitude, a phenomenon called “loss aversion”. Despite of the fact that prospect theory has been well developed in behavioral economics at the theoretical level, there exist very few large-scale empirical studies and most of the previous studies have been undertaken with micro-panel data. Here we analyze over 28.5 million trades made by 81.3 thousand traders of an online financial trading community over 28 months, aiming to explore the large-scale empirical aspect of prospect theory. By analyzing and comparing the behavior of winning and losing trades and traders, we find clear evidence of the reflection effect and the loss aversion phenomenon, which are essential in prospect theory. This work hence demonstrates an unprecedented large-scale empirical evidence of prospect theory, which has immediate implication in financial trading, e.g., developing new trading strategies by minimizing the impact of the reflection effect and the loss aversion phenomenon. Moreover, we introduce three novel behavioral metrics to differentiate winning and losing traders based on their historical trading behavior. This offers us potential opportunities to augment online social trading where traders are allowed to watch and follow the trading activities of others, by predicting potential winners based on their historical trading behavior. PMID:25330203

  20. Making better estimates of prospect reserves

    SciTech Connect

    Rose, P.R. )

    1996-01-01

    Most geoscientists predict reserve-sizes of successful exploratory prospects poorly. They are overconfident as to possible ranges of reserves; strongly overoptimistic; and therefore frequently surprised, usually on the downside. So investors suffer, and exploration staffs lose credibility. Prospect reserves (ultimate recoverable bbl/mcf) depends on three variables: Area of accumulation (ac); Average net feet of pay (ft); and Hydrocarbon-recovery factor (bbl or mcf/ac-ft). These variables are nearly always independent, and appear to be distributed lognormally. Their product, the prospect reserves distribution, commonly generated by Monte Carlo simulation, is also lognormal. Prospectors can learn to make better forecasts of prospect reserves through routine use of six different but mutually supportive estimating techniques: (1) mapping both genesis and geometry of traps employing multiple working hypotheses; (2) avoiding common psychological biases, such as [open quotes]anchoring[close quotes]; (3) constructing distributions of Area, Pay, HC-recovery, and Reserves which are constrained by the expectation of lognormality; (4) applying [open quote]reality-checks[close quote] to estimates based on (a) known analogous or parent geological situations such as field-size distributions, (b) P[sub 1%], P[sub 50%], and P[sub 99%] reserves estimates that are consequent to the proposed lognormal distribution and believable geologically; and (c) variance of reserves distribution that is consistent with that class of exploratory well, and with prospect data quality and quantity; (5) combining independent estimates by multiple seasoned explorers, who have utilized identical prospect data-sets; (6) getting [open quote]feedback[close quote] through routine comparisons of prior predictions and actual outcomes.

  1. Making better estimates of prospect reserves

    SciTech Connect

    Rose, P.R.

    1996-12-31

    Most geoscientists predict reserve-sizes of successful exploratory prospects poorly. They are overconfident as to possible ranges of reserves; strongly overoptimistic; and therefore frequently surprised, usually on the downside. So investors suffer, and exploration staffs lose credibility. Prospect reserves (ultimate recoverable bbl/mcf) depends on three variables: Area of accumulation (ac); Average net feet of pay (ft); and Hydrocarbon-recovery factor (bbl or mcf/ac-ft). These variables are nearly always independent, and appear to be distributed lognormally. Their product, the prospect reserves distribution, commonly generated by Monte Carlo simulation, is also lognormal. Prospectors can learn to make better forecasts of prospect reserves through routine use of six different but mutually supportive estimating techniques: (1) mapping both genesis and geometry of traps employing multiple working hypotheses; (2) avoiding common psychological biases, such as {open_quotes}anchoring{close_quotes}; (3) constructing distributions of Area, Pay, HC-recovery, and Reserves which are constrained by the expectation of lognormality; (4) applying {open_quote}reality-checks{close_quote} to estimates based on (a) known analogous or parent geological situations such as field-size distributions, (b) P{sub 1%}, P{sub 50%}, and P{sub 99%} reserves estimates that are consequent to the proposed lognormal distribution and believable geologically; and (c) variance of reserves distribution that is consistent with that class of exploratory well, and with prospect data quality and quantity; (5) combining independent estimates by multiple seasoned explorers, who have utilized identical prospect data-sets; (6) getting {open_quote}feedback{close_quote} through routine comparisons of prior predictions and actual outcomes.

  2. Collaborative Software Engineering: Challenges and Prospects

    NASA Astrophysics Data System (ADS)

    Mistrík, Ivan; Grundy, John; van der Hoek, André; Whitehead, Jim

    Much work is presently ongoing in collaborative software engineering research. This work is beginning to make serious inroads into our ability to more effectively practice collaborative software engineering, with best practices, processes, tools, metrics, and other techniques becoming available for day-to-day use. However, we have not yet reached the point where the practice of collaborative software engineering is routine, without surprises, and generally as optimal as possible. This chapter summarizes the main findings of this book, draws some conclusions on these findings and looks at the prospects for software engineers in dealing with the challenges of collaborative software development. The chapter ends with prospects for collaborative software engineering.

  3. 42 CFR 413.345 - Publication of Federal prospective payment rates.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... RENAL DISEASE SERVICES; OPTIONAL PROSPECTIVELY DETERMINED PAYMENT RATES FOR SKILLED NURSING FACILITIES Prospective Payment for Skilled Nursing Facilities § 413.345 Publication of Federal prospective payment...

  4. 42 CFR 413.345 - Publication of Federal prospective payment rates.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... RENAL DISEASE SERVICES; OPTIONAL PROSPECTIVELY DETERMINED PAYMENT RATES FOR SKILLED NURSING FACILITIES Prospective Payment for Skilled Nursing Facilities § 413.345 Publication of Federal prospective payment...

  5. 42 CFR 413.345 - Publication of Federal prospective payment rates.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... RENAL DISEASE SERVICES; OPTIONAL PROSPECTIVELY DETERMINED PAYMENT RATES FOR SKILLED NURSING FACILITIES Prospective Payment for Skilled Nursing Facilities § 413.345 Publication of Federal prospective payment...

  6. Lone Tree prospect area, Railroad Valley, Nevada

    SciTech Connect

    Montgomery, S.L.

    1997-02-01

    Continued exploration in the Basin and Range of Nevada has resulted in a number of small field discoveries that confirm widespread oil generation and suggest potential in local prospect settings. One such setting, the Lone Tree prospect area, lies approximately 6.5 mi (10.4 km) southwest of Grant Canyon field in Railroad Valley. Discovered in 1983, this field had produced nearly 20 million bbl of oil by June 1996, mostly from two wells. Oil is entrapped in a slide block of fractured Paleozoic strata juxtaposed against Mississippian source rocks along a detachment fault of probable early Tertiary age. Subsequent exploration has focused on attempts to identify such blocks elsewhere in east-central Nevada, particularly in Railroad and Pine Valleys. Well, gravity, and two-dimensional seismic data suggested the existence of such a block in the Lone Tree area. These data were used as a basis for a three-dimensional seismic survey. Information from this survey identified a prospect at the structural culmination of the interpreted block. The resulting well, the 13-14 Timber Mountain, was commercially unsuccessful but yielded important new data, suggesting a need to revise existing stratigraphy and structural history. In addition, a second prospect, located farther updip, was indicated.

  7. The Swedish Family: Problems, Programs and Prospects.

    ERIC Educational Resources Information Center

    Lindblom, Paul

    1986-01-01

    To clarify issues in the controversy in Sweden concerning the means and ends of family policy, this article analyzes the economic plight of Swedish families with children, elucidates the views of parents and politicians, discusses the changing role and status of women, and considers prospects for the future. Also discussed are work equality and…

  8. Prospective Teachers' View on Geography Fieldworks

    ERIC Educational Resources Information Center

    Yilmaz, Cevdet; Bilgi, Merve Gorkem

    2011-01-01

    The purposes of the study are to examine thoroughly the components to constitute individual perceptions of prospective teachers concerning important acquisitions of geography fieldworks and to facilitate its applicability as a teaching method through their own observations and suggestions, and in this context to obtain information about the nature…

  9. Carbohydrate drugs: current status and development prospect.

    PubMed

    Zhang, Yan; Wang, Fengshan

    2015-04-01

    In recent years, there has been a great effort devoted to the investigation of the roles of carbohydrates in various essential biological processes and the development of carbohydrates to therapeutic drugs. This review summarizes the carbohydrate drugs which have been recorded in several pharmacopoeias, marketed, and under development. A prospect of the future development of carbohydrate drugs is discussed as well.

  10. Prospective associations between loneliness and emotional intelligence.

    PubMed

    Wols, A; Scholte, R H J; Qualter, P

    2015-02-01

    Loneliness has been linked cross-sectionally to emotional skill deficits (e.g., Zysberg, 2012), but missing from the literature is a longitudinal examination of these relationships. The present study fills that gap by examining the prospective relationships between loneliness and emotional functioning in young adolescents in England. One hundred and ninety-six adolescents aged 11-13 years (90 females) took part in the study and completed the youth version of the Mayer-Salovey-Caruso Emotional Intelligence Test (MSCEIT-YV) and the peer-related subscale of the Loneliness and Aloneness Scale for Children and Adolescents (LACA) at two time points, which were 10 months apart. Prospective associations were obtained for male and female adolescents separately using cross-lagged statistical techniques. Our results showed prospective links between understanding and managing emotions and loneliness for both females and males. Perceiving and using emotions were prospectively linked to loneliness in males only. Possible explanations and directions for future research are discussed.

  11. Professional Leadership Aspirations of Prospective Women Teachers

    ERIC Educational Resources Information Center

    McMillin, Marvin R.

    1972-01-01

    Results of the study seem to suggest that prospective women teachers are less likely to accept a leadership role as the level of responsibility increases and after an interruption in their career. They are also less likely to accept leadership roles in professional organizations. (Author/BY)

  12. Existing and prospective blast-furnace conditions

    SciTech Connect

    I.G. Tovarovskii; V.I. Bol'shakov; V.P. Lyalyuk; A.E. Merkulov; D. V. Pinchuk

    2009-07-15

    Blast-furnace conditions are investigated by means of a multizone model. The expected performance of prospective technologies is assessed, as well as the trends in blast-furnace processes. The model permits the identification of means of overcoming practical difficulties.

  13. Continuing Bonds and Grief: A Prospective Analysis

    ERIC Educational Resources Information Center

    Boelen, Paul A.; Stroebe, Margaret S.; Schut, Henk A. W.; Zijerveld, Annemieke M.

    2006-01-01

    Using data of 56 bereaved individuals, this study examined associations of various manifestations of continuing bonds, assessed at 7-12 months post-loss, with concurrent and prospective (9 months later) symptoms of grief and depression. Among other things it was found that, independent of initial symptom levels, manifestations of continuing bonds…

  14. Flower Power: Prospects for Photosynthetic Energy

    ERIC Educational Resources Information Center

    Poole, Alan D.; Williams, Robert H.

    1976-01-01

    This report focuses on the prospects and possibilities for using biomass as an energy source for the United States. However, the greatest potential for utilizing biomass as fuel exists in energy-starved developing nations, since it appears possible to develop biomass technologies keeping capital inputs low in relation to labor inputs. (BT)

  15. Prospects of Private Education in China

    ERIC Educational Resources Information Center

    Hua, Wu

    2009-01-01

    Private education contributes a great deal to education in China, but people are confused about the prospects of teacher development, tax problems, property rights problems, remunerations, and so forth. Legal provisions stipulate that private education and public education have the same legal status and rights, but there is still a long way to go…

  16. Prospective associations between loneliness and emotional intelligence.

    PubMed

    Wols, A; Scholte, R H J; Qualter, P

    2015-02-01

    Loneliness has been linked cross-sectionally to emotional skill deficits (e.g., Zysberg, 2012), but missing from the literature is a longitudinal examination of these relationships. The present study fills that gap by examining the prospective relationships between loneliness and emotional functioning in young adolescents in England. One hundred and ninety-six adolescents aged 11-13 years (90 females) took part in the study and completed the youth version of the Mayer-Salovey-Caruso Emotional Intelligence Test (MSCEIT-YV) and the peer-related subscale of the Loneliness and Aloneness Scale for Children and Adolescents (LACA) at two time points, which were 10 months apart. Prospective associations were obtained for male and female adolescents separately using cross-lagged statistical techniques. Our results showed prospective links between understanding and managing emotions and loneliness for both females and males. Perceiving and using emotions were prospectively linked to loneliness in males only. Possible explanations and directions for future research are discussed. PMID:25576768

  17. Strategic hospital marketing responses to prospective payment.

    PubMed

    Rosko, M D; Broyles, R W

    1987-01-01

    Hospitals may respond to the revenue constraints of prospective payment by altering their patient mix. This article provided a brief overview of marketing management and suggested that hospitals might change their patient mix by employing marketing strategies designed to attract patients to its services or to attract physicians who specialize in the appropriate medical disciplines.

  18. Problems and Prospects in Foreign Language Computing.

    ERIC Educational Resources Information Center

    Pusack, James P.

    The problems and prospects of the field of foreign language computing are profiled through a survey of typical implementation, development, and research projects that language teachers may undertake. Basic concepts in instructional design, hardware, and software are first clarified. Implementation projects involving courseware evaluation, textbook…

  19. Status and Prospects for Hadron Production Experiments

    SciTech Connect

    Schroeter, Raphaeel

    2010-03-30

    The latest results from the HARP, MIPP and NA61 Hadron Production Experiments are reviewed and their implications for neutrinos physics experiments are discussed. We emphasize three neutrino sources: accelerator-based neutrino beams, advanced neutrino sources and atmospheric neutrinos. Finally, prospects from additional forthcoming hadron production measurements are presented.

  20. School Food Practices of Prospective Teachers

    ERIC Educational Resources Information Center

    Rossiter, Melissa; Glanville, Theresa; Taylor, Jennifer; Blum, Ilya

    2007-01-01

    Background: Schoolteachers can affect students' eating habits in several ways: through nutrition knowledge, positive role modeling, and avoidance of unhealthy classroom food practices. In this study, the knowledge, attitudes, and eating behaviors of prospective teachers as determinants of intended classroom food practices and the school…

  1. Testing general relativity: Progress, problems, and prospects

    NASA Technical Reports Server (NTRS)

    Shapiro, I. I.

    1971-01-01

    The results from ground-based experimental testing are presented. Prospects for improving these experiments are discussed. Radar echo time delays, perihelion advance and solar oblateness, time variation of the gravitational constant, and radio wave deflection are considered. Ground-based and spacecraft techniques are compared on an accuracy vs. cost basis.

  2. A Prospective Study of Adolescent Pregnancy.

    ERIC Educational Resources Information Center

    Hockaday, Cathy; Crase, Sedahlia Jasper; Shelley, Mack C., II; Stockdale, Dahlia F.

    2000-01-01

    Examines prospectively the characteristics contributing to adolescent pregnancy in a pregnant and comparison group of adolescents. Adolescent pregnancy in Blacks was predicted by approval of delaying a family and pursuing a career, aspirations of working, and lower educational expectations. Higher educational wishes, lower educational…

  3. Prospects in Computer Assisted Language Lessons.

    ERIC Educational Resources Information Center

    Jamieson, Joan; Chapelle, Carol

    Some prospects for development of computer-assisted language instruction in six language skill areas (grammar, communication, reading, listening, speaking, and writing) are presented. In grammar instruction, a current challenge is to improve judging of student answers, and "intelligent" computer programs that try to identify the student's…

  4. Attitude level of prospective science teachers towards assessment

    NASA Astrophysics Data System (ADS)

    Efendi, Ridwan; Rustaman, Nuryani Y.

    2016-02-01

    A descriptive study about attitude level of prospective science teachers towards assessment was conducted with the involvement of 67 prospective science teachers from four state universities in western part of the Indonesian region and middle part of Indonesia region. Data collected by using the questionnaire consisted of four aspects, id est. prospective science teachers attitude towards assessment (cognitive level of assessment, type of assessment, and criterion of evaluation), prospective science teachers instructional practice, internal difficulties that prospective science teachers experienced related to their assessment skills, and the use of assessment process of prospective science teachers. Determination of attitude level detected from prospective science teachers was carried out in descriptive statistics, in the form of respondent average values. Research finding shows that attitude level of prospective science teachers towards assessment can be categorized as "close to constructivist".

  5. Examining Job Prospects and Training for Physician's Assistants

    ERIC Educational Resources Information Center

    Kacen, Alex

    1974-01-01

    Applicants to a physician's assistant program usually must have previous experience in the health field. Forty-nine institutions offering training programs are listed and job prospects, entrance requirements, degree programs offered and long-range prospects are discussed. (MW)

  6. Technology Preview: X-Ray Fused With Magnetic Resonance During Invasive Cardiovascular Procedures

    PubMed Central

    Gutiérrez, Luis F.; de Silva, Ranil; Ozturk, Cengizhan; Sonmez, Merdim; Stine, Annette M.; Raval, Amish N.; Raman, Venkatesh K.; Sachdev, Vandana; Aviles, Ronnier J.; Waclawiw, Myron A.; McVeigh, Elliot R.; Lederman, Robert J.

    2009-01-01

    Background We have developed and validated a system for real-time X-ray fused with magnetic resonance imaging, MRI (XFM), to guide catheter procedures with high spatial precision. Our implementation overlays roadmaps—MRI-derived soft-tissue features of interest—onto conventional X-ray fluoroscopy. We report our initial clinical experience applying XFM, using external fiducial markers, electrocardiogram (ECG)-gating, and automated real-time correction for gantry and table movement. Methods This prospective case series for technical development was approved by the NHLBI Institutional Review Board and included 19 subjects. Multimodality external fiducial markers were affixed to patients’ skin before MRI, which included contrast-enhanced, 3D T1-weighted, or breath-held and ECG-gated 2D steady state free precession imaging at 1.5T. MRI-derived roadmaps were manually segmented while patients were transferred to a calibrated X-ray fluoroscopy system. Image spaces were registered using the fiducial markers and thereafter permitted unrestricted gantry rotation, table panning, and magnification changes. Static and ECG-gated MRI data were transformed from 3D to 2D to correspond with gantry and table position and combined with live X-ray images. Results Clinical procedures included graft coronary arteriography, right ventricular free-wall biopsy, and iliac and femoral artery recanalization and stenting. MRI roadmaps improved operator confidence, and in the biopsy cases, outperformed the best available alternative imaging modality. Registration errors were increased when external fiducial markers were affixed to more mobile skin positions, such as over the abdomen. Conclusion XFM using external fiducial markers is feasible during X-ray guided catheter treatments. Multimodality image fusion may prove a useful adjunct to invasive cardiovascular procedures. PMID:18022851

  7. 43 CFR 3815.2 - Prospecting and mining.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 43 Public Lands: Interior 2 2013-10-01 2013-10-01 false Prospecting and mining. 3815.2 Section... Mineral Locations in Stock Driveway Withdrawals § 3815.2 Prospecting and mining. All prospecting and mining operations shall be conducted in such manner as to cause no interference with the use of...

  8. 50 CFR 27.64 - Prospecting and mining.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 50 Wildlife and Fisheries 8 2011-10-01 2011-10-01 false Prospecting and mining. 27.64 Section 27.64 Wildlife and Fisheries UNITED STATES FISH AND WILDLIFE SERVICE, DEPARTMENT OF THE INTERIOR... Property § 27.64 Prospecting and mining. Prospecting, locating, or filing mining claims on...

  9. 43 CFR 3815.2 - Prospecting and mining.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 43 Public Lands: Interior 2 2012-10-01 2012-10-01 false Prospecting and mining. 3815.2 Section... Mineral Locations in Stock Driveway Withdrawals § 3815.2 Prospecting and mining. All prospecting and mining operations shall be conducted in such manner as to cause no interference with the use of...

  10. 43 CFR 3815.2 - Prospecting and mining.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 43 Public Lands: Interior 2 2011-10-01 2011-10-01 false Prospecting and mining. 3815.2 Section... Mineral Locations in Stock Driveway Withdrawals § 3815.2 Prospecting and mining. All prospecting and mining operations shall be conducted in such manner as to cause no interference with the use of...

  11. 50 CFR 27.64 - Prospecting and mining.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 50 Wildlife and Fisheries 9 2012-10-01 2012-10-01 false Prospecting and mining. 27.64 Section 27.64 Wildlife and Fisheries UNITED STATES FISH AND WILDLIFE SERVICE, DEPARTMENT OF THE INTERIOR... Property § 27.64 Prospecting and mining. Prospecting, locating, or filing mining claims on...

  12. 50 CFR 27.64 - Prospecting and mining.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 50 Wildlife and Fisheries 9 2013-10-01 2013-10-01 false Prospecting and mining. 27.64 Section 27.64 Wildlife and Fisheries UNITED STATES FISH AND WILDLIFE SERVICE, DEPARTMENT OF THE INTERIOR... Property § 27.64 Prospecting and mining. Prospecting, locating, or filing mining claims on...

  13. 50 CFR 27.64 - Prospecting and mining.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 50 Wildlife and Fisheries 6 2010-10-01 2010-10-01 false Prospecting and mining. 27.64 Section 27.64 Wildlife and Fisheries UNITED STATES FISH AND WILDLIFE SERVICE, DEPARTMENT OF THE INTERIOR... Property § 27.64 Prospecting and mining. Prospecting, locating, or filing mining claims on...

  14. 43 CFR 3815.2 - Prospecting and mining.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 43 Public Lands: Interior 2 2014-10-01 2014-10-01 false Prospecting and mining. 3815.2 Section... Mineral Locations in Stock Driveway Withdrawals § 3815.2 Prospecting and mining. All prospecting and mining operations shall be conducted in such manner as to cause no interference with the use of...

  15. 50 CFR 27.64 - Prospecting and mining.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 50 Wildlife and Fisheries 9 2014-10-01 2014-10-01 false Prospecting and mining. 27.64 Section 27.64 Wildlife and Fisheries UNITED STATES FISH AND WILDLIFE SERVICE, DEPARTMENT OF THE INTERIOR... Property § 27.64 Prospecting and mining. Prospecting, locating, or filing mining claims on...

  16. A Multinomial Model of Event-Based Prospective Memory

    ERIC Educational Resources Information Center

    Smith, Rebekah E.; Bayen, Ute J.

    2004-01-01

    Prospective memory is remembering to perform an action in the future. The authors introduce the 1st formal model of event-based prospective memory, namely, a multinomial model that includes 2 separate parameters related to prospective memory processes. The 1st measures preparatory attentional processes, and the 2nd measures retrospective memory…

  17. Turkish Prospective Chemistry Teachers' Alternative Conceptions about Acids and Bases

    ERIC Educational Resources Information Center

    Boz, Yezdan

    2009-01-01

    The purpose of this study was to obtain prospective chemistry teachers' conceptions about acids and bases concepts. Thirty-eight prospective chemistry teachers were the participants. Data were collected by means of an open-ended questionnaire and semi-structured interviews. Analysis of data indicated that most prospective teachers did not have…

  18. Turkish Prospective Teachers' Understanding and Misunderstanding on Global Warming

    ERIC Educational Resources Information Center

    Ocal, A.; Kisoglu, M.; Alas, A.; Gurbuz, H.

    2011-01-01

    The key objective of this study is to determine the Turkish elementary prospective teachers' opinions on global warming. It is also aimed to establish prospective teachers' views about the environmental education in Turkish universities. A true-false type scale was administered to 564 prospective teachers from science education, social studies…

  19. 25 CFR 214.29 - Prospecting; abandonment of mines.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 25 Indians 1 2013-04-01 2013-04-01 false Prospecting; abandonment of mines. 214.29 Section 214.29... RESERVATION LANDS, OKLAHOMA, FOR MINING, EXCEPT OIL AND GAS § 214.29 Prospecting; abandonment of mines. All prospecting or mining operations or the abandonment of a well or mine shall be subject to the approval of...

  20. 25 CFR 214.29 - Prospecting; abandonment of mines.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 25 Indians 1 2012-04-01 2011-04-01 true Prospecting; abandonment of mines. 214.29 Section 214.29... RESERVATION LANDS, OKLAHOMA, FOR MINING, EXCEPT OIL AND GAS § 214.29 Prospecting; abandonment of mines. All prospecting or mining operations or the abandonment of a well or mine shall be subject to the approval of...

  1. Prospective Memory in a Language-Trained Chimpanzee ("Pan Troglodytes")

    ERIC Educational Resources Information Center

    Beran, Michael J.; Perdue, Bonnie M.; Bramlett, Jessica L.; Menzel, Charles R.; Evans, Theodore A.

    2012-01-01

    Prospective memory involves the encoding, retention, and implementation of an intended future action. Although humans show many forms of prospective memory, less is known about the future oriented processes of nonhuman animals, or their ability to use prospective memory. In this experiment, a chimpanzee named Panzee, who had learned to associate…

  2. Predictors of Time-Based Prospective Memory in Children

    ERIC Educational Resources Information Center

    Mackinlay, Rachael J.; Kliegel, Matthias; Mantyla, Timo

    2009-01-01

    This study identified age differences in time-based prospective memory performance in school-aged children and explored possible cognitive correlates of age-related performance. A total of 56 7- to 12-year-olds performed a prospective memory task in which prospective memory accuracy, ongoing task performance, and time monitoring were assessed.…

  3. 25 CFR 214.29 - Prospecting; abandonment of mines.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... RESERVATION LANDS, OKLAHOMA, FOR MINING, EXCEPT OIL AND GAS § 214.29 Prospecting; abandonment of mines. All prospecting or mining operations or the abandonment of a well or mine shall be subject to the approval of the... 25 Indians 1 2014-04-01 2014-04-01 false Prospecting; abandonment of mines. 214.29 Section...

  4. 25 CFR 214.29 - Prospecting; abandonment of mines.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... RESERVATION LANDS, OKLAHOMA, FOR MINING, EXCEPT OIL AND GAS § 214.29 Prospecting; abandonment of mines. All prospecting or mining operations or the abandonment of a well or mine shall be subject to the approval of the... 25 Indians 1 2011-04-01 2011-04-01 false Prospecting; abandonment of mines. 214.29 Section...

  5. 25 CFR 214.29 - Prospecting; abandonment of mines.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... RESERVATION LANDS, OKLAHOMA, FOR MINING, EXCEPT OIL AND GAS § 214.29 Prospecting; abandonment of mines. All prospecting or mining operations or the abandonment of a well or mine shall be subject to the approval of the... 25 Indians 1 2010-04-01 2010-04-01 false Prospecting; abandonment of mines. 214.29 Section...

  6. Hydrothermal Ni Prospectivity Analysis of Tasmania, Australia

    NASA Astrophysics Data System (ADS)

    Gonzalez-Alvalez, I.; Porwal, A.; McCuaig, T. C.

    2009-04-01

    Tasmania contains the largest hydrothermal Ni deposit in Australia: Avebury (118,000 Ni metal tonnes). This Devonian deposit was discovered in 1998 in the Dundas geological region, and represents an outstanding example of hydrothermal Nickel sulphide mineralization type. Avebury Ni deposit is a system of hydrothermal Ni ore bodies. It is hosted by an intensely altered and serpentinized Cambrian ultramafic suite in close proximity to major structural features. The mineralization is considered to be the result of hydrothermal scavenging and remobilization of the original nickel content of the mafic/ultramafic rocks in the area, and subsequent re-deposition in favourable structural traps. The mineralization is spatially and temporally related to a large granitic intrusion, the Heemskirk Granite, which is considered to be the source of the hydrothermal fluids as well as the necessary thermal gradients for the circulation of the fluids. Tasmania is largely covered by the Jurassic Ferrar Continental Flood basalt Province in the East and presents early Cambrian ultramafic-mafic complexes in the West. The Ferrar large igneous province (LIP) extends over to Antarctica and is related to the Karoo Province in southern Africa that comprises tholeiitic lava flows, sills, and dyke swarms. The Ferrar and Karoo provinces were associated with the same thermal anomaly that was involved in the break up of Gondwana. The presence of mafic/ultramafic rocks in favourable lithological packages and/or structural traps along the margins of the province, as well as several prospective reduced or reactive sedimentary packages within and around the Ferrar indicate that this LIP could represent a novel promising ground for Ni hydrothermal exploration. Based on this prospective geological background, a prospectivity analysis for hydrothermal Ni deposits was carried out on regional scale for the entire state of Tasmania. A conceptual model of hydrothermal nickel mineral system was used to

  7. Transparent Meta-Analysis of Prospective Memory and Aging

    PubMed Central

    Uttl, Bob

    2008-01-01

    Prospective memory (ProM) refers to our ability to become aware of a previously formed plan at the right time and place. After two decades of research on prospective memory and aging, narrative reviews and summaries have arrived at widely different conclusions. One view is that prospective memory shows large age declines, larger than age declines on retrospective memory (RetM). Another view is that prospective memory is an exception to age declines and remains invariant across the adult lifespan. The present meta-analysis of over twenty years of research settles this controversy. It shows that prospective memory declines with aging and that the magnitude of age decline varies by prospective memory subdomain (vigilance, prospective memory proper, habitual prospective memory) as well as test setting (laboratory, natural). Moreover, this meta-analysis demonstrates that previous claims of no age declines in prospective memory are artifacts of methodological and conceptual issues afflicting prior research including widespread ceiling effects, low statistical power, age confounds, and failure to distinguish between various subdomains of prospective memory (e.g., vigilance and prospective memory proper). PMID:18286167

  8. Prospects for Inflationary B-Mode Detection

    NASA Technical Reports Server (NTRS)

    Kogut, Alan J.

    2011-01-01

    Measurements of the linear polarization of the cosmic microwave background provide a direct window into the physics of inflation. The experimental challenges are daunting: not only is the predicted signal faint compared to the photon noise limit, but it is hidden behind competing foregrounds from both local and cosmic sources. I will discuss the experimental response to these challenges and the prospects for eventual detection and characterization of the inflationary signal.

  9. Prospects and expectations for unstructured methods

    NASA Technical Reports Server (NTRS)

    Baker, Timothy J.

    1995-01-01

    The last decade has witnessed a vigorous and sustained research effort on unstructured methods for computational fluid dynamics. Unstructured mesh generators and flow solvers have evolved to the point where they are now in use for design purposes throughout the aerospace industry. In this paper we survey the various mesh types, structured as well as unstructured, and examine their relative strengths and weaknesses. We argue that unstructured methodology does offer the best prospect for the next generation of computational fluid dynamics algorithms.

  10. World transport of energy: prospects to 1995

    SciTech Connect

    Hawdon, D.

    1985-01-01

    A new edition of a report, first published in 1980, provides a detailed analysis of energy transport, the demand for energy transport services, the supply of transport capacity, freight market and reconciliation of supply and demand, and policy options and their consequences. The report covers oil, coal, natural gas and liquefied petroleum in international trade, the costs of energy transport, and an assessment of seaborne energy transport prospects to 1995.

  11. Monograph on prospective developments in oceanology

    NASA Technical Reports Server (NTRS)

    Monin, A. S.

    1986-01-01

    Excerpts from a chapter of a monograph, Oceanology in the Year 2000, which has been prepared for publication at the USSR Academy of Sciences' Institute of Oceanology, is presented. The author of this chapter is A. S. Morin, corresponding member of the USSR Academy of Sciences and director of the oceanology institute. The monograph is said to be the collective work of a group of specialists. Monin views prospective developments of oceanology and oceanology related research and development, technology and expedition research.

  12. Hydrothermal Ni Prospectivity Analysis of Tasmania, Australia

    NASA Astrophysics Data System (ADS)

    Gonzalez-Alvarez, I.; Porwal, A.; McCuaig, T. C.; Maier, W.

    2009-04-01

    Tasmania contains the largest hydrothermal Ni deposit in Australia: Avebury (118,000 Ni metal tonnes). This Devonian deposit was discovered in 1998 in the Dundas geological region, and consists of a system of hydrothermal Ni ore bodies. They are hosted by an intensely altered and serpentinized Cambrian ultramafic suite in close proximity to major structural features. The mineralization is considered to be the result of hydrothermal scavenging and remobilization of the original nickel content of mafic/ultramafic rocks in the area, and subsequent re-deposition in favourable structural traps. This is based on the low sulphur, low Cu and Platinum element content of the mineralization. The mineralization is spatially (at the edge) and temporally related to a large granitic intrusion, the Heemskirk Granite, which is considered to be the source of the hydrothermal fluids as well as the necessary thermal gradients for the circulation of the fluids. Tasmania is largely covered by the Jurassic Ferrar continental flood basalt province in the East and constrains a number of early Cambrian ultramafic-mafic complexes in the West. The Ferrar large igneous province (LIP) extends over to Antarctica and is temporally and genetically related to the Karoo igneous province in southern Africa that comprises tholeiitic lava flows, sills, and dyke swarms. The Ferrar and Karoo igneous provinces were associated with the same thermal anomaly that was responsible for the break up of eastern Gondwana at ca 180 Ma. Despite of timeframe differences between the Avebury Ni deposits and the Ferrar LIP emplacement, similar geological settings to the Avebury could be duplicated along the Ferrar LIP. The presence of mafic/ultramafic rocks in favourable lithological packages and/or structural traps along the margins of the province indicate that this LIP could represent a possible exploration target for Ni hydrothermal deposits. Based on this background, a prospectivity analysis for hydrothermal Ni

  13. A fresh pair of eyes on prospective memory monitoring.

    PubMed

    Shelton, Jill Talley; Christopher, Eddie A

    2016-08-01

    Remembering to complete one's future intentions is termed prospective memory. We employed a new eyetracking paradigm to concretely observe the impact of environmental cues on strategic monitoring within a visual prospective memory task. Participants worked on a continuous living-count task comprising images, while simultaneously being asked to respond to a prospective memory target when it appeared. Importantly, the prospective memory target appeared in a different area of the participant's visual field than did the continuous task, which is consistent with prospective memory in many real-world situations, and further allows for a clear index of strategic monitoring processes. Subtle cues in the form of semantically related images were embedded in the continuous task to prompt monitoring for the prospective memory target. Overt strategic monitoring was operationalized as the number of times participants fixated on the designated target area, and cue-driven monitoring was defined by the number of fixations on the prospective memory target region directly after fixating on a related cue. Overt strategic monitoring for the prospective memory target was directly observed for participants in the prospective memory condition, and cue-driven monitoring was also observed in these participants, since they were more likely to initiate monitoring immediately after fixating on a semantically related cue, relative to an unrelated cue. This psychophysiological approach afforded precise measurement of the strategic monitoring process and revealed how contextual cues in the environment interact with the cognitive mechanisms supporting prospective memory.

  14. Particle physics: recent successes and future prospects

    SciTech Connect

    Wojcicki, S.

    1984-12-01

    There is no doubt that as yet we do not have an ultimate theory of matter and forces in spite of the remarkable successes of the past decade. In this talk the author attempts to summarize briefly the historical background that led us to the present level of understanding, or more specifically to the standard model of particle physics. Subsequently the author describes several difficulties with this picture, continues with some possible indications of new physics, and finally ends with the discussion of the prospects for the future. 32 references.

  15. Therapeutic genome editing: prospects and challenges.

    PubMed

    Cox, David Benjamin Turitz; Platt, Randall Jeffrey; Zhang, Feng

    2015-02-01

    Recent advances in the development of genome editing technologies based on programmable nucleases have substantially improved our ability to make precise changes in the genomes of eukaryotic cells. Genome editing is already broadening our ability to elucidate the contribution of genetics to disease by facilitating the creation of more accurate cellular and animal models of pathological processes. A particularly tantalizing application of programmable nucleases is the potential to directly correct genetic mutations in affected tissues and cells to treat diseases that are refractory to traditional therapies. Here we discuss current progress toward developing programmable nuclease-based therapies as well as future prospects and challenges.

  16. Recent advances and future prospects in choroideremia

    PubMed Central

    Zinkernagel, Martin S; MacLaren, Robert E

    2015-01-01

    Choroideremia is a complex and rare disease that is frequently misdiagnosed due to its similar appearance to classic retinitis pigmentosa. Recent advances in genetic testing have identified specific genetic mutations in many retinal dystrophies, and the identification of the mutation of the CHM gene on the X chromosome 25 years ago has paved the way for gene replacement therapy with the first human trials now underway. This article reviews the epidemiological and pathological features of choroideremia and new prospects in imaging to monitor disease progression, as well as potential treatment approaches for choroideremia. PMID:26648685

  17. Recent Results and Future Prospects from MINOS

    SciTech Connect

    Paley, Jonathan M.; /Indiana U.

    2009-01-01

    The MINOS experiment uses the intense NuMI beam created at Fermilab and two magnetized tracking calorimeters, one located at Fermilab and one located 735 km away at the Soudan Mine in Minnesota, to make precise measurements of {nu}{sub {mu}} disappearance oscillation parameters. We present recent results from the first two years of NuMI beam operations, including the precise measurement of the atmospheric neutrino oscillation parameters and the search for sterile neutrinos. Future prospects for MINOS will also be discussed, including an improved limit on the {theta}{sub 13} mixing angle by searching for {nu}{sub e} appearance in the {nu}{sub {mu}} beam.

  18. Chiral xenobiotics bioaccumulations and environmental health prospectives.

    PubMed

    Hussain, Iqbal; ALOthman, Zeid A; Alwarthan, Abdulrahman A; Sanagi, Mohd Marsin; Ali, Imran

    2015-08-01

    The chiral xenobiotics are very dangerous for all of us due to the different enantioselective toxicities of the enantiomers. Besides, these have different enantioselective bioaccumulations and behaviors in our body and other organisms. It is of urgent need to understand the enantioselective bioaccumulations, toxicities, and the health hazards of the chiral xenobiotics. The present article describes the classification, sources of contamination, distribution, enantioselective bioaccumulation, and the toxicities of the chiral xenobiotics. Besides, the efforts are also made to discuss the prevention and remedial measures of the havoc of the chiral xenobiotics. The challenges of the chiral xenobiotics have also been highlighted. Finally, future prospectives are also discussed.

  19. Prospects for research on semiconductor materials surfaces

    NASA Astrophysics Data System (ADS)

    Shaw, Robert W., Jr.; Zavada, John M.; Spielvogel, Bernard F.

    1987-01-01

    The workshop, Prospects for Research on Semiconductor Materials Surfaces, was held at the Army Research Office, Research Triangle Park, N.C. on November 12, 1986. It was sponsored by ARO and organized by Robert Shaw, John Zavada, and Bernard Spielvogel. The workshop emphasized experiments to probe surface chemistry of semiconductor materials with the eventual goal of improved devices. Participants came from university, industrial, and Army laboratories and discussed current basic research activities, identified neglected research areas with high potential payoff, and developed specific research recommendations. This report provides the summary notes of the workshop.

  20. The prospects for oil prices: Revisited

    SciTech Connect

    Gately, D.

    1986-01-01

    This article reviews recent and current opinions about prospects for prices in the world market for crude oil. Two alternative views are examined: 1. the present oil glut and softness in the market is temporary, and by the 1990s the real price of oil well begin to rise again; and 2. the changes we have witnessed in the past five years - in oil demand, in non-OPEC supply, and in the power of the Organization of Petroleum-Exporting Countries (OPEC) - are permanent and irreversible. Oil will be in excess supply more or less indefinitely.

  1. CDF - Run II Status and Prospects

    SciTech Connect

    Manfred Paulini

    2003-03-17

    After a five year upgrade period, the CDF detector located at the Fermilab Tevatron Collider is back in operation taking high quality data with all subsystems functional. We report on the status of the CDF experiment in Run II and discuss the start-up of the Tevatron accelerator. First physics results from CDF are presented. We also discuss the prospects for B physics in RunII, in particular the measurements of B{sub S}{sup 0} flavour oscillations and CP violation in B decays.

  2. Levosimendan: The current situation and new prospects.

    PubMed

    Moreno, Nuno; Tavares-Silva, Marta; Lourenço, André P; Oliveira-Pinto, José; Henriques-Coelho, Tiago; Leite-Moreira, Adelino F

    2014-12-01

    Levosimendan is a pyridazinone-dinitrile derivative with positive inotropic and vasodilatory effects that has beneficial effects on myocardial performance. In previous randomized studies levosimendan improved hemodynamics and clinical course, but its effect on prognosis is still unclear. This important issue has limited its use. Although primarily used in the management of acute heart failure syndromes, this new inotropic agent may play a role in other clinical conditions. This review aims to summarize current knowledge on levosimendan and to present future prospects for the use of this drug.

  3. Therapeutic Genome Editing: Prospects and Challenges

    PubMed Central

    Cox, David Benjamin Turitz; Platt, Randall Jeffrey; Zhang, Feng

    2015-01-01

    Recent advances in the development of genome editing technologies based on programmable nucleases have significantly improved our ability to make precise changes in the genomes of eukaryotic cells. Genome editing is already broadening our ability to elucidate the contribution of genetics to disease by facilitating the creation of more accurate cellular and animal models of pathological processes. A particularly tantalizing application of programmable nucleases is the potential to directly correct genetic mutations in affected tissues and cells to treat diseases that are refractory to traditional therapies. Here we discuss current progress towards developing programmable nuclease-based therapies as well as future prospects and challenges. PMID:25654603

  4. LHCb Physics and 2010-11 prospects

    SciTech Connect

    Perazzini, Stefano

    2011-10-24

    LHCb is one of the four major experiments operating at the Large Hadron Collider, and is specifically dedicated to the measurement of CP-violation and rare decays in the beauty and charm quark sectors. By employing data from early LHC runs it is possible to assess the performance of the detector and to better understand the potential of the LHCb flavour programme. After a brief introduction of the motivations and of the relevant physics goals, the prospects about key CP-violation and rare decay measurements will be presented. Emphasis will be given to those topics where results with particular sensitivity to New Physics are expected during the 2010-11 run.

  5. Examining prospective mathematics teachers' proof processes for algebraic concepts

    NASA Astrophysics Data System (ADS)

    Güler, Gürsel; Dikici, Ramazan

    2014-05-01

    The aim of this study was to examine prospective mathematics teachers' proof processes for algebraic concepts. The study was conducted with 10 prospective teachers who were studying at the department of secondary mathematics teaching and who volunteered to participate in the study. The data were obtained via task-based clinical interviews that were conducted with the prospective teachers. The data obtained were analysed in accordance with the content analysis by focusing on the difficulties highlighted in the literature. It was observed that the difficulties prospective teachers experience in proof processes were in parallel with the difficulties highlighted in the literature.

  6. A Prospective Evaluation of Helical Tomotherapy

    SciTech Connect

    Bauman, Glenn ||. E-mail: glenn.bauman@lhsc.on.ca; Yartsev, Slav; Rodrigues, George ||; Lewis, Craig; Hammond, Alex; Perera, Francisco; Ash, Robert, Dar, A. Rashid |; Venkatesan, Varagur M. |; Yu, Edward; Lock, Michael; Battista, Jerry; Van Dyk, Jake ||; Baily, Laura; Coad, Terry C; Trenka, Kris C.; Warr, Barbara; Kron, Tomas

    2007-06-01

    Purpose: To report results from two clinical trials evaluating helical tomotherapy (HT). Methods and Materials: Patients were enrolled in one of two prospective trials of HT (one for palliative and one for radical treatment). Both an HT plan and a companion three-dimensional conformal radiotherapy (3D-CRT) plan were generated. Pretreatment megavoltage computed tomography was used for daily image guidance. Results: From September 2004 to January 2006, a total of 61 sites in 60 patients were treated. In all but one case, a clinically acceptable tomotherapy plan for treatment was generated. Helical tomotherapy plans were subjectively equivalent or superior to 3D-CRT in 95% of plans. Helical tomotherapy was deemed equivalent or superior in two thirds of dose-volume point comparisons. In cases of inferiority, differences were either clinically insignificant and/or reflected deliberate tradeoffs to optimize the HT plan. Overall imaging and treatment time (median) was 27 min (range, 16-91 min). According to a patient questionnaire, 78% of patients were satisfied to very satisfied with the treatment process. Conclusions: Helical tomotherapy demonstrated clear advantages over conventional 3D-CRT in this diverse patient group. The prospective trials were helpful in deploying this technology in a busy clinical setting.

  7. Thorium: Issues and prospects in Malaysia

    SciTech Connect

    AL-Areqi, Wadeeah M.; Majid, Amran Ab.; Sarmani, Sukiman; Bahri, Che Nor Aniza Che Zainul

    2015-04-29

    In Malaysia, thorium exists in minerals and rare earth elements production residue. The average range of thorium content in Malaysian monazite and xenotime minerals was found about 70,000 and 15,000 ppm respectively. About 2,636 tonnes of Malaysian monazite was produced for a period of 5 years (2006-2010) and based on the above data, it can be estimated that Malaysian monazite contains about 184.5 tonnes of thorium. Although thorium can become a major radiological problem to our environment, but with the significant deposit of thorium in Malaysian monazite, it has a prospect as a future alternative fuel in nuclear technology. This paper will discuss the thorium issues in Malaysia especially its long term radiological risks to public health and environment at storage and disposal stages, the prospect of exploring and producing high purity thorium from our rare earth elements minerals for future thorium based reactor. This paper also highlights the holistic approach in thorium recovery from Malaysian rare earth element production residue to reduce its radioactivity and extraction of thorium and rare earth elements from the minerals with minimum radiological impact to health and environment.

  8. African sedimentary basins - Tectonic controls on prospectivity

    SciTech Connect

    Bunter, M.A.G.; Crossley, R.; Hammill, M.; Jones, P.W.; Morgan, R.K.; Needham, D.T.; Spaargaren, F.A. )

    1991-03-01

    An important prerequisite for the evaluation of any sedimentary basin is the understanding of its regional tectonic setting. This is especially so in the underexplored regions of Africa. The majority of African sedimentary basins developed in an extensional setting although some have undergone subsequent compressional or transpressional deformation. The geometry and evolution of these basins is often influenced by basement structure. The extensional phase of basin development controls not only the distribution of syn-rift sediments but also the magnitude of post-rift regional subsidence and the preservation or removal of pre-rift sediments. This has important consequences for exploration models of syn-rift and pre-rift source rocks and reservoirs. Post-rift basin inversion and uplift provide crucial controls on the preservation of mature source rocks and quality of reservoirs. The distribution, nature, timing, and possible mechanisms of this uplift in Africa will be addressed. The hydrocarbon prospectivity of African basis appears to be highly variable although the limited exploration of some regions makes the exact extent of this variability unclear. Basins considered potentially prospective range from late Precambrian to Tertiary in age. The various tectonic controls outlined above, and criteria for the evaluation of underexplored areas, will be demonstrated by reference to basins studied by The Robertson Group. Examples described include basins from Bagon, Angola, Namibia, East Africa, Tertiary Rift and Karoo Rifts, and North Africa (Sudan, Egypt, Algeria, and Morocco).

  9. Thorium: Issues and prospects in Malaysia

    NASA Astrophysics Data System (ADS)

    AL-Areqi, Wadeeah M.; Majid, Amran Ab.; Sarmani, Sukiman; Bahri, Che Nor Aniza Che Zainul

    2015-04-01

    In Malaysia, thorium exists in minerals and rare earth elements production residue. The average range of thorium content in Malaysian monazite and xenotime minerals was found about 70,000 and 15,000 ppm respectively. About 2,636 tonnes of Malaysian monazite was produced for a period of 5 years (2006-2010) and based on the above data, it can be estimated that Malaysian monazite contains about 184.5 tonnes of thorium. Although thorium can become a major radiological problem to our environment, but with the significant deposit of thorium in Malaysian monazite, it has a prospect as a future alternative fuel in nuclear technology. This paper will discuss the thorium issues in Malaysia especially its long term radiological risks to public health and environment at storage and disposal stages, the prospect of exploring and producing high purity thorium from our rare earth elements minerals for future thorium based reactor. This paper also highlights the holistic approach in thorium recovery from Malaysian rare earth element production residue to reduce its radioactivity and extraction of thorium and rare earth elements from the minerals with minimum radiological impact to health and environment.

  10. Two prospective dosing methods for nortriptyline.

    PubMed

    Perry, P J; Browne, J L; Alexander, B; Tsuang, M T; Sherman, A D; Dunner, F J

    1984-01-01

    This study compared two prospective pharmacokinetic dosing methods to predict steady-state concentrations of nortriptyline. One method required multiple determinations of the nortriptyline plasma concentration to estimate the drug's steady-state concentration. The second method required a single nortriptyline concentration drawn at a fixed time, preferably 36 hours, following a nortriptyline test dose. The 36-hour nortriptyline plasma concentrations (NTP 36h) were substituted into the straight-line equation of Cssav = 17.2 + 3.74 (NTP 36h), where Cssav is the average steady-state concentration for a 100 mg/day dose of nortriptyline. No differences were noted between the observed steady-state nortriptyline concentration of 121 +/- 19 ng/ml, the 36-hour single-point prediction mean concentration of 121 +/- 21 ng/ml, or the multiple-point prediction mean concentration of 122 +/- 19 ng/ml. Because of the similar findings between the two methods, the clinical advantages and disadvantages of each kinetic approach are discussed to put these prospective dosing protocols into their proper perspective.

  11. 37 CFR 10.33 - Direct contact with prospective clients.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... prospective clients. 10.33 Section 10.33 Patents, Trademarks, and Copyrights UNITED STATES PATENT AND... clients. A practitioner may not solicit professional employment from a prospective client with whom the... not specifically known to need legal services of the kind provided by the practitioner in a...

  12. 47 CFR 76.940 - Prospective rate reduction.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 47 Telecommunication 4 2010-10-01 2010-10-01 false Prospective rate reduction. 76.940 Section 76.940 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) BROADCAST RADIO SERVICES MULTICHANNEL VIDEO AND CABLE TELEVISION SERVICE Cable Rate Regulation § 76.940 Prospective rate reduction....

  13. 47 CFR 76.940 - Prospective rate reduction.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 47 Telecommunication 4 2011-10-01 2011-10-01 false Prospective rate reduction. 76.940 Section 76.940 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) BROADCAST RADIO SERVICES MULTICHANNEL VIDEO AND CABLE TELEVISION SERVICE Cable Rate Regulation § 76.940 Prospective rate reduction....

  14. Motivating Inhibition--Reward Prospect Speeds up Response Cancellation

    ERIC Educational Resources Information Center

    Boehler, Carsten N.; Hopf, Jens-Max; Stoppel, Christian M.; Krebs, Ruth M.

    2012-01-01

    Reward prospect has been demonstrated to facilitate various cognitive and behavioral operations, particularly by enhancing the speed and vigor of processes linked to approaching reward. Studies in this domain typically employed task regimes in which participants' overt responses are facilitated by prospective rewards. In contrast, we demonstrate…

  15. The Development of Prospective Secondary Biology Teachers PCK

    ERIC Educational Resources Information Center

    Brown, Patrick; Friedrichsen, Patricia; Abell, Sandra

    2013-01-01

    In order to understand how prospective teachers develop knowledge for teaching, researchers must identify the types of knowledge that are integral to effective science teaching. This case study investigated how 4 prospective secondary biology teachers' science teaching orientations, knowledge of science learners, and knowledge of instructional…

  16. Conversations about the Moon with Prospective Teachers in Japan

    ERIC Educational Resources Information Center

    Suzuki, Mariko

    2003-01-01

    As an instructor in courses for prospective teachers, I am interested in my students' ideas and ways in which they reconstruct their ideas in conversations about science. In the case study presented here, I reflect upon (a) ways in which I engaged prospective teachers in thinking together about their observations of a natural phenomenon, the…

  17. Changes in How Prospective Teachers Anticipate Secondary Students' Answers

    ERIC Educational Resources Information Center

    Llinares, Salvador; Fernández, Ceneida; Sánchez-Matamoros, Gloria

    2016-01-01

    This study focuses on how prospective teachers learn about students' mathematical thinking when (1) anticipating secondary students' answers reflecting different characteristics of understanding, and (2) propose new activities in relation to the classification of quadrilaterals. The data were collected from forty-eight prospective secondary school…

  18. Prospective Primary School Teachers' Misconceptions about States of Matter

    ERIC Educational Resources Information Center

    Tatar, Erdal

    2011-01-01

    The purpose of this study was to identify prospective primary school teachers' misconceptions about the states of matter. The sample of the study was 227 fourth-year prospective primary school teachers in a Department of Primary Education in Turkey. Researcher asked from every participant to write a response to an open ended question about…

  19. A Study of Prospective Teachers' Consumption Patterns on Special Days

    ERIC Educational Resources Information Center

    Saglam, Halil Ibrahim

    2016-01-01

    The purpose of this study was to identify prospective teachers' consumption patterns on special days. The sample was comprised of 29 prospective teachers (22 females and 7 males) who studied Primary School Teaching in the Faculty of Education at Sakarya University during the 2014-2015 Academic Year. The study was designed as a phenomenological…

  20. Prospective Secondary Mathematics Teachers' Perspectives and Mathematical Knowledge for Teaching

    ERIC Educational Resources Information Center

    Karagöz-Akar, Gülseren

    2016-01-01

    This study investigated the relationship between prospective secondary mathematics teachers' perspectives and their mathematical knowledge for teaching in action. Data from two prospective teachers' practice-teachings, one in geometry and one in algebra, their lesson plans and self-reflections were analyzed with Teacher Perspectives and Knowledge…

  1. Prospective Physics Teachers' Awareness of Radiation and Radioactivity

    ERIC Educational Resources Information Center

    Tasoglu, Aslihan Kartal; Ates, Özlem; Bakaç, Mustafa

    2015-01-01

    The purpose of this study is to investigate prospective physics teachers' knowledge of and attitude towards radiation and radioactivity. Participants of this study are 56 prospective physics teachers. A questionnaire related with the knowledge about radiation and radiation fear was conducted. The results of this study showed that most of the…

  2. Investigating Prospective Teachers' Ability to Write Context-Based Problems

    ERIC Educational Resources Information Center

    Ültay, Neslihan; Donmez Usta, Necla

    2016-01-01

    Purpose: The purpose of this study is to investigate the prospective teachers' ability to write context-based problems about the concepts in radioactivity unit. Methodology: The study is carried out in a university in Turkey with 21 prospective teachers in physics, chemistry and biology in 2014-2015 fall terms. In the study, data are collected…

  3. Analyzing Perceptions of Prospective Teachers about Their Media Literacy Competencies

    ERIC Educational Resources Information Center

    Recepoglu, Ergun; Ergun, Muammer

    2013-01-01

    The purpose of this study is to analyze perceptions of prospective teachers about their media literacy competencies in terms of different variables. This is a descriptive research in the survey model which tries to detect the current situation. Study group includes 580 prospective teachers from Turkish, Primary School, Social Studies, Science,…

  4. 45 CFR 233.22 - Determining eligibility under prospective budgeting.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 45 Public Welfare 2 2010-10-01 2010-10-01 false Determining eligibility under prospective budgeting. 233.22 Section 233.22 Public Welfare Regulations Relating to Public Welfare OFFICE OF FAMILY... eligibility under prospective budgeting. In States which compute the amount of the assistance...

  5. 45 CFR 233.22 - Determining eligibility under prospective budgeting.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 45 Public Welfare 2 2011-10-01 2011-10-01 false Determining eligibility under prospective budgeting. 233.22 Section 233.22 Public Welfare Regulations Relating to Public Welfare OFFICE OF FAMILY... eligibility under prospective budgeting. In States which compute the amount of the assistance...

  6. 42 CFR 413.172 - Principles of prospective payment.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ...-Stage Renal Disease (ESRD) Services and Organ Procurement Costs § 413.172 Principles of prospective... ESRD facilities must accept the prospective payment rates established by CMS as payment in full for covered renal dialysis services as defined in § 413.171 or home dialysis services. Approved ESRD...

  7. 42 CFR 413.172 - Principles of prospective payment.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ...-Stage Renal Disease (ESRD) Services and Organ Procurement Costs § 413.172 Principles of prospective... ESRD facilities must accept the prospective payment rates established by CMS as payment in full for covered renal dialysis services as defined in § 413.171 or home dialysis services. Approved ESRD...

  8. 42 CFR 413.172 - Principles of prospective payment.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ...-Stage Renal Disease (ESRD) Services and Organ Procurement Costs § 413.172 Principles of prospective... ESRD facilities must accept the prospective payment rates established by CMS as payment in full for covered renal dialysis services as defined in § 413.171 or home dialysis services. Approved ESRD...

  9. Prospective Teachers' Problem Solving Skills and Self-Confidence Levels

    ERIC Educational Resources Information Center

    Gursen Otacioglu, Sena

    2008-01-01

    The basic objective of the research is to determine whether the education that prospective teachers in different fields receive is related to their levels of problem solving skills and self-confidence. Within the mentioned framework, the prospective teachers' problem solving and self-confidence levels have been examined under several variables.…

  10. Skill Levels of Prospective Physics Teachers on Problem Posing

    ERIC Educational Resources Information Center

    Cildir, Sema; Sezen, Nazan

    2011-01-01

    Problem posing is one of the topics which the educators thoroughly accentuate. Problem posing skill is defined as an introvert activity of a student's learning. In this study, skill levels of prospective physics teachers on problem posing were determined and their views on problem posing were evaluated. To this end, prospective teachers were given…

  11. Prospective Teachers' Perceptions on Different Aspects of Portfolio

    ERIC Educational Resources Information Center

    Ok, Ahmet; Erdogan, Mehmet

    2010-01-01

    This qualitative-case study examined how portfolio and portfolio assessment were perceived by prospective teachers. The participants were 23 prospective teachers from seven different teaching areas from a Turkish university. A semi-structured individual interview was conducted. The interview schedule included 15 open-ended questions. The main…

  12. Prospective Middle Grade Mathematics Teachers' Knowledge of Algebra for Teaching

    ERIC Educational Resources Information Center

    Huang, Rongjin; Kulm, Gerald

    2012-01-01

    This study examined prospective middle grade mathematics teachers' knowledge of algebra for teaching with a focus on knowledge for teaching the concept of function. 115 prospective teachers from an interdisciplinary program for mathematics and science middle teacher preparation at a large public university in the USA participated in a survey. It…

  13. Study of Prospective Teachers' Conceptualization of Value Preferences

    ERIC Educational Resources Information Center

    Koruklu, Nermin; Aktamis, Hilal

    2012-01-01

    The purpose of this study was to determine whether there were any changes in the conceptualization of prospective teachers' values preferences during their university studies. The research group was composed of 208 prospective teachers who were studying at Science Education, Social Science Education and Fine Arts Education at Adnan Menderes…

  14. Prospective Teachers' Beliefs about Problem Solving in Multiple Ways

    ERIC Educational Resources Information Center

    Arikan, Elif Esra

    2016-01-01

    The purpose of this study is to analyze whether prospective teachers believe solving a mathematics problem involves in using different solution methods. 60 mathematics prospective teachers who take the pedagogic training program in a state university were participated in this study. Five open-ended questions were asked. The study was carried out…

  15. 36 CFR 1005.14 - Prospecting, mining, and mineral leasing.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... mineral leasing. 1005.14 Section 1005.14 Parks, Forests, and Public Property PRESIDIO TRUST COMMERCIAL AND PRIVATE OPERATIONS § 1005.14 Prospecting, mining, and mineral leasing. Prospecting, mining, and the location of mining claims under the general mining laws and leasing under the mineral leasing laws...

  16. 36 CFR 1005.14 - Prospecting, mining, and mineral leasing.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... mineral leasing. 1005.14 Section 1005.14 Parks, Forests, and Public Property PRESIDIO TRUST COMMERCIAL AND PRIVATE OPERATIONS § 1005.14 Prospecting, mining, and mineral leasing. Prospecting, mining, and the location of mining claims under the general mining laws and leasing under the mineral leasing laws...

  17. 36 CFR 1005.14 - Prospecting, mining, and mineral leasing.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... mineral leasing. 1005.14 Section 1005.14 Parks, Forests, and Public Property PRESIDIO TRUST COMMERCIAL AND PRIVATE OPERATIONS § 1005.14 Prospecting, mining, and mineral leasing. Prospecting, mining, and the location of mining claims under the general mining laws and leasing under the mineral leasing laws...

  18. 36 CFR 1005.14 - Prospecting, mining, and mineral leasing.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... mineral leasing. 1005.14 Section 1005.14 Parks, Forests, and Public Property PRESIDIO TRUST COMMERCIAL AND PRIVATE OPERATIONS § 1005.14 Prospecting, mining, and mineral leasing. Prospecting, mining, and the location of mining claims under the general mining laws and leasing under the mineral leasing laws...

  19. 36 CFR 1005.14 - Prospecting, mining, and mineral leasing.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... mineral leasing. 1005.14 Section 1005.14 Parks, Forests, and Public Property PRESIDIO TRUST COMMERCIAL AND PRIVATE OPERATIONS § 1005.14 Prospecting, mining, and mineral leasing. Prospecting, mining, and the location of mining claims under the general mining laws and leasing under the mineral leasing laws...

  20. Prospective Chemistry Teachers' Conceptions of Chemical Thermodynamics and Kinetics

    ERIC Educational Resources Information Center

    Sozbilir, Mustafa; Pinarbasi, Tacettin; Canpolat, Nurtac

    2010-01-01

    This study aimed at identifying specifically prospective chemistry teachers' difficulties in determining the differences between the concepts of chemical thermodynamics and kinetics. Data were collected from 67 prospective chemistry teachers at Kazim Karabekir Education Faculty of Ataturk University in Turkey during 2005-2006 academic year. Data…

  1. Prospective Primary School Teachers' Perceptions on Boiling and Freezing

    ERIC Educational Resources Information Center

    Senocak, Erdal

    2009-01-01

    The aim of this study was to investigate the perceptions of prospective primary school teachers on the physical state of water during the processes of boiling and freezing. There were three stages in the investigation: First, open-ended questions concerning the boiling and freezing of water were given to two groups of prospective primary school…

  2. Innovation and design approaches within prospective ergonomics.

    PubMed

    Liem, André; Brangier, Eric

    2012-01-01

    In this conceptual article the topic of "Prospective Ergonomics" will be discussed within the context of innovation, design thinking and design processes & methods. Design thinking is essentially a human-centred innovation process that emphasises observation, collaboration, interpretation, visualisation of ideas, rapid concept prototyping and concurrent business analysis, which ultimately influences innovation and business strategy. The objective of this project is to develop a roadmap for innovation, involving consumers, designers and business people in an integrative process, which can be applied to product, service and business design. A theoretical structure comprising of Innovation perspectives (1), Worldviews supported by rationalist-historicist and empirical-idealistic dimensions (2) and Models of "design" reasoning (3) precedes the development and classification of existing methods as well as the introduction of new ones.

  3. Laser ignited engines: progress, challenges and prospects.

    PubMed

    Dearden, Geoff; Shenton, Tom

    2013-11-01

    Laser ignition (LI) has been shown to offer many potential benefits compared to spark ignition (SI) for improving the performance of internal combustion (IC) engines. This paper outlines progress made in recent research on laser ignited IC engines, discusses the potential advantages and control opportunities and considers the challenges faced and prospects for its future implementation. An experimental research effort has been underway at the University of Liverpool (UoL) to extend the stratified speed/load operating region of the gasoline direct injection (GDI) engine through LI research, for which an overview of some of the approaches, testing and results to date are presented. These indicate how LI can be used to improve control of the engine for: leaner operation, reductions in emissions, lower idle speed and improved combustion stability. PMID:24514930

  4. Prospective Memory Training: Outlining a New Approach.

    PubMed

    Waldum, Emily R; Dufault, Carolyn L; McDaniel, Mark A

    2014-12-01

    Prospective memory (PM) tasks are those that must be performed in the future (e.g., attend an appointment). While these everyday tasks can be especially relevant for older adults (i.e., medication adherence), and have been associated with age-related decline, PM has been virtually overlooked in the cognitive training domain. This article describes the first comprehensive PM training intervention. Older adults (age 55 to 75) who received training completed 8 weekly PM training sessions that consisted of variable PM training tasks, strategy-focused discussion, and homework assignments. Those assigned to a control group completed only the first and last training task. On both a real-world proxy PM transfer task and the training tasks detailed here, there was a positive impact of PM training, suggesting practical benefits of the current training package for older adults. Benefits may also extend to other special populations who experience PM impairments (e.g., traumatic brain injury [TBI], Parkinson's). PMID:25480795

  5. Prospects for Breakthrough Propulsion From Physics

    NASA Technical Reports Server (NTRS)

    Millis, Marc G.

    2004-01-01

    "Space drives", "Warp drives", and "Wormholes:" these concepts may sound like science fiction, but they are being written about in reputable journals. To assess the implications of these emerging prospects for future spaceflight, NASA supported the Breakthrough Propulsion Physics Project from 1996 through 2002. This Project has three grand challenges: (1) Discover propulsion that eliminates the need for propellant; (2) Discover methods to achieve hyper-fast travel; and (3) Discover breakthrough methods to power spacecraft. Because these challenges are presumably far from fruition, and perhaps even impossible, a special emphasis is placed on selecting incremental and affordable research that addresses the critical issues behind these challenges. Of 16 incremental research tasks completed by the project and from other sponsors, about a third were found not to be viable, a quarter have clear opportunities for sequels, and the rest remain unresolved.

  6. Future Space Transportation Technology: Prospects and Priorities

    NASA Technical Reports Server (NTRS)

    Billie, Matt; Reed, Lisa; Harris, David

    2003-01-01

    The Transportation Working Group (TWG) was chartered by the NASA Exploration Team (NEXT) to conceptualize, define, and advocate within NASA the space transportation architectures and technologies required to enable the human and robotic exploration and development of space envisioned by the NEXT. In 2002, the NEXT tasked the TWG to assess exploration space transportation requirements versus current and prospective Earth-to-Orbit (ETO) and in-space transportation systems, technologies, and research, in order to identify investment gaps and recommend priorities. The result was a study now being incorporated into future planning by the NASA Space Architect and supporting organizations. This paper documents the process used to identify exploration space transportation investment gaps, as well as the group's recommendations for closing these gaps and prioritizing areas of future investment for NASA work on advanced propulsion systems.

  7. Earth Rotation Dynamics: Review and Prospects

    NASA Technical Reports Server (NTRS)

    Chao, Benjamin F.

    2004-01-01

    Modem space geodetic measurement of Earth rotation variations, particularly by means of the VLBI technique, has over the years allowed studies of Earth rotation dynamics to advance in ever-increasing precision, accuracy, and temporal resolution. A review will be presented on our understanding of the geophysical and climatic causes, or "excitations", for length-of-day change, polar motion, and nutations. These excitations sources come from mass transports that constantly take place in the Earth system comprised of the atmosphere, hydrosphere, cryosphere, lithosphere, mantle, and the cores. In this sense, together with other space geodetic measurements of time-variable gravity and geocenter motion, Earth rotation variations become a remote-sensing tool for the integral of all mass transports, providing valuable information about the latter on a wide range of spatial and temporal scales. Future prospects with respect to geophysical studies with even higher accuracy and resolution will be discussed.

  8. Prospects of High Energy Laboratory Astrophysics

    SciTech Connect

    Ng, J.S.T.; Chen, P.; /SLAC

    2006-09-21

    Ultra high energy cosmic rays (UHECR) have been observed but their sources and production mechanisms are yet to be understood. We envision a laboratory astrophysics program that will contribute to the understanding of cosmic accelerators with efforts to: (1) test and calibrate UHECR observational techniques, and (2) elucidate the underlying physics of cosmic acceleration through laboratory experiments and computer simulations. Innovative experiments belonging to the first category have already been done at the SLAC FFTB. Results on air fluorescence yields from the FLASH experiment are reviewed. Proposed future accelerator facilities can provided unprecedented high-energy-densities in a regime relevant to cosmic acceleration studies and accessible in a terrestrial environment for the first time. We review recent simulation studies of nonlinear plasma dynamics that could give rise to cosmic acceleration, and discuss prospects for experimental investigation of the underlying mechanisms.

  9. Detection Prospects of the Cosmic Neutrino Background

    NASA Astrophysics Data System (ADS)

    Li, Yu-Feng

    The existence of the cosmic neutrino background (CνB) is a fundamental prediction of the standard Big Bang cosmology. Although current cosmological probes provide indirect observational evidence, the direct detection of the CνB in a laboratory experiment is a great challenge to the present experimental techniques. We discuss the future prospects for the direct detection of the CνB, with the emphasis on the method of captures on beta-decaying nuclei and the PTOLEMY project. Other possibilities using the electron-capture (EC) decaying nuclei, the annihilation of extremely high-energy cosmic neutrinos (EHECνs) at the Z-resonance, and the atomic de-excitation method are also discussed in this review.

  10. Detection prospects of the cosmic neutrino background

    NASA Astrophysics Data System (ADS)

    Li, Yu-Feng

    2015-04-01

    The existence of the cosmic neutrino background (CνB) is a fundamental prediction of the standard Big Bang cosmology. Although current cosmological probes provide indirect observational evidence, the direct detection of the CνB in a laboratory experiment is a great challenge to the present experimental techniques. We discuss the future prospects for the direct detection of the CνB, with the emphasis on the method of captures on beta-decaying nuclei and the PTOLEMY project. Other possibilities using the electron-capture (EC) decaying nuclei, the annihilation of extremely high-energy cosmic neutrinos (EHECνs) at the Z-resonance, and the atomic de-excitation method are also discussed in this review (talk given at the International Conference on Massive Neutrinos, Singapore, 9-13 February 2015).

  11. Laser ignited engines: progress, challenges and prospects.

    PubMed

    Dearden, Geoff; Shenton, Tom

    2013-11-01

    Laser ignition (LI) has been shown to offer many potential benefits compared to spark ignition (SI) for improving the performance of internal combustion (IC) engines. This paper outlines progress made in recent research on laser ignited IC engines, discusses the potential advantages and control opportunities and considers the challenges faced and prospects for its future implementation. An experimental research effort has been underway at the University of Liverpool (UoL) to extend the stratified speed/load operating region of the gasoline direct injection (GDI) engine through LI research, for which an overview of some of the approaches, testing and results to date are presented. These indicate how LI can be used to improve control of the engine for: leaner operation, reductions in emissions, lower idle speed and improved combustion stability.

  12. Kitasato symposium 2010: new prospects for cytokines

    PubMed Central

    2010-01-01

    The Second Kitasato Symposium: New Prospects for Cytokines brought together researchers and rheumatologists to consider the essential role of cytokines in health and their contributions to autoimmunity. Topics addressed during the Symposium - which was held in Berlin, Germany from 27 to 29 May 2010 - included established and new cytokine targets in arthritis and autoimmunity and innovative aspects of osteoimmunology as well as current perspectives from translational and clinical studies. The keynote lecture, delivered by George Kollias, focused on insights gained from animal models into the mechanisms of TNF function in chronic inflammation and autoimmunity. The presentations at the Symposium resulted in productive discussions regarding potential new targets for the treatment of rheumatoid arthritis and other autoimmune disorders. PMID:21235827

  13. Photoacoustic tomography: fundamentals, advances and prospects

    PubMed Central

    Yao, Junjie; Wang, Lihong V.

    2011-01-01

    Optical microscopy has been contributing to the development of life science for more than three centuries. However, due to strong optical scattering in tissue, its in vivo imaging ability has been restricted to studies at superficial depths. Advances in photoacoustic tomography (PAT) now allow multiscale imaging at depths from sub-millimeter to several centimeters, with spatial resolutions from sub-micrometer to sub-millimeter. Because of this high scalability and its unique optical absorption contrast, PAT is capable of performing anatomical, functional, molecular and fluid-dynamic imaging at various system levels, and is playing an increasingly important role in fundamental biological research and clinical practice. This Review discusses recent technical progress in PAT and presents corresponding applications. It ends with a discussion of several prospects and their technical challenges. PMID:22025335

  14. Magnetic mirror fusion: status and prospects

    SciTech Connect

    Post, R.F.

    1980-02-11

    Two improved mirror systems, the tandem mirror (TM) and the field-reversed mirror (FRM) are being intensively studied. The twin practical aims of these studies: to improve the economic prospects for mirror fusion power plants and to reduce the size and/or complexity of such plants relative to earlier approaches to magnetic fusion. While at the present time the program emphasis is still strongly oriented toward answering scientific questions, the emphasis is shifting as the data accumulates and as larger facilities - ones with a heavy technological and engineering orientation - are being prepared. The experimental and theoretical progress that led to the new look in mirror fusion research is briefly reviewed, the new TM and the FRM ideas are outlined, and the projected future course of mirror fusion research is discussed.

  15. Prospects of graphene electrodes in photovoltaics

    NASA Astrophysics Data System (ADS)

    Khatami, Yasin; Liu, Wei; Kang, Jiahao; Banerjee, Kaustav

    2013-09-01

    Transparent conductors (TCs) are becoming extremely popular in many different electronic applications such as touch panels, displays, light emitting devices, light sensors and solar cells. The commonly used electrode in these applications is Indium Tin Oxide (ITO). However, the cost of ITO is increasing rapidly due to the limited supply of Indium. Other issues such as lack of flexibility and cost of the deposition process make ITO less favorable in transparent electrode applications. Graphene has been under exploration as an alternative material for TC applications in the recent years. Graphene based TCs have been shown experimentally to exhibit promising electrical and optical properties. In this paper, the prospects of graphene for transparent conductors in photovoltaics are discussed. The recent advancements in this field as well as the theoretical predictions and possible pathways for improvements are presented. In the process section, we discuss methods to synthesize few-layer graphene (FLG) with high quality in a controllable manner.

  16. Rare decays experimental summary and prospects

    SciTech Connect

    Littenberg, L.

    1996-12-31

    I review the status and future prospects of searches for forbidden and highly kaon suppressed decays. This workshop comes as we are poised at the threshold of a new generation of rare K decay experiments. There are new experiments running or about to run at KEK, BNL, FNAL, and CERN. In another year or so these will be joined by the KLOE experiment at DA{Phi}NE. The good news is that it`s a very exciting time. The bad news, at least for a reviewer, is that there aren`t too many new results. Thus I`ll be giving a little more attention than usual to what the experimenters expect to do. My discussion of rare K decays covers processes that are forbidden in the Standard Model, those that highly suppressed and to a smaller extent, those that are merely discouraged.

  17. ECR ion sources: present status and prospects

    NASA Astrophysics Data System (ADS)

    Melin, G.

    1997-01-01

    Although now widely used for many applications, the electron cyclotron resonance ion sources (ECRIS), an outgrowth of the fusion plasma research, still suffer from some mystification, or at least from a lack of understanding. This article is an attempt to give a broad overview of the today ECRIS activity devoted to the production of highly charged ions: it therefore describes both physics and theory efforts, technology, performances, plans and prospects as well. An important chapter gives the status of understanding the ECRIS behavior, both the current thinking on how they operate and the experimental evidences whenever it is possible. The various existing sources, their design and main features, are then surveyed. At last the present trends of development, the potential directions for future improvement are examined.

  18. Innovation and design approaches within prospective ergonomics.

    PubMed

    Liem, André; Brangier, Eric

    2012-01-01

    In this conceptual article the topic of "Prospective Ergonomics" will be discussed within the context of innovation, design thinking and design processes & methods. Design thinking is essentially a human-centred innovation process that emphasises observation, collaboration, interpretation, visualisation of ideas, rapid concept prototyping and concurrent business analysis, which ultimately influences innovation and business strategy. The objective of this project is to develop a roadmap for innovation, involving consumers, designers and business people in an integrative process, which can be applied to product, service and business design. A theoretical structure comprising of Innovation perspectives (1), Worldviews supported by rationalist-historicist and empirical-idealistic dimensions (2) and Models of "design" reasoning (3) precedes the development and classification of existing methods as well as the introduction of new ones. PMID:22317532

  19. Prospective of 68Ga-Radiopharmaceutical Development

    PubMed Central

    Velikyan, Irina

    2014-01-01

    Positron Emission Tomography (PET) experienced accelerated development and has become an established method for medical research and clinical routine diagnostics on patient individualized basis. Development and availability of new radiopharmaceuticals specific for particular diseases is one of the driving forces of the expansion of clinical PET. The future development of the 68Ga-radiopharmaceuticals must be put in the context of several aspects such as role of PET in nuclear medicine, unmet medical needs, identification of new biomarkers, targets and corresponding ligands, production and availability of 68Ga, automation of the radiopharmaceutical production, progress of positron emission tomography technologies and image analysis methodologies for improved quantitation accuracy, PET radiopharmaceutical regulations as well as advances in radiopharmaceutical chemistry. The review presents the prospects of the 68Ga-based radiopharmaceutical development on the basis of the current status of these aspects as well as wide range and variety of imaging agents. PMID:24396515

  20. Global Prospects Rooted in Soil Science

    SciTech Connect

    Janzen, H. H.; Fixen, P.; Franzluebbers, A. J.; Hattey, J.; Izaurralde, Roberto C.; Ketterings, Q. M.; Lobb, D. A.; Schlesinger, W.

    2010-11-17

    Th e biosphere, our fragile and exquisite home, is changing abruptly and irrevocably, largely from human interference. Most or all of the coming stresses have links to the land, so fi nding hopeful outcomes depend on wide and deep understanding of soils. In this review, we pose eight urgent issues confronting humanity in coming decades: demands for food, water, nutrients, and energy; and challenges of climate change, biodiversity, “waste” reuse, and global equity. We then suggest some steps soil scientists might take to address these questions: a refocusing of research, a broadening of vision, a renewed enticement of emerging scientists, and more lucid telling of past successes and future prospects. Th e questions posed and responses posited are incomplete and not yet fully refi ned. But the conversations they elicit may help direct soil science toward greater relevance in preserving our fragile home on this changing planet.

  1. Prospective and Pavlovian mechanisms in aversive behaviour

    PubMed Central

    Rigoli, Francesco; Pezzulo, Giovanni; Dolan, Raymond J.

    2016-01-01

    Studying aversive behaviour is critical for understanding negative emotions and associated psychopathologies. However a comprehensive picture of the mechanisms underlying aversion is lacking, with associative learning theories focusing on Pavlovian reactions and decision-making theoretic approaches on prospective functions. We propose a computational model of aversion that combines goal-directed and Pavlovian forms of control into a unifying framework in which their relative importance is regulated by factors such as threat distance and controllability. Using simulations, we test whether the model can reproduce available empirical findings and discuss its relevance to understanding factors underlying negative emotions such as fear and anxiety. Furthermore, the specific method used to construct the model permits a natural mapping from its components to brain structure and function. Our model provides a basis for a unifying account of aversion that can guide empirical and interventional study contexts. PMID:26539969

  2. Investing in Prospective Cohorts for Etiologic Study of Occupational Exposures

    PubMed Central

    Blair, A.; Hines, C.J.; Thomas, K.W.; Alavanja, M.C.R.; Beane Freeman, L.E.; Hoppin, J.A.; Kamel, F.; Lynch, C.F.; Lubin, J.H.; Silverman, D.T.; Whelan, E.; Zahm, S. H.; Sandler, D. P.

    2015-01-01

    Prospective cohorts have played a major role in understanding the contribution of diet, physical activity, medical conditions, and genes to the development of many diseases, but have not been widely used for occupational exposures. Studies in agriculture are an exception. We draw upon our experience using this design to study agricultural workers to identify conditions that might foster use of prospective cohorts to study other occupational settings. Prospective cohort studies are perceived by many as the strongest epidemiologic design. It allows updating of information on exposure and other factors, collection of biologic samples before disease diagnosis for biomarker studies, assessment of effect modification by genes, lifestyle, and other occupational exposures, and evaluation of a wide range of health outcomes. Increased use of prospective cohorts would be beneficial in identifying hazardous exposures in the workplace. Occupational epidemiologists should seek opportunities to initiate prospective cohorts to investigate high priority, occupational exposures. PMID:25603935

  3. Prospective, longitudinal assessment of developmental neurotoxicity.

    PubMed Central

    Jacobson, J L; Jacobson, S W

    1996-01-01

    Methodological issues in the design of prospective, longitudinal studies of developmental neurotoxicity in humans are reviewed. A comprehensive assessment of potential confounding influences is important in these studies because inadequate assessment of confounders can threaten the validity of causal inferences drawn from the data. Potential confounders typically include demographic background variables, alcohol and smoking during pregnancy, the quality of parental stimulation, the child's age at test, and the examiner. Exposure to other substances is assessed where significant exposure is expected in the target population. In most studies, control variables even weakly related to outcome are included in all multivariate statistical analyses, and a toxic effect is inferred only if the effect of exposure is significant after controlling for the potential confounders. Once a neurotoxic effect has been identified, suspected mediating variables may be added to the analysis to examine underlying processes or mechanisms through which the exposure may impact on developmental outcome. Individual differences in vulnerability may be examined in terms of either an additive compensatory model or a synergistic "risk and resilience" approach. Failure to detect real effects (Type II error) is of particular concern in these studies because public policy considerations make it likely that negative findings will be interpreted to mean that the exposure is safe. Important sources of Type II error include inadequate representation of highly exposed individuals, overcontrol for confounders, and inappropriate correction for multiple comparisons. Given the high cost and complexity of prospective, longitudinal investigations, cross-sectional pilot studies focusing on highly exposed individuals can be valuable for the initial identification of salient domains of impairment. PMID:9182034

  4. HIGH ENERGY POLARIZATION OF BLAZARS: DETECTION PROSPECTS

    SciTech Connect

    Chakraborty, N.; Pavlidou, V.; Fields, B. D.

    2015-01-01

    Emission from blazar jets in the ultraviolet, optical, and infrared is polarized. If these low-energy photons were inverse-Compton scattered, the upscattered high-energy photons retain a fraction of the polarization. Current and future X-ray and gamma-ray polarimeters such as INTEGRAL-SPI, PoGOLITE, X-Calibur, Gamma-Ray Burst Polarimeter, GEMS-like missions, ASTRO-H, and POLARIX have the potential to discover polarized X-rays and gamma-rays from blazar jets for the first time. Detection of such polarization will open a qualitatively new window into high-energy blazar emission; actual measurements of polarization degree and angle will quantitatively test theories of jet emission mechanisms. We examine the detection prospects of blazars by these polarimetry missions using examples of 3C 279, PKS 1510-089, and 3C 454.3, bright sources with relatively high degrees of low-energy polarization. We conclude that while balloon polarimeters will be challenged to detect blazars within reasonable observational times (with X-Calibur offering the most promising prospects), space-based missions should detect the brightest blazars for polarization fractions down to a few percent. Typical flaring activity of blazars could boost the overall number of polarimetric detections by nearly a factor of five to six purely accounting for flux increase of the brightest of the comprehensive, all-sky, Fermi-LAT blazar distribution. The instantaneous increase in the number of detections is approximately a factor of two, assuming a duty cycle of 20% for every source. The detectability of particular blazars may be reduced if variations in the flux and polarization fraction are anticorrelated. Simultaneous use of variability and polarization trends could guide the selection of blazars for high-energy polarimetric observations.

  5. Mechanisms underlying the link between cannabis use and prospective memory.

    PubMed

    Cuttler, Carrie; McLaughlin, Ryan J; Graf, Peter

    2012-01-01

    While the effects of cannabis use on retrospective memory have been extensively examined, only a limited number of studies have focused on the links between cannabis use and prospective memory. We conducted two studies to examine the links between cannabis use and both time-based and event-based prospective memory as well as potential mechanisms underlying these links. For the first study, 805 students completed an online survey designed to assess cannabis consumption, problems with cannabis use indicative of a disorder, and frequency of experiencing prospective memory failures. The results showed small to moderate sized correlations between cannabis consumption, problems with cannabis use, and prospective memory. However, a series of mediation analyses revealed that correlations between problems with cannabis use and prospective memory were driven by self-reported problems with retrospective memory. For the second study, 48 non-users (who had never used cannabis), 48 experimenters (who had used cannabis five or fewer times in their lives), and 48 chronic users (who had used cannabis at least three times a week for one year) were administered three objective prospective memory tests and three self-report measures of prospective memory. The results revealed no objective deficits in prospective memory associated with chronic cannabis use. In contrast, chronic cannabis users reported experiencing more internally-cued prospective memory failures. Subsequent analyses revealed that this effect was driven by self-reported problems with retrospective memory as well as by use of alcohol and other drugs. Although our samples were not fully characterized with respect to variables such as neurological disorders and family history of substance use disorders, leaving open the possibility that these variables may play a role in the detected relationships, the present findings indicate that cannabis use has a modest effect on self-reported problems with prospective memory, with a

  6. [Echocardiographic gating in non-cardiac digital angiography].

    PubMed

    Gattoni, F; Baldini, U; Cairo, F; Nessi, R; Pozzato, C; Uslenghi, C

    1987-03-01

    This paper reports the results of the ECG-gating in non-cardiac digital subtraction angiography (DSA). One hundred and fifteen patients underwent DSA (126 examinations); ECG-gating was applied in 66/126 examinations: images recorded at 70% of R wave were subtracted. Artifacts produced by vascular movements were evaluated in all patients: only 40 examinations, carried out without ECG-gating, showed vascular artifacts. The major advantage of the ECG-gated DSA is the more efficient subtraction because of the better images superimposition: therefore, ECG-gating can be clinically helpful. On the contrary, it could be a problem in arrhythmic or bradycardic patients. ECG-gating is helpful in DSA imaging of the thoracic and abdominal aorta and of the cervical and renal arteries. In the examinations of peripheral vessels of the limbs it is not so efficient as in the trunk or in the neck.

  7. A study of geothermal prospects in the western United States

    NASA Technical Reports Server (NTRS)

    1975-01-01

    The commercial development potential of 13 underdeveloped geothermal prospects in the Western United States was examined, and the prospects were ranked in order of relative potential for development on the basis of investment considerations. The following were considered in the ranking: geotechnical and engineering data, energy market accessibility, administrative constraints, and environmental and socio-economic factors. The primary ranking criterion is the unit cost of energy production expected from each prospect. Secondary criteria are administrative constraints, environmental factors and the quality of the geotechnical data.

  8. Development of lithium-loaded liquid scintillator for PROSPECT

    NASA Astrophysics Data System (ADS)

    Norcini, Danielle; Prospect Collaboration

    2015-04-01

    The PROSPECT experiment will use a segmented detector positioned 7-20m from the High Flux Isotope Reactor core to measure the antineutrino spectrum of uranium-235 and perform a sterile neutrino search. Such measurements require the use of liquid scintillator with the capability to distinguish prompt and delayed signals from inverse beta decay events. The characterization of light yield, pulse shape discrimination performance, and neutron capture properties of the lithium-loaded scintillator have been studied with a test detector at Yale. These results will be discussed in the context of their application to antineutrino detection with the PROSPECT experiment. on behalf of the PROSPECT collaboration.

  9. The influence of strategic monitoring on the neural correlates of prospective memory.

    PubMed

    West, Robert

    2007-07-01

    The influence of strategic monitoring on the neural correlates of prospective memory was examined in two experiments. Strategic monitoring was manipulated by varying the context in which prospective cues occurred, with the cues requiring a prospective response in one task context and not the other. The N300, associated with cue detection, and the prospective positivity, associated with postretrieval processes, were elicited by prospective hits and were not elicited by prospective misses or ignore prospective cues. A parietal old-new effect was elicited by prospective misses and ignore prospective cues. Together these findings indicate that strategic monitoring may be necessary for cue detection and the recruitment of postretrieval processes, but not the recognition of a prospective cue as an old item. These findings serve to refine strategic monitoring and automatic associative accounts of prospective memory.

  10. Prospect for UV observations from the Moon

    NASA Astrophysics Data System (ADS)

    Safonova, Margarita; Mathew, Joice; Mohan, Rekhesh; Sreejith, A. G.; Murthy, Jayant; Brosch, Noah; Kappelmann, Norbert; Sharma, Arpit; Narayan, Rahul

    2014-10-01

    Space astronomy in the last 40 years has largely been done from spacecraft in low Earth orbit (LEO) for which the technology is proven and delivery mechanisms are readily available. However, new opportunities are arising with the surge in commercial aerospace missions. We describe here one such possibility: deploying a small instrument on the Moon. This can be accomplished by flying onboard the Indian entry to the Google Lunar X PRIZE competition, Team Indus mission, which is expected to deliver a nearly 30 kgs of payloads to the Moon, with a rover as its primary payload. We propose to mount a wide-field far-UV (130-180 nm) imaging telescope as a payload on the Team Indus lander. Our baseline operation is a fixed zenith pointing but with the option of a mechanism to allow observations of different attitudes. Pointing towards intermediate ecliptic latitude (50∘ or above) ensures that the Sun is at least 40∘ off the line of sight at all times. In this position, the telescope can cover higher galactic latitudes as well as parts of Galactic plane. The scientific objectives of such a prospective are delineated and discussed.

  11. Ion cyclotron emission studies: Retrospects and prospects

    NASA Astrophysics Data System (ADS)

    Gorelenkov, N. N.

    2016-05-01

    Ion cyclotron emission (ICE) studies emerged in part from the papers by A.B. Mikhailovskii published in the 1970s. Among the discussed subjects were electromagnetic compressional Alfvénic cyclotron instabilities with the linear growth rate √ {n_α /n_e } driven by fusion products, -particles which draw a lot of attention to energetic particle physics. The theory of ICE excited by energetic particles was significantly advanced at the end of the 20th century motivated by first DT experiments on TFTR and subsequent JET experimental studies which we highlight. More recently ICE theory was advanced by detailed theoretical and experimental studies on spherical torus (ST) fusion devices where the instability signals previously indistinguishable in high aspect ratio tokamaks due to high toroidal magnetic field became the subjects of experiments. We discuss further prospects of ICE theory applications for future burning plasma (BP) experiments such as those to be conducted in ITER device in France, where neutron and gamma rays escaping the plasma create extremely challenging conditions fusion alpha particle diagnostics.

  12. Neurosurgery in rural Nigeria: A prospective study

    PubMed Central

    Rabiu, Taopheeq Bamidele; Komolafe, Edward Oluwole

    2016-01-01

    Background: Africa has very few neurosurgeons. These are almost exclusively in urban centers. Consequently, people in rural areas, most of the African population, have poor or no access to neurosurgical care. We have recently pioneered rural neurosurgery in Nigeria. Objectives: This report details our initial experiences and the profile of neurosurgical admissions in our center. Methods: A prospective observational study of all neurosurgical patients managed at a rural tertiary health institution in Nigeria from December 2010 to May 2012 was done. Simple descriptive data analysis was performed. Results: A total of 249 males (75.2%) and 82 females (24.8%) were managed. The median age was 37 years (range: Day of birth – 94 years). Trauma was the leading cause of presentation with 225 (68.0%) and 35 (10.6%) having sustained head and spinal injuries, respectively. Operative intervention was performed in 54 (16.3%). Twenty-four (7.2%) patients discharged against medical advice, mostly for economic reasons. Most patients (208, 63.4%) had satisfactory outcome while 30 (9.1%) died. Conclusion: Trauma is the leading cause of rural neurosurgical presentations. There is an urgent need to improve access to adequate neurosurgical care in the rural communities.

  13. The hydroxyapatite orbital implant: a prospective study.

    PubMed

    Ashworth, J L; Rhatigan, M; Sampath, R; Brammar, R; Sunderland, S; Leatherbarrow, B

    1996-01-01

    The hydroxyapatite orbital implant was first released for use as an orbital implant in humans in August 1989. It has been shown to be well tolerated, providing good motility of the artificial eye with a low complication rate when used as a primary implant. This prospective study evaluated the hydroxyapatite orbital implant used as both a primary and a secondary implant. Sixty patients were implanted between October 1992 and November 1994, 28 being implanted as a primary procedure at the time of enucleation or evisceration, and 32 as a secondary procedure. Seven patients underwent second-stage drilling and pegging of the implant. The mean follow-up time was 13 months (range 2-26 months). A standardised operative and post-operative protocol was followed. The patients were evaluated post-operatively for the amount of enophthalmos, degree of upper lid sulcus deformity, motility of the prosthesis, location of the implant in the socket, socket status and the presence or absence of discharge, position of the drill hole and coverage of the implant. Complications and their management were documented. Both patient and surgeon made a subjective assessment of cosmesis and the patient's satisfaction with the overall result was noted. The results of this study show the hydroxyapatite orbital implant to provide excellent motility of the artificial eye and good cosmesis with a low rate of complications when used both as a primary and as a secondary implant.

  14. Innate Immunity and BK Virus: Prospective Strategies.

    PubMed

    Kariminik, Ashraf; Yaghobi, Ramin; Dabiri, Shahriar

    2016-03-01

    Recent information demonstrated that BK virus reactivation is a dominant complication after kidney transplantation, which occurs because of immunosuppression. BK virus reactivation is the main reason of transplanted kidney losing. Immune response against BK virus is the major inhibitor of the virus reactivation. Therefore, improving our knowledge regarding the main parameters that fight against BK viruses can shed light on to direct new treatment strategies to suppress BK infection. Innate immunity consists of numerous cell systems and also soluble molecules, which not only suppress virus replication, but also activate adaptive immunity to eradicate the infection. Additionally, it appears that immune responses against reactivated BK virus are the main reasons for induction of BK virus-associated nephropathy (BKAN). Thus, improving our knowledge regarding the parameters and detailed mechanisms of innate immunity and also the status of innate immunity of the patients with BK virus reactivation and its complications can introduce new prospective strategies to either prevent or as therapy of the complication. Therefore, this review was aimed to collate the most recent data regarding the roles played by innate immunity against BK virus and also the status of innate immunity in the patients with reactivation BK virus and BKAN.

  15. Hydrocarbon prospects offshore southern West Greenland

    SciTech Connect

    Chalmers, J.A.; Dahl-Jensen, T.; Bate, K.J.; Whittaker, R.C. )

    1996-01-01

    Interpretation of regional seismic data acquired in the 1990s together with a re-appraisal of the wells drilled in the 1970s has lead to an appreciation that the southern West Greenland Basin is underexplored and may contain large quantities of hydrocarbons. The regional structure and stratigraphy of the basin has been worked out. An early phase of extension, probably in the Early Cretaceous, was followed by a thermal subsidence phase in the Late Cretaceous during which thick mudstones were deposited. Renewed extension and strike-slip faulting associated with the onset of sea-floor spreading in the Labrador Sea in the Early Tertiary lead to the formation of large structures capable of trapping large quantities of hydrocarbons. Flat spots have been identified in several prospects in the Fylla Structural Complex, which is presently open for licensing, and other large structural traps exist on the Kang[cflx a]miut Ridge and in the Ikermiut area. Stratigraphic traps exist in a large syn-rift fan of mid-Cretaceous age and in Lower Tertiary basin-floor fans. All of these after structures are found in an area with an [open quotes]open-door[close quotes] licensing policy.

  16. Hydrocarbon prospects offshore southern West Greenland

    SciTech Connect

    Chalmers, J.A.; Dahl-Jensen, T.; Bate, K.J.; Whittaker, R.C.

    1996-12-31

    Interpretation of regional seismic data acquired in the 1990s together with a re-appraisal of the wells drilled in the 1970s has lead to an appreciation that the southern West Greenland Basin is underexplored and may contain large quantities of hydrocarbons. The regional structure and stratigraphy of the basin has been worked out. An early phase of extension, probably in the Early Cretaceous, was followed by a thermal subsidence phase in the Late Cretaceous during which thick mudstones were deposited. Renewed extension and strike-slip faulting associated with the onset of sea-floor spreading in the Labrador Sea in the Early Tertiary lead to the formation of large structures capable of trapping large quantities of hydrocarbons. Flat spots have been identified in several prospects in the Fylla Structural Complex, which is presently open for licensing, and other large structural traps exist on the Kang{cflx a}miut Ridge and in the Ikermiut area. Stratigraphic traps exist in a large syn-rift fan of mid-Cretaceous age and in Lower Tertiary basin-floor fans. All of these after structures are found in an area with an {open_quotes}open-door{close_quotes} licensing policy.

  17. Ion cyclotron emission studies: Retrospects and prospects

    DOE PAGES

    Gorelenkov, N. N.

    2016-06-05

    Ion cyclotron emission (ICE) studies emerged in part from the papers by A.B. Mikhailovskii published in the 1970s. Among the discussed subjects were electromagnetic compressional Alfv,nic cyclotron instabilities with the linear growth rate similar ~ √(nα/ne) driven by fusion products, -particles which draw a lot of attention to energetic particle physics. The theory of ICE excited by energetic particles was significantly advanced at the end of the 20th century motivated by first DT experiments on TFTR and subsequent JET experimental studies which we highlight. Recently ICE theory was advanced by detailed theoretical and experimental studies on spherical torus (ST) fusionmore » devices where the instability signals previously indistinguishable in high aspect ratio tokamaks due to high toroidal magnetic field became the subjects of experiments. Finally, we discuss prospects of ICE theory applications for future burning plasma (BP) experiments such as those to be conducted in ITER device in France, where neutron and gamma rays escaping the plasma create extremely challenging conditions fusion alpha particle diagnostics.« less

  18. Plasmon modes in graphene: status and prospect.

    PubMed

    Politano, Antonio; Chiarello, Gennaro

    2014-10-01

    Plasmons in graphene have unusual properties and offer promising prospects for plasmonic applications covering a wide frequency range, ranging from terahertz up to the visible. Plasmon modes have been recently studied in both free-standing and supported graphene. Here, we review plasmons in graphene with particular emphasis on plasmonic excitations in epitaxial graphene and on the influence of the underlying substrate on the screening processes. Although the theoretical comprehension of plasmons in supported graphene is still incomplete, several experimental results provide clues regarding the nature of plasmonic excitations in graphene on metals and semiconductors. Plasmon in graphene can be tuned by chemical doping and gating potentials. We show through selected examples that the adsorbates can be used to tune the plasmon frequency, while the intercalation of chemical species allows the decoupling of the graphene sheet from the substrate to recover the plasmon dispersion of pristine graphene. Finally, we also report intriguing effects due to many-body interaction, such as the excitations generated by electron-electron coupling (magnetoplasmons) and the composite modes arising from the coupling of plasmons with phonons and with charge carriers. PMID:25130215

  19. Prospective Memory, Personality, and Individual Differences

    PubMed Central

    Uttl, Bob; White, Carmela A.; Wong Gonzalez, Daniela; McDouall, Joanna; Leonard, Carrie A.

    2012-01-01

    A number of studies investigating the relationship between personality and prospective memory (ProM) have appeared during the last decade. However, a review of these studies reveals little consistency in their findings and conclusions. To clarify the relationship between ProM and personality, we conducted two studies: a meta-analysis of prior research investigating the relationships between ProM and personality, and a study with 378 participants examining the relationships between ProM, personality, verbal intelligence, and retrospective memory. Our review of prior research revealed great variability in the measures used to assess ProM, and in the methodological quality of prior research; these two factors may partially explain inconsistent findings in the literature. Overall, the meta-analysis revealed very weak correlations (rs ranging from 0.09 to 0.10) between ProM and three of the Big Five factors: Openness, Conscientiousness, and Agreeableness. Our experimental study showed that ProM performance was related to individual differences such as verbal intelligence as well as to personality factors and that the relationship between ProM and personality factors depends on the ProM subdomain. In combination, the two studies suggest that ProM performance is relatively weakly related to personality factors and more strongly related to individual differences in cognitive factors. PMID:23525147

  20. Basics and prospective of magnetic Heusler compounds

    NASA Astrophysics Data System (ADS)

    Felser, Claudia; Wollmann, Lukas; Chadov, Stanislav; Fecher, Gerhard H.; Parkin, Stuart S. P.

    2015-04-01

    Heusler compounds are a remarkable class of materials with more than 1000 members and a wide range of extraordinary multi-functionalities including halfmetallic high-temperature ferri- and ferromagnets, multi-ferroics, shape memory alloys, and tunable topological insulators with a high potential for spintronics, energy technologies, and magneto-caloric applications. The tunability of this class of materials is exceptional and nearly every functionality can be designed. Co2-Heusler compounds show high spin polarization in tunnel junction devices and spin-resolved photoemission. Manganese-rich Heusler compounds attract much interest in the context of spin transfer torque, spin Hall effect, and rare earth free hard magnets. Most Mn2-Heusler compounds crystallize in the inverse structure and are characterized by antiparallel coupling of magnetic moments on Mn atoms; the ferrimagnetic order and the lack of inversion symmetry lead to the emergence of new properties that are absent in ferromagnetic centrosymmetric Heusler structures, such as non-collinear magnetism, topological Hall effect, and skyrmions. Tetragonal Heusler compounds with large magneto crystalline anisotropy can be easily designed by positioning the Fermi energy at the van Hove singularity in one of the spin channels. Here, we give a comprehensive overview and a prospective on the magnetic properties of Heusler materials.

  1. Electrochemical metallization memories—fundamentals, applications, prospects

    NASA Astrophysics Data System (ADS)

    Valov, Ilia; Waser, Rainer; Jameson, John R.; Kozicki, Michael N.

    2011-06-01

    This review focuses on electrochemical metallization memory cells (ECM), highlighting their advantages as the next generation memories. In a brief introduction, the basic switching mechanism of ECM cells is described and the historical development is sketched. In a second part, the full spectra of materials and material combinations used for memory device prototypes and for dedicated studies are presented. In a third part, the specific thermodynamics and kinetics of nanosized electrochemical cells are described. The overlapping of the space charge layers is found to be most relevant for the cell properties at rest. The major factors determining the functionality of the ECM cells are the electrode reaction and the transport kinetics. Depending on electrode and/or electrolyte material electron transfer, electro-crystallization or slow diffusion under strong electric fields can be rate determining. In the fourth part, the major device characteristics of ECM cells are explained. Emphasis is placed on switching speed, forming and SET/RESET voltage, RON to ROFF ratio, endurance and retention, and scaling potentials. In the last part, circuit design aspects of ECM arrays are discussed, including the pros and cons of active and passive arrays. In the case of passive arrays, the fundamental sneak path problem is described and as well as a possible solution by two anti-serial (complementary) interconnected resistive switches per cell. Furthermore, the prospects of ECM with regard to further scalability and the ability for multi-bit data storage are addressed.

  2. Legume proteomics: Progress, prospects, and challenges.

    PubMed

    Rathi, Divya; Gayen, Dipak; Gayali, Saurabh; Chakraborty, Subhra; Chakraborty, Niranjan

    2016-01-01

    Legumes are the major sources of food and fodder with strong commercial relevance, and are essential components of agricultural ecosystems owing to their ability to carry out endosymbiotic nitrogen fixation. In recent years, legumes have become one of the major choices of plant research. The legume proteomics is currently represented by more than 100 reference maps and an equal number of stress-responsive proteomes. Among the 48 legumes in the protein databases, most proteomic studies have been accomplished in two model legumes, soybean, and barrel medic. This review highlights recent contributions in the field of legume proteomics to comprehend the defence and regulatory mechanisms during development and adaptation to climatic changes. Here, we attempted to provide a concise overview of the progress in legume proteomics and discuss future developments in three broad perspectives: (i) proteome of organs/tissues; (ii) subcellular compartments; and (iii) spatiotemporal changes in response to stress. Such data mining may aid in discovering potential biomarkers for plant growth, in general, apart from essential components involved in stress tolerance. The prospect of integrating proteome data with genome information from legumes will provide exciting opportunities for plant biologists to achieve long-term goals of crop improvement and sustainable agriculture.

  3. World food trends and prospects to 2025

    PubMed Central

    Dyson, Tim

    1999-01-01

    This paper reviews food (especially cereal) production trends and prospects for the world and its main regions. Despite fears to the contrary, in recent years we have seen continued progress toward better methods of feeding humanity. Sub-Saharan Africa is the sole major exception. Looking to the future, this paper argues that the continuation of recent cereal yield trends should be sufficient to cope with most of the demographically driven expansion of cereal demand that will occur until the year 2025. However, because of an increasing degree of mismatch between the expansion of regional demand and the potential for supply, there will be a major expansion of world cereal (and noncereal food) trade. Other consequences for global agriculture arising from demographic growth include the need to use water much more efficiently and an even greater dependence on nitrogen fertilizers (e.g., South Asia). Farming everywhere will depend more on information-intensive agricultural management procedures. Moreover, despite continued general progress, there still will be a significant number of undernourished people in 2025. Signs of heightened harvest variability, especially in North America, are of serious concern. Thus, although future general food trends are likely to be positive, in some respects we also could be entering a more volatile world. PMID:10339520

  4. The Leyden uranium prospect, Jefferson County, Colorado

    USGS Publications Warehouse

    Gott, Garland B.

    1950-01-01

    The Leyden uranium prospect is in sec. 28, T, 2 S., R. 70 W, Jefferson County, Cplo, Examination of the property was made in February 1950. Uranium was first reported in this locality in 1875 by Captain E. L. Berthoud, who noted uranium minerals associated with the main coal bed. The Old Leyden coal mine workings have long been abandoned and caved, but specimens of the uranium-bearing rock can be seen on the old dump 700 feet to the south. The mineralized coal bed is 10 to 12 feet thick and occurs near the base of the Laramie formation of Upper Cretaceous age. Uranium minerals are present in the form of yellow incrustations and inclusions in fractured and partly silicified coal. Petrographic studies indicate that the silica and uranium minerals were deposited after deposition and carbonization of the coal. Secondary uranium minerals also were found by C. R. Butler along the outcrop of the sandstones in the Laramie formation. No uranium minerals were found in place by the writer, but four samples from the dump contained 0.001, 0,005, 0.17 and 0.69 percent uranium.

  5. Pakistan's pattern of development and prospects.

    PubMed

    Baqui, M

    1979-01-01

    This paper analyzes past and present development experiences in Pakistan, and gives indications of possible directions for future development. Since 1969 there has been an open dissatisfaction with economic management from the government, which has resulted in a drying up of private investment. However, this drawback was partly balanced by a rapid increase in income received by Pakistanis working abroad, particularly in the Middle East. There have been slight increases in growth in agriculture, industry, and in the service sector, such as banking, insurance, and shipping. The growth of per capita income, however, is constantly offset by the acceleration in population growth, which has reached 3% a year. Literacy rate is still 19% of the total population, and basic health facilities cover only 50% of the population, while potable water supply is available to 11.2% of the rural population. Possible development directions would include the denationalization of some industries, and the creation of competition between the private and public sectors, so to improve the climate for private investment. Water availability for land irrigation should be expanded, and mineral fields better surveyed and exploited. Pakistan should develop the possibility of growing trade offered by its geographical location, improve all kinds of social services, including family planning, education, and health services, and provide the means to produce energy for all the prospected programs. PMID:12261814

  6. Tectonics and petroleum prospects in Bangladesh

    SciTech Connect

    Chowdhury, A.N.

    1995-07-10

    Bangladesh is a part of the Bengal basin, bordered to the west and northwest by Jurassic-early Cretaceous volcanic trap rocks of the Rajmahal Hills, underlain by Precambrian shield and Gondwana sediments. The Bengal basin is the largest delta basin (approximately 23,000 sq miles) in the world, at the confluence of the Ganges and Brahmaputra rivers. The deep sea fan complex that is being built outward into the Bay of Bengal has in excess of 12 km of sediments. Rate of sediment transportation within the basin, from the Himalayas and the mountains and hills to the north, east, and west, exceeds 1 billion tons/year. The tectonic and sedimentary history of Bangladesh is favorable for hydrocarbon accumulation. The basin is an underexplored region of 207,000 sq km where only 52 exploratory wells have been drilled with a success rate of more than 30%. In addition to the folded belt in the east, where gas and some oil have been found, the Garo-Rajmahal gap to the north and the deep sea fan to the south merit detailed exploration using state of the art technology. The paper describes the tectonics, sedimentation, petroleum prospects, and seismic surveys.

  7. Prospects for carbon capture and storage technologies

    SciTech Connect

    Soren Anderson; Richard Newell

    2003-01-15

    Carbon capture and storage (CCS) technologies remove carbon dioxide from flue gases for storage in geologic formations or the ocean. The study found that CCS is technically feasible and economically attractive within the range of carbon policies discussed domestically and internationally. Current costs are about $200 to $250 per ton of carbon, although costs are sensitive to fuel prices and other assumptions and could be reduced significantly through technical improvements. Near-term prospects favor CCS for certain industrial sources and electric power plants, with storage in depleted oil and gas reservoirs. Deep aquifers may provide an attractive longer-term storage option, whereas ocean storage poses greater technical and environmental uncertainty. Vast quantities of economically recoverable fossil fuels, sizable political obstacles to their abandonment, and inherent delay associated with developing alternative energy sources suggest that CCS should be seriously considered in the portfolio of options for addressing climate change, alongside energy efficiency and carbon-free energy. 61 refs., 5 figs., 5 tabs.

  8. Prospective safety performance evaluation on construction sites.

    PubMed

    Wu, Xianguo; Liu, Qian; Zhang, Limao; Skibniewski, Miroslaw J; Wang, Yanhong

    2015-05-01

    This paper presents a systematic Structural Equation Modeling (SEM) based approach for Prospective Safety Performance Evaluation (PSPE) on construction sites, with causal relationships and interactions between enablers and the goals of PSPE taken into account. According to a sample of 450 valid questionnaire surveys from 30 Chinese construction enterprises, a SEM model with 26 items included for PSPE in the context of Chinese construction industry is established and then verified through the goodness-of-fit test. Three typical types of construction enterprises, namely the state-owned enterprise, private enterprise and Sino-foreign joint venture, are selected as samples to measure the level of safety performance given the enterprise scale, ownership and business strategy are different. Results provide a full understanding of safety performance practice in the construction industry, and indicate that the level of overall safety performance situation on working sites is rated at least a level of III (Fair) or above. This phenomenon can be explained that the construction industry has gradually matured with the norms, and construction enterprises should improve the level of safety performance as not to be eliminated from the government-led construction industry. The differences existing in the safety performance practice regarding different construction enterprise categories are compared and analyzed according to evaluation results. This research provides insights into cause-effect relationships among safety performance factors and goals, which, in turn, can facilitate the improvement of high safety performance in the construction industry.

  9. eROSITA: Status and Scientific Prospects

    NASA Astrophysics Data System (ADS)

    Becker, Werner; eROSITA Team

    2016-06-01

    eROSITA (extended ROentgen Survey with an Imaging Telescope Array) is the core instrument on the Russian Spektrum-Roentgen-Gamma (SRG) mission which is currently scheduled for launch in 2017. eROSITA will perform a deep survey of the entire X-ray sky. In the soft band (0.5-2 keV), it will be about 30 times more sensitive than ROSAT, while in the hard band (2-8 keV) it will provide the first ever true imaging survey of the sky. The design driving science is the detection of large samples of galaxy clusters to redshifts z > 1 in order to study thelarge scale structure in the Universe and test cosmological models including Dark Energy. In addition, eROSITA is expected to yield a sample of a few million AGN, including obscured objects, revolutionizing our view of the evolution of supermassive black holes. The survey will also provide new insights into a wide range of astrophysical phenomena, including neutron stars and pulsars, X-ray binaries, activestars and diffuse emission from supernova remnants. The talk reports on the status of eROSITA and its scientific prospects.

  10. Prospective safety performance evaluation on construction sites.

    PubMed

    Wu, Xianguo; Liu, Qian; Zhang, Limao; Skibniewski, Miroslaw J; Wang, Yanhong

    2015-05-01

    This paper presents a systematic Structural Equation Modeling (SEM) based approach for Prospective Safety Performance Evaluation (PSPE) on construction sites, with causal relationships and interactions between enablers and the goals of PSPE taken into account. According to a sample of 450 valid questionnaire surveys from 30 Chinese construction enterprises, a SEM model with 26 items included for PSPE in the context of Chinese construction industry is established and then verified through the goodness-of-fit test. Three typical types of construction enterprises, namely the state-owned enterprise, private enterprise and Sino-foreign joint venture, are selected as samples to measure the level of safety performance given the enterprise scale, ownership and business strategy are different. Results provide a full understanding of safety performance practice in the construction industry, and indicate that the level of overall safety performance situation on working sites is rated at least a level of III (Fair) or above. This phenomenon can be explained that the construction industry has gradually matured with the norms, and construction enterprises should improve the level of safety performance as not to be eliminated from the government-led construction industry. The differences existing in the safety performance practice regarding different construction enterprise categories are compared and analyzed according to evaluation results. This research provides insights into cause-effect relationships among safety performance factors and goals, which, in turn, can facilitate the improvement of high safety performance in the construction industry. PMID:25746166

  11. Depression after CABG: a prospective study

    PubMed Central

    Nunes, Joana Kátya Veras Rodrigues Sampaio; de Figueiredo Neto, José Albuquerque; de Sousa, Rosângela Maria Lopes; Costa, Vera Lívia Xavier de Castro; Silva, Flor de Maria Araújo Mendonça; da Hora, Ana Flávia Lima Teles; da Silva, Edna Lúcia Coutinho; Reis, Lívia Mariane Castelo Branco

    2013-01-01

    Introduction Depression during or shortly after hospitalization elevated two to three times the risk of mortality or nonfatal cardiac events, significantly increasing the morbidity and mortality of these patients. Objective To assess the impact of revascularization on symptoms of depression in patients with coronary artery disease. Methods A prospective cohort study of 57 patients of both sexes undergoing coronary artery bypass grafting between June 2010 and June 2011. We used the SF-36 to assess quality of life, and the Beck Depression Inventory to detect depressive symptoms, applied preoperatively and six months. Results The prevalence of patients aged 60-69 years was 22 patients (38.60%), 39 men (68.42%), 26 described themselves as mixed race (45.61%), 16 literate (28.07 %) and 30 married (52.63%). The beck depression inventory score demonstrated increased after revascularization: 15 patients mild (26.32%) at time zero to 17 (29.82%) after. And with moderate, seven patients (12.28%) before and 10 (17.54%) after. In the categories of individuals with decreased minimum degree of 32 (56.14%) to 28 (49.12%), and severe of three (5.26%) for two (3.51%) patients. Association was observed between beck depression inventory, gender, age, lifestyle, comorbidities and quality of life. Conclusion There was a high prevalence of elevated beck depression inventory scores, lowest scores of depressive symptoms among men and association between the improvement of quality of life scores and beck depression inventory. PMID:24598954

  12. Superwarfarin poisoning in children: a prospective study.

    PubMed

    Smolinske, S C; Scherger, D L; Kearns, P S; Wruk, K M; Kulig, K W; Rumack, B H

    1989-09-01

    This prospective study was undertaken to determine the incidence, severity, time of onset, and duration of coagulopathy in children following accidental ingestion of long-acting anticoagulant rodenticides, often called "superwarfarins." Of 110 children, who ingested superwarfarins and in whom one or more prothrombin time values were obtained, 8 had a prothrombin time ratio (patient to control) of greater than or equal to 1.2, indicative of anticoagulation. Prothrombin time values obtained 48 hours after ingestion were more likely to be prolonged (6/34, 17.6%) than values obtained 24 hours after ingestion (2/104, 1.9%) (P less than .005). The occurrence of an abnormal prothrombin time could not be predicted based on the history of amount ingested or on the presence of the characteristic green-blue product dye in or around the child's mouth. Acute toxicity was evidenced by transient abdominal pain, vomiting, and heme positive stools in 2 patients. The duration of prothrombin time prolongation could not be determined because of the few values obtained after 48 hours. To detect all possible abnormal prothrombin time values, 24- and 48-hour determinations are recommended after a child has ingested a superwarfarin. PMID:2771552

  13. Prospective Memory Training: Outlining a New Approach

    PubMed Central

    Waldum, Emily R.; Dufault, Carolyn L.; McDaniel, Mark A.

    2015-01-01

    Prospective memory (PM) tasks are those that must be performed in the future (e.g., attend an appointment). While these everyday tasks can be especially relevant for older adults (i.e., medication adherence), and have been associated with age-related decline, PM has been virtually overlooked in the cognitive training domain. This article describes the first comprehensive PM training intervention. Older adults (age 55 to 75) who received training completed 8 weekly PM training sessions that consisted of variable PM training tasks, strategy-focused discussion, and homework assignments. Those assigned to a control group completed only the first and last training task. On both a real-world proxy PM transfer task and the training tasks detailed here, there was a positive impact of PM training, suggesting practical benefits of the current training package for older adults. Benefits may also extend to other special populations who experience PM impairments (e.g., traumatic brain injury [TBI], Parkinson’s). PMID:25480795

  14. Plasmon modes in graphene: status and prospect.

    PubMed

    Politano, Antonio; Chiarello, Gennaro

    2014-10-01

    Plasmons in graphene have unusual properties and offer promising prospects for plasmonic applications covering a wide frequency range, ranging from terahertz up to the visible. Plasmon modes have been recently studied in both free-standing and supported graphene. Here, we review plasmons in graphene with particular emphasis on plasmonic excitations in epitaxial graphene and on the influence of the underlying substrate on the screening processes. Although the theoretical comprehension of plasmons in supported graphene is still incomplete, several experimental results provide clues regarding the nature of plasmonic excitations in graphene on metals and semiconductors. Plasmon in graphene can be tuned by chemical doping and gating potentials. We show through selected examples that the adsorbates can be used to tune the plasmon frequency, while the intercalation of chemical species allows the decoupling of the graphene sheet from the substrate to recover the plasmon dispersion of pristine graphene. Finally, we also report intriguing effects due to many-body interaction, such as the excitations generated by electron-electron coupling (magnetoplasmons) and the composite modes arising from the coupling of plasmons with phonons and with charge carriers.

  15. Prospects of Stem Cells for Retinal Diseases.

    PubMed

    Ng, Tsz Kin; Lam, Dennis S C; Cheung, Herman S

    2013-01-01

    Retinal diseases, including glaucoma, retinitis pigmentosa, diabetic retinopathy, and age-related macular degeneration, are the leading causes of irreversible visual impairment and blindness in developed countries. Traditional and current treatment regimens are based on surgical or medical interventions to slow down the disease progression. However, the number of retinal cells would continue to diminish, and the diseases could not be completely cured. There is an emerging role of stem cells in retinal research. The stem cell therapy on retinal diseases is based on 2 theories: cell replacement therapy and neuroprotective effect. The former hypothesizes that new retinal cells could be regenerated from stem cells to substitute the damaged cells in the diseased retina, whereas the latter believes that the paracrine effects of stem cells modulate the microenvironments of the diseased retina so as to protect the retinal neurons. This article summarizes the choice of stem cells in retinal research. Moreover, the current progress of retinal research on stem cells and the clinical applications of stem cells on retinal diseases are reviewed. In addition, potential challenges and future prospects of retinal stem cell research are discussed.

  16. Basics and prospective of magnetic Heusler compounds

    SciTech Connect

    Felser, Claudia Wollmann, Lukas; Chadov, Stanislav; Fecher, Gerhard H.; Parkin, Stuart S. P.

    2015-04-01

    Heusler compounds are a remarkable class of materials with more than 1000 members and a wide range of extraordinary multi-functionalities including halfmetallic high-temperature ferri- and ferromagnets, multi-ferroics, shape memory alloys, and tunable topological insulators with a high potential for spintronics, energy technologies, and magneto-caloric applications. The tunability of this class of materials is exceptional and nearly every functionality can be designed. Co{sub 2}-Heusler compounds show high spin polarization in tunnel junction devices and spin-resolved photoemission. Manganese-rich Heusler compounds attract much interest in the context of spin transfer torque, spin Hall effect, and rare earth free hard magnets. Most Mn{sub 2}-Heusler compounds crystallize in the inverse structure and are characterized by antiparallel coupling of magnetic moments on Mn atoms; the ferrimagnetic order and the lack of inversion symmetry lead to the emergence of new properties that are absent in ferromagnetic centrosymmetric Heusler structures, such as non-collinear magnetism, topological Hall effect, and skyrmions. Tetragonal Heusler compounds with large magneto crystalline anisotropy can be easily designed by positioning the Fermi energy at the van Hove singularity in one of the spin channels. Here, we give a comprehensive overview and a prospective on the magnetic properties of Heusler materials.

  17. Developing prospective managers. Part 3. The results.

    PubMed

    del Bueno, D J; Sheridan, D R

    1984-06-01

    Can managers be made? Can nurses with limited clinical experience become successful managers? Is there an objective process that can reliably predict success of applicants in a management development program? Is it possible to objectively measure and evaluate managerial skill? In this project, one candidate was successful in meeting the management training objectives; one was not. The only variables shared by both candidates were gender (both female) and 1 year of clinical nursing experience. One of the aims of the project was to identify any relationship between amount of clinical experience and success as a potential manager. As previously stressed, a sample of two participants is not sufficient to come to any reliable conclusions about this or the the other questions. However, since one candidate did meet the objectives for competent performance, we can say that an individual may not need to have several years of clinical experience for a beginning management position. Being an effective manager depends on many qualities, relationships, and values. Managing effectively is a complex interpersonal process that often is hard if not impossible to quantify or qualify. Experience with the Prospective Manager Project applicants and the participants gives us some reason to believe that, although we cannot answer these questions with a resounding unqualified "yes", we can say that it would seem possible to answer in the positive, and that future trials and experiences will provide more absolute answers to these important questions. PMID:6563065

  18. Neurosurgery in rural Nigeria: A prospective study

    PubMed Central

    Rabiu, Taopheeq Bamidele; Komolafe, Edward Oluwole

    2016-01-01

    Background: Africa has very few neurosurgeons. These are almost exclusively in urban centers. Consequently, people in rural areas, most of the African population, have poor or no access to neurosurgical care. We have recently pioneered rural neurosurgery in Nigeria. Objectives: This report details our initial experiences and the profile of neurosurgical admissions in our center. Methods: A prospective observational study of all neurosurgical patients managed at a rural tertiary health institution in Nigeria from December 2010 to May 2012 was done. Simple descriptive data analysis was performed. Results: A total of 249 males (75.2%) and 82 females (24.8%) were managed. The median age was 37 years (range: Day of birth – 94 years). Trauma was the leading cause of presentation with 225 (68.0%) and 35 (10.6%) having sustained head and spinal injuries, respectively. Operative intervention was performed in 54 (16.3%). Twenty-four (7.2%) patients discharged against medical advice, mostly for economic reasons. Most patients (208, 63.4%) had satisfactory outcome while 30 (9.1%) died. Conclusion: Trauma is the leading cause of rural neurosurgical presentations. There is an urgent need to improve access to adequate neurosurgical care in the rural communities. PMID:27695224

  19. Prehospital airway management: A prospective case study.

    PubMed

    Wilbers, N E R; Hamaekers, A E W; Jansen, J; Wijering, S C; Thomas, O; Wilbers-van Rens, R; van Zundert, A A J

    2011-01-01

    We conducted a one-year prospective study involving a prehospital Emergency Medical Service in the Netherlands to investigate the incidence of failed or difficult prehospital endotracheal intubation. During the study period the paramedics were asked to fill in a registration questionnaire after every endotracheal intubation. Of the 26,271 patient contacts, 256 endotracheal intubations were performed by paramedics in one year. Endotracheal intubation failed in 12 patients (4.8%). In 12.0% of 249 patients, a Cormack and Lehane grade III laryngoscopy was reported and a grade IV laryngoscopy was reported in 10.4%. The average number of endotracheal intubations per paramedic in one year was 4.2 and varied from zero to a maximum of 12. The median time between arrival on the scene and a positive capnograph was 7 min.38 s in the case of a Cormack and Lehane grade I laryngoscopy and 14 min.58 s in the case of a Cormack and Lehane grade 4 laryngoscopy. The incidence of endotracheal intubations performed by Dutch paramedics in one year was low, but endotracheal intubation was successful in 95.2%, which is comparable with findings in international literature. Early capnography should be used consistently in prehospital airway management. PMID:21612142

  20. Pakistan's pattern of development and prospects.

    PubMed

    Baqui, M

    1979-01-01

    This paper analyzes past and present development experiences in Pakistan, and gives indications of possible directions for future development. Since 1969 there has been an open dissatisfaction with economic management from the government, which has resulted in a drying up of private investment. However, this drawback was partly balanced by a rapid increase in income received by Pakistanis working abroad, particularly in the Middle East. There have been slight increases in growth in agriculture, industry, and in the service sector, such as banking, insurance, and shipping. The growth of per capita income, however, is constantly offset by the acceleration in population growth, which has reached 3% a year. Literacy rate is still 19% of the total population, and basic health facilities cover only 50% of the population, while potable water supply is available to 11.2% of the rural population. Possible development directions would include the denationalization of some industries, and the creation of competition between the private and public sectors, so to improve the climate for private investment. Water availability for land irrigation should be expanded, and mineral fields better surveyed and exploited. Pakistan should develop the possibility of growing trade offered by its geographical location, improve all kinds of social services, including family planning, education, and health services, and provide the means to produce energy for all the prospected programs.

  1. The 'baseball' orbital implant: a prospective study.

    PubMed

    Leatherbarrow, B; Kwartz, J; Sunderland, S; Brammar, R; Nichol, E

    1994-01-01

    The 'baseball' orbital implant was described by Frueh and Felker in 1976. Although this implant was originally described for use as a secondary implant, it has also been widely used as a primary implant at the time of enucleation. This prospective study evaluated the effectiveness of this implant used both primarily and secondarily. Forty-four patients were implanted between April 1990 and May 1991, 19 of the implants being primary and 25 secondary. A standardised operative and post-operative protocol was followed. The mean follow-up time was 31 months (range 24-36 months). The patients were evaluated for the degree of volume replacement, implant and associated prosthesis motility, secondary eyelid and socket problems, patient satisfaction, the need for further surgery and post-operative complications. The overall results achieved by primary implantation were superior to those of secondary implantation. Our results suggest that this implant provides a satisfactory functional and cosmetic rehabilitation of the anophthalmic patient with few complications.

  2. PROSPECTS FOR THE DETECTION OF INTERSTELLAR CYANOVINYLIDENE

    SciTech Connect

    Kolos, Robert; Gronowski, Marcin; Dobrowolski, Jan Cz.

    2009-08-10

    Prospects for the presence and detection of interstellar cyanovinylidene, CC(H)CN, a Y-shaped isomer of cyanoacetylene, are discussed. It is proposed that CC(H)CN can arise in interstellar clouds as one of the HC{sub 3}NH{sup +} + e {sup -} dissociative recombination products, by rearrangements of the neutral chain radical HC{sub 3}NH into branched species HCCC(H)N, CC(H)C(H)N, and/or HCC(H)CN, and by the subsequent elimination of a hydrogen atom. It is deduced that the abundance of cyanovinylidene in molecular clouds should be confined between the abundances of its chain isomers HNCCC and HCNCC. Quantum chemical predictions regarding cyanovinylidene geometry, ground-state rotational constants, centrifugal distortion constants, spin-orbit coupling, IR absorption spectroscopy, and electric dipole moment are given. The spectroscopically observed molecules formyl cyanide, NC{sub 2}(H)O, and propynal, HC{sub 3}(H)O, with structures qualitatively resembling cyanovinylidene, served to prove the adequacy of the calculational procedures employed.

  3. Status and prospects of the SNO+ experiment

    NASA Astrophysics Data System (ADS)

    Maneira, J.

    2016-05-01

    The SNO+ experiment is located at the SNOLAB underground laboratory and will employ 780 tons of liquid scintillator loaded, in its initial phase, with 800 kg of 130Te (0.3% by mass) for a low-background and high-isotope-mass search for neutrino-less double beta decay. SNO+ reuses the acrylic vessel and PMT array of the SNO detector, but several experimental upgrades and adaptations were necessary to allow for the use of liquid scintillator. The SNO+ technique allows a staged approach, and extensive R&D is ongoing to increase the loadings and improve the purification of Tellurium. The very good conditions of background and low energy threshold allow SNO+ to also have other physics topics in its program, including geo- and reactor neutrinos, Supernova and solar neutrinos. This talk will describe the main advantages and challenges of the SNO+ approach for the double-beta decay program, the current status of the experiment and its sensitivity prospects.

  4. Ossiculoplasty: A Prospective Study of 80 Cases

    PubMed Central

    Chavan, Shrinivas Shripatrao; Jain, Prateek V; Vedi, Jeevan N; Rai, Dharmendra kumar; Kadri, Himayat

    2014-01-01

    Introduction: The use of ossicular graft material in ossicular chain reconstruction has significantly improved hearing results hearing after tympanoplasty and tympanomastoid surgery for chronic otitis media. Today, otologists have a wide array of tools from which to choose, but may find it difficult to know which middle ear implant works best. Materials and Methods: A prospective study of 80 patients who underwent ossiculoplasty was performed in the ear, nose, and throat (ENT) department at a tertiary health care facility from 2011 to 2013. Patients with chronic suppurative otitis media with an air-bone gap (ABG) of >25 dB with ossicular involvement were included in the study. Total ossicular replacement prosthesis (TORP), partial ossicular replacement prosthesis (PORP), and refashioned incus were used. Success was defined as ABG <25 dB on postoperative Day 90. Results: The majority patients were of middle age with moderate conductive hearing loss. Incus was the most susceptible ossicle. Overall success rate in this study was 80.0% with an average change of 15.76 dB in ABG. Conclusion: With continuing advances in our understanding of middle ear mechanics, the results of ossiculoplasty are improving and results can be very rewarding in experienced hands. Severity of preoperative ear discharge, preoperative mastoid cellularity, presence of disease, and surgical procedure proved to be significant prognostic factors. Autograft incus and PORP fared better when the malleus handle was present while TORP gave better results when the malleus handle was eroded. PMID:25009804

  5. Uterus transplantation: current progress and future prospects.

    PubMed

    Johannesson, Liza; Järvholm, Stina

    2016-01-01

    Even if reproductive medicine has been remarkably successful during the past few decades, with the introduction of in vitro fertilization in the late 1970s and intracytoplasmic sperm injection in the early 1990s, it has been repeatedly mocked by infertility due to an absolute uterine factor. No treatment has been available for the women suffering from an absent or dysfunctional uterus, in terms of carrying a pregnancy. Approximately one in 500 women suffer from absolute uterine infertility, and the option so far to become a mother has been to either adopt or utilize gestational surrogacy. As of today, a total of eleven cases of human uterus transplantations have been reported worldwide, conducted in three different countries. The results of these initial experimental cases far exceed what might be expected of a novel surgical method. Many more uterus transplantations are to be expected in the near future, as other research teams' preparations are being ready to be put into clinical practice. In this review, we summarize the current worldwide experience of uterus transplantation as a treatment of absolute uterine factor infertility and the future prospects of human uterus transplantation. PMID:26917976

  6. Uterus transplantation: current progress and future prospects

    PubMed Central

    Johannesson, Liza; Järvholm, Stina

    2016-01-01

    Even if reproductive medicine has been remarkably successful during the past few decades, with the introduction of in vitro fertilization in the late 1970s and intracytoplasmic sperm injection in the early 1990s, it has been repeatedly mocked by infertility due to an absolute uterine factor. No treatment has been available for the women suffering from an absent or dysfunctional uterus, in terms of carrying a pregnancy. Approximately one in 500 women suffer from absolute uterine infertility, and the option so far to become a mother has been to either adopt or utilize gestational surrogacy. As of today, a total of eleven cases of human uterus transplantations have been reported worldwide, conducted in three different countries. The results of these initial experimental cases far exceed what might be expected of a novel surgical method. Many more uterus transplantations are to be expected in the near future, as other research teams’ preparations are being ready to be put into clinical practice. In this review, we summarize the current worldwide experience of uterus transplantation as a treatment of absolute uterine factor infertility and the future prospects of human uterus transplantation. PMID:26917976

  7. Prospective memory impairment in mild cognitive impairment: an analytical review.

    PubMed

    Costa, Alberto; Caltagirone, Carlo; Carlesimo, Giovanni Augusto

    2011-12-01

    Mild cognitive impairment (MCI) is a heterogeneous condition characterized by the presence in an otherwise healthy elderly individual of cognitive deficits involving specific domains in the absence of significant functional impairments. Reports indicate that prospective memory (PM), that is, the ability to remember to execute delayed intentions, is impaired in individuals with MCI. The present review discusses the current debate in the literature on PM functioning in MCI by focusing on the relationship between prospective retrieval and retrospective memory functioning. Analysis of the reported evidence revealed that both the prospective component and the retrospective component of PM can be impaired in MCI. Declarative memory dysfunction may account for the retrospective memory impairment, while either reduced executive abilities or a deficit of reflexive mechanisms could explain the prospective component impairment.

  8. [Progress and prospect of biodiesel industry in China].

    PubMed

    Li, Yang; Zeng, Jing; Du, Wei; Liu, Dehua

    2015-06-01

    The development of biodiesel and production feedstock in China was introduced, and the biodiesel production technologies as well as corresponding representative enterprises were reviewed. In addition, the development prospect of biodiesel industry in China was addressed.

  9. A Prospective Randomized Trial of Two Different Prostate Biopsy Schemes

    ClinicalTrials.gov

    2016-07-03

    Prostate Cancer; Local Anesthesia; Prostate-Specific Antigen/Blood; Biopsy/Methods; Image-guided Biopsy/Methods; Prostatic Neoplasms/Diagnosis; Prostate/Pathology; Prospective Studies; Humans; Male; Ultrasonography, Interventional/Methods

  10. Prospects of Brand Choice Behavior Research from Cognitive Perspective

    NASA Astrophysics Data System (ADS)

    Wang, Xiaohui; Lin, Lin

    The article reviews relevant literature at home and abroad on consumer brand choice behavior and summarizes the study evolution of consumer brand choice behavior, and puts forward view on relevant research prospects from cognitive perspective in this field.

  11. [PHYTOSAPONINS OF DIOSCOREA: PROSPECTS FOR APPLICATION IN WOMEN].

    PubMed

    Fedotoval, Yu O; Shleikin, A G

    2016-01-01

    This literature review is focused on findings concerning the pharmacological effects of Dioscorea phytosaponins (DPSs) on female organism. Expediency and prospects of developing DPS preparations for the treatment of mnestic and metabolic disorders accompanying climacteric syndrome are assessed.

  12. Slower, colder, longer : prospects for a very cold neutron source.

    SciTech Connect

    Micklich, B. J.; Carpenter, J. M.; Intense Pulsed Neutron Source

    2007-01-01

    The motivation for our study is to establish the prospects for a neutron source providing intense pulsed beams with spectra as cold as is realistic. The scientific motivation is to serve applications in nanoscience, biology and technology.

  13. Characterizing and validating the PROSPECT segmented scintillator detector design

    NASA Astrophysics Data System (ADS)

    Norcini, Danielle; Prospect Collaboration

    2016-03-01

    The PROSPECT experiment will use two segmented liquid scintillator detectors positioned 7-20m from the High Flux Isotope Reactor (HFIR) core to perform a search for eV-scale sterile neutrinos and measure the antineutrino spectrum of uranium-235. A multi-year R&D program focused on background studies at the HFIR reactor, lithium-loaded liquid scintillator development, and characterization of multiple prototype detectors has culminated in the design of a segmented, 3-ton liquid scintillator detector for PROSPECT Phase I. This detector design is being validated with a 50 liter, 2-segment prototype detector, PROSPECT-50. We will report results of on-going performance and calibration studies and discuss implications for the PROSPECT physics program.

  14. How important is importance for prospective memory? A review

    PubMed Central

    Walter, Stefan; Meier, Beat

    2014-01-01

    Forgetting to carry out an intention as planned can have serious consequences in everyday life. People sometimes even forget intentions that they consider as very important. Here, we review the literature on the impact of importance on prospective memory performance. We highlight different methods used to manipulate the importance of a prospective memory task such as providing rewards, importance relative to other ongoing activities, absolute importance, and providing social motives. Moreover, we address the relationship between importance and other factors known to affect prospective memory and ongoing task performance such as type of prospective memory task (time-, event-, or activity-based), cognitive loads, and processing overlaps. Finally, we provide a connection to motivation, we summarize the effects of task importance and we identify important venues for future research. PMID:25018743

  15. An investigation into prospective memory in children with developmental dyslexia

    PubMed Central

    Khan, Azizuddin

    2014-01-01

    Developmental dyslexia hinders reading and writing acquisition of around 5–10% of the children all over the world. However, little is known about role of prospective memory among dyslexics. Prospective memory is realization of delayed intention. Realization of delayed intention requires self initiated process. The present study explored the role of memory (prospective and retrospective memory), meta-memory and attention among dyslexic's children. One hundred and fifteen children (51 dyslexics and 64 normal controls) participated in the study. Prospective and retrospective memory questionnaire, everyday attention questionnaire and meta-memory were administered on children. Analysis of variance was used to analyses the data. All the main effects were significant. Some interactions were also found to be significant. Results suggest that dyslexic's performance on memory (prospective and retrospective memory) was worse than normal control. Meta-memory influences both dyslexics and normal control on prospective and retrospective memory. However, meta-memory affected dyslexics much more than normal control group. Similarly, significant differential effects were observed for simple, difficult and mixed attentional condition among between dyslexics and normal control. Dyslexic's performance was deteriorated as compared to normal control group. The findings of the study are discussed in the light of the existing literature. PMID:25538638

  16. Retrieval experience in prospective memory: strategic monitoring and spontaneous retrieval.

    PubMed

    Meier, Beat; Zimmermann, Thomas D; Perrig, Walter J

    2006-10-01

    According to the multi-process model of prospective memory (McDaniel & Einstein, 2000), performance in a prospective memory task may be due to spontaneous retrieval processes or due to strategic monitoring. Spontaneous retrieval is typically accompanied by a pop up experience and strategic monitoring by a search experience. In this study we report two experiments with young adults in which we systematically investigated whether retrieval experience differed across experimental conditions. In Experiment 1 some prospective memory targets were preceded by associated primes. We expected that presenting primes would enhance performance by an automatic activation of the intention and hence lead to an increase in pop up experiences. In Experiment 2 half of the participants received instructions containing information about the specific context in which the prospective memory task would occur, whereas the other half of the participants received no such information. We expected that specific context instructions would enhance performance by legitimate anticipation of the prospective memory task and hence would lead to an increase in search experiences. The results confirmed these expectations. They indicate that the assessment of retrieval experience can provide valuable insights into the processes underlying prospective memory performance. They also suggest that retrieval experience can vary systematically across experimental situations as predicted by the multi-process model.

  17. Deep prospecting electromagnetic system and its application

    NASA Astrophysics Data System (ADS)

    Lin, J.; Liu, C.; Zhou, F.; Zhang, W.; Chen, J.; Xue, K.; Sun, C.; Xu, W.; Hu, R.

    2011-12-01

    Today mineral resource is becoming the impediment to the society development because less and less mineral resource can be available. People are trying all kinds of technological tools to find the mineral deposit concealed in deep lithosphere. Unfortunately, current technology can not meet the exploration requirement completely and it is still difficult to know whether a deep mineral deposit exists and how it is presented at a considered site. In order to meet the requirement of discovering the mineral deposit in the second mine prospecting space (500-2000m under earth surface), we developed a deep prospecting electromagnetic system (DPS-I). This system consists of an electromagnetic receiver array and a high-power transmitter. The receiver array consists of 24 sub-receivers and one controller and has up to 53 electromagnetic channels. The sub-receivers can be extended conveniently if the user would like and they communicate with the controller through a cable or wireless antenna. When the channel interval is set to typical value of 50 m, the system can cover 2500 m survey line at one arrangement with two magnetic records. Since the signals are collected at the same time some disturbances, such as time variable but space invariable noise, will be suppressed because they have almost the same effect to all channels. The transmitter is designed to be 45 KW of upper power limit so that strong signals will be detected. Series transmission technology is adopted to avoid unwieldiness of transmitter. In fact it is made of three portable transmission units and each one can work independently. The system can transmit several kinds of waves and records all samples of signals in time sequences. So it can work for different electromagnetic methods. The prior methods for our application are the combination of IP, CSAMT and MT. Utilizing joint inversion and model restriction, we can obtain more refined model at large depth than conventional exploration. We have applied this

  18. Planetary cores: current knowledge and future prospects

    NASA Astrophysics Data System (ADS)

    Nimmo, F.

    2011-12-01

    Observations of planetary cores tell us about the: formation; evolution; and present-day state of silicate bodies. In this review I will highlight recent results and future prospects. Formation. Core formation is detectable geochemically from siderophile element abundances and both unstable (e.g. Hf-W [1]) and stable (e.g. Cr [2], Si [3]) isotopic systems. Hf-W studies tell us that small bodies (like Vesta and perhaps Mars [4]) underwent differentiation very early, presumably due to 26Al decay [1]. Larger silicate-dominated bodies experienced stochastic addition of core material over tens of Myr, during large impacts [5]. Bodies with massive cores may result from hit-and-run collisions [6] or mantle-stripping impacts [7]. The apparent existence of a lunar core [8] places constraints on the Moon's formation. Evolution. Core solidification results in significant volume changes and surface contraction. Surface tectonics thus provides a constraint on core evolution [e.g. 9]. Dynamo generation usually depends on the rate of core cooling/solidification, which in turn depends on the mantle's ability to remove heat. Thus, an extant or ancient dynamo tells us about the long-term thermal evolution of the body [10]. In some cases, magnetic field characteristics may be related to the details of core structure and/or solidification. In others, mechanical forcing, such as tidally-driven motion [11] or impacts [12] may cause dynamo activity. Bodies with (presumed) liquid cores but no dynamo (Io, Venus) also require explanation. Present day. A body's angular momentum and tidal response depend on core properties such as CMB topography, inner core viscosity, magnetic field strength and other factors. Thus, measurements of time-varying spin state and/or gravity can be used to infer the existence of a liquid layer [13-15] and (for the Earth) core properties such as the magnetic field strength [16]. Ground-based radar observations of Mercury [14] and (in future) Europa and Io should

  19. The temporal dynamics of prospective memory: a review of the ERP and prospective memory literature.

    PubMed

    West, Robert

    2011-07-01

    This review article examines the literature using event-related brain potentials (ERPs) to study the temporal dynamics of the neurocognitive processes underpinning event-based prospective memory (PM). The successful encoding of delayed intentions is associated with slow wave activity over the frontal region in younger adults and this activity is attenuated in older adults. The realization of delayed intentions is associated with distinct components of the ERPs that are associated with the detection of a PM cue in the environment (N300), the retrieval of an intention from memory (recognition old-new effect), signaling the need to switch from the ongoing activity (frontal positivity), and configuration of the PM task set (parietal positivity). The development of prospective memory across the lifespan appears to reflect development of processes associated with retrieval of the cue-intention association from memory, and executive processes related to cue detection. The final section of the review examines the nature of executive processes that support PM within the context of a theory of the supervisory attentional system.

  20. Streptococcal diseases worldwide: present status and prospects*

    PubMed Central

    Rotta, J.; Tikhomirov, E.

    1987-01-01

    Infections caused by streptococci pathogenic for man are some of the most common bacterial diseases in temperate zones and occur very frequently in tropical and subtropical countries. The highest morbidity occurs from infections caused by group A streptococci; these infections can lead to rheumatic fever and acute glomerulonephritis. The incidence of rheumatic fever and the prevalence of rheumatic heart disease are several times higher in tropical countries than temperate countries. Recent developments in fundamental and applied research are throwing light on various aspects of the problem, e.g., the rapid (non-culture) identification of group A streptococcal infection. Analyses of the chemical structure of the M-protein molecule of group A streptococcus and of the biological properties of the epitopes of the M-protein have provided encouraging results. Furthermore, synthetic analogues of the protective immunodominant polypeptides of the M-protein have been prepared. The prospect of a streptococcal vaccine for preventing group A streptococcal diseases is thus more realistic. The control of infections caused by group B streptococci is important for the health of neonates. The identification of the chemical structure of the major group B streptococcal types may lead to development of a vaccine in the future. An alternative approach would entail the use of anti-group-B immunoglobulins, but a number of questions have to be answered before the new control measures can be introduced. The streptococci causing bacterial pneumonia, subacute bacterial endocarditis and possibly dental caries have been widely studied and promising advances have been made towards the introduction of better control of the diseases caused by these pathogens. PMID:3325183

  1. Radiovirotherapy: principles and prospects in oncology.

    PubMed

    Touchefeu, Y; Franken, P; Harrington, K J

    2012-01-01

    Radiovirotherapy is defined as the use of viruses to deliver radioisotopic treatment into infected cells. Oncolytic viruses are able to selectively target and kill cancer cells. The combination of oncolytic viruses and radiation therapies can have synergistic antitumour properties. Viruses may act as radiosensitizers, and radiations can increase viral oncolytic properties. The combination of oncolytic viruses with a virally-directed radioisotope therapy is an innovative method to combine viruses and radiation therapy, selectively within the tumour cells. The sodium/iodide symporter (NIS) is the main transgene that has been studied for this approach. NIS can mediate the uptake of isotopes of iodine and technetium 99m for in vivo gene expression imaging and therapy. This review highlights the principles of radiovirotherapy, and its recent progress. Better understanding of the regulation of NIS opens up pathways by which to potentiate the functional expression of NIS. In terms of the therapeutic isotope, Iodine-131 has been most frequently studied but other isotopes (astatine- 211, rhenium-188) are of growing interest. Oncolytic viruses are able to infect selectively and replicate in cancer cells and promising early phase clinical trials have been recently published. Their development allows a better selectivity of viral infection and adds a virus-specific cytotoxicity to the therapeutic approach. Active research into strategies such as immunosuppressive treatment and cell-based carrier systems is seeking to circumvent the host antiviral immune response and, thus, increase the potential for systemic delivery. Finally, other anticancer therapies such as chemotherapy and external beam radiotherapy may have a synergistic effect with radiovirotherapy and such combinatorial approaches offering the prospect of accelerated translation into clinical studies. PMID:22397732

  2. Supracostal percutaneous nephrolithotomy: A prospective comparative study

    PubMed Central

    Sinha, Maneesh; Krishnappa, Pramod; Subudhi, Santosh Kumar; Krishnamoorthy, Venkatesh

    2016-01-01

    Introduction: A widely prevalent fear of thoracic complications with the supracostal approach has led to its underutilization in percutaneous nephrolithotomy (PCNL). We frequently use the supracostal approach and compared the efficacy and thoracic complications of infracostal, supra 12th, and supra 11th punctures. Materials and Methods: This was a prospective study of patients who underwent PCNL between January 2005 and December 2012. The patients were divided into three groups based on the access: infracostal, supra 12th (between the 11th and 12th ribs) and supra 11th (between the 10th and 11th ribs). Clearance rates, fall in hemoglobin levels, transfusion rates, perioperative analgesic requirements, hospital stay and thoracic complications were compared. Results: Seven hundred patients were included for analysis. There were 179 (25.5%) patients in the supra 11th group, 187 (26.7%) patients in the supra 12th group and 334 (47.8%) patients in the infracostal group. The overall clearance rate was 78% with no difference in the three groups. The postoperative analgesic requirements were significantly higher in the supracostal groups and showed a graded increase from infracostal to supra 12th to supra 11th. During the study period, only 2 patients required angioembolization (0.3%) and none required open exploration. The number of patients requiring intercostal chest drain insertion was extremely low, at 1.6% and 2.2% in the supra 12th and supra 11th groups, respectively. Conclusions: Our results confirm the feasibility of the supracostal approach including punctures above the 11th rib, albeit at the cost of an increase in thoracic complications. Staying in the line of the calyx has helped us to minimize the most dreaded complication of bleeding requiring angioembolization. PMID:26941494

  3. Prospective Frontier basins off eastern Australia

    SciTech Connect

    Falvey, D.A.; Hinz, K.; Willcox, J.B.; Exon, N.F.; Symonds, P.A.; Williamson, P.E.

    1986-07-01

    Eleven thousand kilometers of high-quality multichannel seismic reflection data have been gathered in four poorly known, but prospective areas off eastern Australia. The Otway basin has an area of 100,000 km/sup 2/, more than half of which is in depths exceeding 500 m. Its Cretaceous and Cenozoic sedimentary sequence is up to 10,000 m thick and is cut by large coast-parallel normal faults. The oldest marine strata are Cenomanian. The basinal area off west Tasmania covers 40,000 km/sup 2/, two-thirds of it in offshelf depths. It contains up to 6000 m of Cretaceous and Cenozoic sequences similar to those of the Otway basin. The Lord Howe Rise is a ribbon of continent off eastern Australia, about 2000 km long and 400 km wide. Much of its crest lies in water depths of 750-1200 m. Up to 4500 m of Mesozoic and Cenozoic sequences has been identified, and extensive faulting, related to the formation of the Tasman Sea, has formed rift basins and horst and graben areas. Simple extension was apparently dominant in the south, and oblique extension in the north. The Queensland Plateau covers 200,000 km/sup 2/, half of which is in water shallower than 1000 m. The plateau behaved as a stable block during and after the Paleogene spreading episode, which formed the Coral Sea to the northeast. About 1000 m of latest Cretaceous and Cenozoic sequences are present above a planated surface on the plateau, and up to 5000 m in the flanking Queensland and Townsville Troughs to the southwest. The sequence beneath the planated surface is believed to contain Cretaceous rift-fill sediments in places.

  4. Prospects for drug therapy for hyperlipoproteinaemia.

    PubMed

    Davignon, J

    1995-04-01

    Prospects for therapy for hyperlipoproteinaemia are likely to rely more heavily on improvement of known molecules than on development of new ones aimed at various components of the plasma lipid transport system. Promising advances are revealed in both directions. A new synthetic inhibitor of HMG CoA reductase, atorvastatin, lowers plasma low-density lipoprotein (LDL)-cholesterol and triglycerides and increases high-density lipoprotein (HDL)-cholesterol with greater potency than currently available drugs of this class. A highly selective thyromimetic, CGS 26214, virtually devoid of cardiovascular effects, has potent cholesterol-lowering activity in several models, reduces post-prandial response to a fat load in rats and markedly lowers Lp(a) concentrations in monkeys. There is a trend to develop inhibitors of acyl CoA: cholesterol acyltransferase (ACAT) with more than one desirable activity. Thus, ACA-147, which inhibits cholesterol absorption, reduces LDL, prevents their oxidation and increases HDL-cholesterol, was antiatherogenic in cholesterol-fed rabbits. Sch48461 has emerged as an inhibitor of cholesterol absorption by an as yet unknown mechanism unrelated to ACAT inhibition, while a synthetic saponin, CP- 148,623, which prevents the entry of cholesterol into intestinal mucosa, has a potential for combination therapy. Approaches which may find applications in a more distant future include molecular cages to trap cholesterol selectively, "cholesterol vaccination", overexpression of the apolipoprotein E gene in the skin, and gene therapy. With improvements in understanding of the pathophysiology of dyslipoproteinaemias, drug discovery and development may focus more in future on the specific causes of disease. PMID:7621974

  5. Prospective Predictors of Patellofemoral Pain Syndrome

    PubMed Central

    Pappas, Evangelos; Wong-Tom, Wing M.

    2012-01-01

    Context: Patellofemoral pain syndrome (PFPS) is one of the most common overuse injuries. Objective: To assess the collective evidence of predisposing factors to PFPS. Data Sources: MEDLINE (1960–June 2010), EMBASE (1980–June 2010), and CINAHL (1982–June 2010). Study Selection: Studies were included if patients were asymptomatic at baseline testing (free of PFPS) and were prospectively followed for the development of the disorder. Only studies that assessed at least 1 variable that can be measured at a typical clinic were included. After duplicates were removed, 973 studies were assessed from their titles or abstracts, 20 from the full text, and from these, 7 met the inclusion criteria. Data Extraction: Data were extracted for age, weight, height, sample size, patient type (military vs civilian), follow-up periods, diagnostic methods, and diagnostic criteria. Means and standard deviations were extracted for all outcome variables. Results: Meta-analyses were performed for height, weight, leanness, Q angle, number of sit-ups, knee extension strength, and peak knee valgus angle during landing. Lower knee extension strength was the only variable that was predictive of PFPS (P < 0.01). Other variables that were identified as predictive of PFPS by single studies were vertical jump, push-ups, knee flexion and hip abduction strength, thumb-to-forearm flexibility, quadriceps and gastrocnemius flexibility, genu varum, navicular drop, knee valgus moment at initial contact during landing, social support, and palliative reaction. Conclusions: It appears that anthropometric variables are not associated with PFPS, while knee extension strength deficits appear to be predictors of PFPS. PMID:23016077

  6. Streptococcal diseases worldwide: present status and prospects.

    PubMed

    Rotta, J; Tikhomirov, E

    1987-01-01

    Infections caused by streptococci pathogenic for man are some of the most common bacterial diseases in temperate zones and occur very frequently in tropical and subtropical countries. The highest morbidity occurs from infections caused by group A streptococci; these infections can lead to rheumatic fever and acute glomerulonephritis. The incidence of rheumatic fever and the prevalence of rheumatic heart disease are several times higher in tropical countries than temperate countries.Recent developments in fundamental and applied research are throwing light on various aspects of the problem, e.g., the rapid (non-culture) identification of group A streptococcal infection. Analyses of the chemical structure of the M-protein molecule of group A streptococcus and of the biological properties of the epitopes of the M-protein have provided encouraging results. Furthermore, synthetic analogues of the protective immunodominant polypeptides of the M-protein have been prepared. The prospect of a streptococcal vaccine for preventing group A streptococcal diseases is thus more realistic.The control of infections caused by group B streptococci is important for the health of neonates. The identification of the chemical structure of the major group B streptococcal types may lead to development of a vaccine in the future. An alternative approach would entail the use of anti-group-B immunoglobulins, but a number of questions have to be answered before the new control measures can be introduced. The streptococci causing bacterial pneumonia, subacute bacterial endocarditis and possibly dental caries have been widely studied and promising advances have been made towards the introduction of better control of the diseases caused by these pathogens. PMID:3325183

  7. PROSPECT: A Computer System for Globally-Optimal Threading

    SciTech Connect

    Xu, D.; Xu, Y.

    1999-08-06

    This paper presents a new computer system, PROSPECT, for protein threading. PROSPECT employs an energy function that consists of three additive terms: (1) a singleton fitness term, (2) a distance-dependent pairwise-interaction preference term, and (3) alignment gap penalty; and currently uses FSSP as its threading template database. PROSPECT uses a divide-and-conquer algorithm to find an alignment between a query protein sequence and a protein fold template, which is guaranteed to be globally optimal for its energy function. The threading algorithm presented here significantly improves the computational efficiency of our previously-published algorithm, which makes PROSPECT a practical tool even for large protein threading problems. Mathematically, PROSPECT finds a globally-optimal threading between a query sequence of n residues and a fold template of m residues and M core secondary structures in O(nm + MnN{sup 1.5C{minus}1}) time and O(nm + nN{sup C{minus}1}) space, where C, the topological complexity of the template fold as we term, is a value which characterizes the overall structure of the considered pairwise interactions in the fold; and N represents the maximum number of possible alignments between an individual core of the fold and the query sequence when its neighboring cores are already aligned. PROSPECT allows a user to incorporate known biological constraints about the query sequence during the threading process. For given constraints, the system finds a globally-optimal threading which satisfies the constraints. Currently PROSPECT can deal with constraints which reflect geometrical relationships among residues of disulfide bonds, active sites, or determined by the NOE constraints of (low-resolution) NMR spectral data.

  8. Sleep Deprivation and Time-Based Prospective Memory

    PubMed Central

    Esposito, Maria José; Occhionero, Miranda; Cicogna, PierCarla

    2015-01-01

    Study Objectives: To evaluate the effect of sleep deprivation on time-based prospective memory performance, that is, realizing delayed intentions at an appropriate time in the future (e.g., to take a medicine in 30 minutes). Design: Between-subjects experimental design. The experimental group underwent 24 h of total sleep deprivation, and the control group had a regular sleep-wake cycle. Participants were tested at 08:00. Settings: Laboratory. Participants: Fifty healthy young adults (mean age 22 ± 2.1, 31 female). Interventions: 24 h of total sleep deprivation. Measurements and Results: Participants were monitored by wrist actigraphy for 3 days before the experimental session. The following cognitive tasks were administered: one time-based prospective memory task and 3 reasoning tasks as ongoing activity. Objective and subjective vigilance was assessed by the psychomotor vigilance task and a visual analog scale, respectively. To measure the time-based prospective memory task we assessed compliance and clock checking behavior (time monitoring). Sleep deprivation negatively affected time-based prospective memory compliance (P < 0.001), objective vigilance (mean RT: P < 0.001; slowest 10% RT: P < 0.001; lapses: P < 0.005), and subjective vigilance (P < 0.0001). Performance on reasoning tasks and time monitoring behavior did not differ between groups. Conclusions: The results highlight the potential dangerous effects of total sleep deprivation on human behavior, particularly the ability to perform an intended action after a few minutes. Sleep deprivation strongly compromises time-based prospective memory compliance but does not affect time check frequency. Sleep deprivation may impair the mechanism that allows the integration of information related to time monitoring with the prospective intention. Citation: Esposito MJ, Occhionero M, Cicogna P. Sleep deprivation and time-based prospective memory. SLEEP 2015;38(11):1823–1826. PMID:26085303

  9. Nanotechnology in agriculture: prospects and constraints.

    PubMed

    Mukhopadhyay, Siddhartha S

    2014-01-01

    Attempts to apply nanotechnology in agriculture began with the growing realization that conventional farming technologies would neither be able to increase productivity any further nor restore ecosystems damaged by existing technologies back to their pristine state; in particular because the long-term effects of farming with "miracle seeds", in conjunction with irrigation, fertilizers, and pesticides, have been questioned both at the scientific and policy levels, and must be gradually phased out. Nanotechnology in agriculture has gained momentum in the last decade with an abundance of public funding, but the pace of development is modest, even though many disciplines come under the umbrella of agriculture. This could be attributed to: a unique nature of farm production, which functions as an open system whereby energy and matter are exchanged freely; the scale of demand of input materials always being gigantic in contrast with industrial nanoproducts; an absence of control over the input nanomaterials in contrast with industrial nanoproducts (eg, the cell phone) and because their fate has to be conceived on the geosphere (pedosphere)-biosphere-hydrosphere-atmosphere continuum; the time lag of emerging technologies reaching the farmers' field, especially given that many emerging economies are unwilling to spend on innovation; and the lack of foresight resulting from agricultural education not having attracted a sufficient number of brilliant minds the world over, while personnel from kindred disciplines might lack an understanding of agricultural production systems. If these issues are taken care of, nanotechnologic intervention in farming has bright prospects for improving the efficiency of nutrient use through nanoformulations of fertilizers, breaking yield barriers through bionanotechnology, surveillance and control of pests and diseases, understanding mechanisms of host-parasite interactions at the molecular level, development of new-generation pesticides and

  10. Ocular onchocerciasis: current management and future prospects

    PubMed Central

    Babalola, Olufemi Emmanuel

    2011-01-01

    This paper reviews the current management of onchocerciasis and its future prospects. Onchocerciasis is a disease affecting millions of people in Africa, South and Central America, and Yemen. It is spread by the blackfly as a vector and caused by the filarial nematode, Onchocerca volvulus. A serious attempt was made by the Onchocerciasis Control Program between 1975 and 2002 to eliminate the vector in eleven of the endemic countries in West Africa, and with remarkable success. Formerly, the treatment was with diethyl carbamazine for the microfilaria and suramin for the adult worm. These drugs are now known to be toxic and unsuitable for mass distribution. In particular, they precipitate optic nerve disease. With the discovery of ivermectin, a much safer microfilaricide, and the decision of Merck to distribute the drug free of charge for as long as needed, the strategy of control switched to mass drug administration through community-directed treatment with ivermectin. So far, millions have received this annual or biannual treatment through the African Program for Onchocerciasis Control and the Onchocerciasis Elimination Program for the Americas. However, the problem with ivermectin is that it is a monotherapy microfilaricide which has limited effect on the adult worm, and thus will need to be continued for the life span of the adult worm, which may last up to 15 years. There are also early reports of resistance. Serious encephalopathy and death may occur when ivermectin is used in subjects heavily infested with loiasis. It seems unlikely that a break in transmission will occur with community-directed treatment with ivermectin in Africa because of population migrations and the highly efficient vector, but in the Americas some countries such as Columbia and the Oaxaca focus in Mexico have reported eradication. Vector control is only now applicable in selected situations, and particularly to control the nuisance value of the blackfly. Trials are ongoing for

  11. Nanotechnology in agriculture: prospects and constraints.

    PubMed

    Mukhopadhyay, Siddhartha S

    2014-01-01

    Attempts to apply nanotechnology in agriculture began with the growing realization that conventional farming technologies would neither be able to increase productivity any further nor restore ecosystems damaged by existing technologies back to their pristine state; in particular because the long-term effects of farming with "miracle seeds", in conjunction with irrigation, fertilizers, and pesticides, have been questioned both at the scientific and policy levels, and must be gradually phased out. Nanotechnology in agriculture has gained momentum in the last decade with an abundance of public funding, but the pace of development is modest, even though many disciplines come under the umbrella of agriculture. This could be attributed to: a unique nature of farm production, which functions as an open system whereby energy and matter are exchanged freely; the scale of demand of input materials always being gigantic in contrast with industrial nanoproducts; an absence of control over the input nanomaterials in contrast with industrial nanoproducts (eg, the cell phone) and because their fate has to be conceived on the geosphere (pedosphere)-biosphere-hydrosphere-atmosphere continuum; the time lag of emerging technologies reaching the farmers' field, especially given that many emerging economies are unwilling to spend on innovation; and the lack of foresight resulting from agricultural education not having attracted a sufficient number of brilliant minds the world over, while personnel from kindred disciplines might lack an understanding of agricultural production systems. If these issues are taken care of, nanotechnologic intervention in farming has bright prospects for improving the efficiency of nutrient use through nanoformulations of fertilizers, breaking yield barriers through bionanotechnology, surveillance and control of pests and diseases, understanding mechanisms of host-parasite interactions at the molecular level, development of new-generation pesticides and

  12. Use of particle beams for lunar prospecting

    NASA Technical Reports Server (NTRS)

    Toepfer, A. J.; Eppler, D.; Friedlander, A.; Weitz, R.

    1993-01-01

    spot irradiated by the beam is less than 1 km wide along the ground track of the satellite, resulting in the potential for high resolution. The fact that the probe could be placed in polar orbit would result in global coverage of the lunar surface. The orbital particle beam probe could provide the basis for selection of sites for more detailed prospecting by surface rovers.

  13. Nanotechnology in agriculture: prospects and constraints

    PubMed Central

    Mukhopadhyay, Siddhartha S

    2014-01-01

    Attempts to apply nanotechnology in agriculture began with the growing realization that conventional farming technologies would neither be able to increase productivity any further nor restore ecosystems damaged by existing technologies back to their pristine state; in particular because the long-term effects of farming with “miracle seeds”, in conjunction with irrigation, fertilizers, and pesticides, have been questioned both at the scientific and policy levels, and must be gradually phased out. Nanotechnology in agriculture has gained momentum in the last decade with an abundance of public funding, but the pace of development is modest, even though many disciplines come under the umbrella of agriculture. This could be attributed to: a unique nature of farm production, which functions as an open system whereby energy and matter are exchanged freely; the scale of demand of input materials always being gigantic in contrast with industrial nanoproducts; an absence of control over the input nanomaterials in contrast with industrial nanoproducts (eg, the cell phone) and because their fate has to be conceived on the geosphere (pedosphere)-biosphere-hydrosphere-atmosphere continuum; the time lag of emerging technologies reaching the farmers’ field, especially given that many emerging economies are unwilling to spend on innovation; and the lack of foresight resulting from agricultural education not having attracted a sufficient number of brilliant minds the world over, while personnel from kindred disciplines might lack an understanding of agricultural production systems. If these issues are taken care of, nanotechnologic intervention in farming has bright prospects for improving the efficiency of nutrient use through nanoformulations of fertilizers, breaking yield barriers through bionanotechnology, surveillance and control of pests and diseases, understanding mechanisms of host-parasite interactions at the molecular level, development of new-generation pesticides

  14. Prospects of the clinical utilization of melatonin.

    PubMed

    Bubenik, G A; Blask, D E; Brown, G M; Maestroni, G J; Pang, S F; Reiter, R J; Viswanathan, M; Zisapel, N

    1998-01-01

    This review summarizes the present knowledge on melatonin in several areas on physiology and discusses various prospects of its clinical utilization. Ever increasing evidence indicates that melatonin has an immuno-hematopoietic role. In animal studies, melatonin provided protection against gram-negative septic shock, prevented stress-induced immunodepression, and restored immune function after a hemorrhagic shock. In human studies, melatonin amplified the antitumoral activity of interleukin-2. Melatonin has been proven as a powerful cytostatic drug in vitro as well as in vivo. In the human clinical field, melatonin appears to be a promising agent either as a diagnostic or prognostic marker of neoplastic diseases or as a compound used either alone or in combination with the standard cancer treatment. Utilization of melatonin for treatment of rhythm disorders, such as those manifested in jet lag, shift work or blindness, is one of the oldest and the most successful clinical application of this chemical. Low doses of melatonin applied in controlled-release preparation were very effective in improving the sleep latency, increasing the sleep efficiency and rising sleep quality scores in elderly, melatonin-deficient insomniacs. In the cardiovascular system, melatonin seems to regulate the tone of cerebral arteries; melatonin receptors in vascular beds appear to participate in the regulation of body temperature. Heat loss may be the principal mechanism in the initiation of sleepiness caused by melatonin. The role of melatonin in the development of migraine headaches is at present uncertain but more research could result in new ways of treatment. Melatonin is the major messenger of light-dependent periodicity, implicated in the seasonal reproduction of animals and pubertal development in humans. Multiple receptor sites detected in brain and gonadal tissues of birds and mammals of both sexes indicate that melatonin exerts a direct effect on the vertebrate reproductive

  15. Infants' prospective control during object manipulation in an uncertain environment.

    PubMed

    Gottwald, Janna M; Gredebäck, Gustaf

    2015-08-01

    This study investigates how infants use visual and sensorimotor information to prospectively control their actions. We gave 14-month-olds two objects of different weight and observed how high they were lifted, using a Qualisys Motion Capture System. In one condition, the two objects were visually distinct (different color condition) in another they were visually identical (same color condition). Lifting amplitudes of the first movement unit were analyzed in order to assess prospective control. Results demonstrate that infants lifted a light object higher than a heavy object, especially when vision could be used to assess weight (different color condition). When being confronted with two visually identical objects of different weight (same color condition), infants showed a different lifting pattern than what could be observed in the different color condition, expressed by a significant interaction effect between object weight and color condition on lifting amplitude. These results indicate that (a) visual information about object weight can be used to prospectively control lifting actions and that (b) infants are able to prospectively control their lifting actions even without visual information about object weight. We argue that infants, in the absence of reliable visual information about object weight, heighten their dependence on non-visual information (tactile, sensorimotor memory) in order to estimate weight and pre-adjust their lifting actions in a prospective manner. PMID:25963753

  16. Spherical navigator registration using harmonic analysis for prospective motion correction.

    PubMed

    Wyatt, C L; Ari, N; Kraft, R A

    2005-01-01

    Spherical navigators are an attractive approach to motion compensation in Magnetic Resonance Imaging. Because they can be acquired quickly, spherical navigators have the potential to measure and correct for rigid motion during image acquisition (prospectively as opposed to retrospectively). A limiting factor to prospective use of navigators is the time required to estimate the motion parameters. This estimation problem can be separated into a rotational and translational component. Recovery of the rotational motion can be cast as a registration of functions defined on a sphere. Previous methods for solving this registration problem are based on optimization strategies that are iterative and require k-space interpolation. Such approaches have undesirable convergence behavior for prospective use since the estimation complexity depends on both the number of samples and the amount of rotation. We propose and demonstrate an efficient algorithm for recovery of rotational motion using spherical navigators. We decompose the navigator magnitude using the spherical harmonic transform. In this framework, rigid rotations can be recovered from an over-constrained system of equations, leading to a computationally efficient algorithm for prospective motion compensation. The resulting algorithm is compared to existing approaches in simulated and actual navigator data. These results show that the spherical harmonic based estimation algorithm is significantly faster than existing methods and so is suited for prospective motion correction.

  17. Diagnosing breast cancer using Raman spectroscopy: prospective analysis

    NASA Astrophysics Data System (ADS)

    Haka, Abigail S.; Volynskaya, Zoya; Gardecki, Joseph A.; Nazemi, Jon; Shenk, Robert; Wang, Nancy; Dasari, Ramachandra R.; Fitzmaurice, Maryann; Feld, Michael S.

    2009-09-01

    We present the first prospective test of Raman spectroscopy in diagnosing normal, benign, and malignant human breast tissues. Prospective testing of spectral diagnostic algorithms allows clinicians to accurately assess the diagnostic information contained in, and any bias of, the spectroscopic measurement. In previous work, we developed an accurate, internally validated algorithm for breast cancer diagnosis based on analysis of Raman spectra acquired from fresh-frozen in vitro tissue samples. We currently evaluate the performance of this algorithm prospectively on a large ex vivo clinical data set that closely mimics the in vivo environment. Spectroscopic data were collected from freshly excised surgical specimens, and 129 tissue sites from 21 patients were examined. Prospective application of the algorithm to the clinical data set resulted in a sensitivity of 83%, a specificity of 93%, a positive predictive value of 36%, and a negative predictive value of 99% for distinguishing cancerous from normal and benign tissues. The performance of the algorithm in different patient populations is discussed. Sources of bias in the in vitro calibration and ex vivo prospective data sets, including disease prevalence and disease spectrum, are examined and analytical methods for comparison provided.

  18. Model-based choices involve prospective neural activity

    PubMed Central

    Doll, Bradley B.; Duncan, Katherine D.; Simon, Dylan A.; Shohamy, Daphna; Daw, Nathaniel D.

    2015-01-01

    Decisions may arise via “model-free” repetition of previously reinforced actions, or by “model-based” evaluation, which is widely thought to follow from prospective anticipation of action consequences using a learned map or model. While choices and neural correlates of decision variables sometimes reflect knowledge of their consequences, it remains unclear whether this actually arises from prospective evaluation. Using functional MRI and a sequential reward-learning task in which paths contained decodable object categories, we found that humans’ model-based choices were associated with neural signatures of future paths observed at decision time, suggesting a prospective mechanism for choice. Prospection also covaried with the degree of model-based influences on neural correlates of decision variables, and was inversely related to prediction error signals thought to underlie model-free learning. These results dissociate separate mechanisms underlying model-based and model-free evaluation and support the hypothesis that model-based influences on choices and neural decision variables result from prospection. PMID:25799041

  19. A Vertical Differential Configuration in GPR prospecting

    NASA Astrophysics Data System (ADS)

    Persico, Raffaele; Pochanin, Gennadiy; Varianytsia-Roshchupkina, Liudmyla; Catapano, Ilaria; Gennarelli, Gianluca; Soldovieri, Francesco

    2015-04-01

    small objects and interfaces. This configuration can be labeled as a vertical differential configuration. At the conference, the reconstruction capabilities of this differential GPR configuration system will be discussed by means of an analysis of the problem based on a properly designed microwave tomographic inversion approach. The proposed approach exploits the Born approximation and faces the imaging as the solution of a linear inverse scattering problem. In this way, the problem of the local minima is avoided [7] and it is possible to impose some regularization to the problem in an easy way problem [8-9]. At the conference, a theoretical analysis of the mathematical propserties of the scattering operator under the vertical differential configuration will be presented showing that, with respect to the horizontal differential configuration, the vertical one allows to reject the direct coupling between the antennas but not the coupling of the antennas occurring through the air-soil interface. On the other hand, the filtering properties of the operator at hand con be considered, let say, less severe in some cases. At the conference, both some numerical and experimental results will be shown. References [1] R. Persico, F. Soldovieri, "Effects of the background removal in linear inverse scattering", IEEE Trans. Geosci. Remote Sens, vol. 46, pp. 1104-1114, April 2008. [2] L. Gurel, U. Oguz, "Three-Dimensional FDTD modeling of a ground penetrating radar", IEEE Trans. Geosci. Remote Sens, vol. 38, pp. 1513-1521, July 2000. [3] L. Gurel, U. Oguz, "Optimization of the transmitter-receiver separation in the ground penetrating radar", IEEE Trans. Antennas and Propag., vol. 51, no 3, pp. 362-370, March 2003. [4] R. Persico, F. Soldovieri, "A microwave tomography approach for a differential configuration in GPR prospecting", IEEE Trans. Antennas and Propag., vol. 54, pp. 3541 - 3548, 2006. [5] Y.A. Kopylov, S.A. Masalov, G.P. Pochanin, "The way of isolation between transmitting

  20. Prospective representation of navigational goals in the human hippocampus.

    PubMed

    Brown, Thackery I; Carr, Valerie A; LaRocque, Karen F; Favila, Serra E; Gordon, Alan M; Bowles, Ben; Bailenson, Jeremy N; Wagner, Anthony D

    2016-06-10

    Mental representation of the future is a fundamental component of goal-directed behavior. Computational and animal models highlight prospective spatial coding in the hippocampus, mediated by interactions with the prefrontal cortex, as a putative mechanism for simulating future events. Using whole-brain high-resolution functional magnetic resonance imaging and multi-voxel pattern classification, we tested whether the human hippocampus and interrelated cortical structures support prospective representation of navigational goals. Results demonstrated that hippocampal activity patterns code for future goals to which participants subsequently navigate, as well as for intervening locations along the route, consistent with trajectory-specific simulation. The strength of hippocampal goal representations covaried with goal-related coding in the prefrontal, medial temporal, and medial parietal cortex. Collectively, these data indicate that a hippocampal-cortical network supports prospective simulation of navigational events during goal-directed planning.

  1. The effect of the emotive decisions in prospect theory.

    PubMed

    Bonavia, Tomas

    2014-12-29

    The main purpose of this paper was to show that the certainty and reflection effects of prospect theory do not occur when stimuli have an affective value. To this end, 160 participants were asked to reply to a series of problems originally designed by Kahneman and Tversky (1979), but modified according to the contributions of Rottenstreich and Hsee (2001). The sample was divided into four experimental conditions, two in a gain situation and two in a loss situation. In both cases, affect-rich and affect-poor stimuli were applied in sure and probable alternatives. The findings showed that, in agreement with our hypotheses, the affective value of the stimuli altered the outcome predicted by prospect theory, showing response patterns contrary to certainty and reflection effects (p ≤ .01 and p ≤ .05 respectively). Therefore, this research supports the influence of the emotions in the decision-making process, and should be extended to other aspects of prospect theory.

  2. Motivating inhibition - reward prospect speeds up response cancellation.

    PubMed

    Boehler, Carsten N; Hopf, Jens-Max; Stoppel, Christian M; Krebs, Ruth M

    2012-12-01

    Reward prospect has been demonstrated to facilitate various cognitive and behavioral operations, particularly by enhancing the speed and vigor of processes linked to approaching reward. Studies in this domain typically employed task regimes in which participants' overt responses are facilitated by prospective rewards. In contrast, we demonstrate here that even the cancellation of a motor response can be accelerated by reward prospect, thus signifying reward-related benefits on restraint rather than approach behavior. Importantly, this facilitation occurred independent of strategy-related adjustments of response speed, which are known to systematically distort the estimation of response-cancellation speed. The fact that motivational factors can indeed facilitate response inhibition is not only relevant for understanding how motivation and response inhibition interact in healthy participants but also for work on various patient groups that display response-inhibition deficits, suggesting that core differences in the ability to inhibit motor responses have to be differentiated from motivational factors.

  3. Cost-shifting under cost reimbursement and prospective payment.

    PubMed

    Foster, R W

    1985-09-01

    Cost-shifting is seen as a three-way phenomenon involving hospital interests as well as those of government and private patients. Without economies of scale, private patients are indifferent to government policies unless underpayment leads to hospital bankruptcy. In the presence of economies of scale, private patients benefit from reductions in government payment under either cost reimbursement or prospective payment. Their interest in a shift to prospective payment depends upon the hospital's location on its cost curve. Hospitals benefit from increases in payment rates in all cases, but benefit from a shift to prospective payment only if operating in a region of declining average costs. The conventional view of cost-shifting is inconsistent with profit maximization and may be inappropriate for many voluntary hospitals as well.

  4. Prospective representation of navigational goals in the human hippocampus.

    PubMed

    Brown, Thackery I; Carr, Valerie A; LaRocque, Karen F; Favila, Serra E; Gordon, Alan M; Bowles, Ben; Bailenson, Jeremy N; Wagner, Anthony D

    2016-06-10

    Mental representation of the future is a fundamental component of goal-directed behavior. Computational and animal models highlight prospective spatial coding in the hippocampus, mediated by interactions with the prefrontal cortex, as a putative mechanism for simulating future events. Using whole-brain high-resolution functional magnetic resonance imaging and multi-voxel pattern classification, we tested whether the human hippocampus and interrelated cortical structures support prospective representation of navigational goals. Results demonstrated that hippocampal activity patterns code for future goals to which participants subsequently navigate, as well as for intervening locations along the route, consistent with trajectory-specific simulation. The strength of hippocampal goal representations covaried with goal-related coding in the prefrontal, medial temporal, and medial parietal cortex. Collectively, these data indicate that a hippocampal-cortical network supports prospective simulation of navigational events during goal-directed planning. PMID:27284194

  5. Resource depletion does not influence prospective memory in college students

    PubMed Central

    Talley Shelton, Jill; Cahill, Michael J.; Mullet, Hillary G.; Scullin, Michael K.; Einstein, Gilles O.; McDaniel, Mark A.

    2013-01-01

    This paper reports an experiment designed to investigate the potential influence of prior acts of self-control on subsequent prospective memory performance. College undergraduates (n = 146) performed either a cognitively depleting initial task (e.g., mostly incongruent Stroop task) or a less resource-consuming version of that task (e.g., all congruent Stroop task). Subsequently, participants completed a prospective memory task that required attentionally demanding monitoring processes. The results demonstrated that prior acts of self-control do not impair the ability to execute a future intention in college-aged adults. We conceptually replicated these results in three additional depletion and prospective memory experiments. This research extends a growing number of studies demonstrating the boundary conditions of the resource depletion effect in cognitive tasks. PMID:24021851

  6. Personality and substance use disorders: a prospective study.

    PubMed

    Sher, K J; Bartholow, B D; Wood, M D

    2000-10-01

    The personality systems of Cloninger (as measured by the Tridimensional Personality Questionnaire [TPQ]) and Eysenck (as measured by the Eysenck Personality Questionnaire [EPQ]) both have been linked to substance use and abuse. The current study examined the predictive utility of both systems for substance use disorder (SUD) diagnoses, both cross-sectionally and prospectively. Participants (N = 489 at baseline) completed the EPQ and TPQ and were assessed via structured diagnostic interview at baseline and 6 years later (N = 457 at follow-up). Both the EPQ and TPQ scales demonstrated bivariate cross-sectional and prospective associations with SUDs. Within each system, those dimensions marking a broad impulsive sensation-seeking or behavioral disinhibition trait were the best predictors prospectively, although the 2 systems were differentially sensitive to specific diagnoses. These relations remained significant even with autoregressivity, other concurrent SUD diagnoses, and multiple personality dimensions statistically controlled.

  7. PROSPECT: the Precision Reactor Oscillation and Spectrum Experiment

    NASA Astrophysics Data System (ADS)

    Jones, Donald; Prospect Collaboration

    2016-03-01

    PROSPECT is a phased experiment consisting of segmented Li-loaded liquid scintillator antineutrino detectors designed to probe short-baseline neutrino oscillations and precisely measure the reactor antineutrino spectrum. The experiment will be located at the High Flux Isotope Reactor (HFIR) at Oak Ridge National Lab. The first phase is a movable 3 tonne detector located 7-9 m from the compact, highly enriched uranium core. Over the past three years, PROSPECT has deployed multiple prototype detectors at HFIR to understand the local background environment and demonstrate active and passive background rejection. A two-segment prototype has been developed that demonstrates critical subsystems of the full detector. Measuring the neutrino spectrum from 235U will give insight to the recent spectral discrepancies and provide an important benchmark for future reactor experiments. As a high statistics experiment, PROSPECT will probe the sterile neutrino best-fit region within one year of operation at HFIR.

  8. On the economic prospects of nuclear fusion with tokamaks

    NASA Astrophysics Data System (ADS)

    Pfirsch, D.; Schmitter, K. H.

    1987-12-01

    A method of cost and construction energy estimation for tokamak fusion power stations conforming to the present stage of fusion development is described. The method is based on first-wall heat load constraints rather than Beta limitations, which, however, might eventually be the more critical of the two. It is used to discuss the economic efficiency of pure fusion, with particular reference to the European study entitled Environmental Impact and Economic Prospects of Nuclear Fusion (1986). It is shown that the claims made therein for the economic prospects of pure fusion with tokamaks, when discussed on the basis of the present-day technology, do not stand up to critical examination. A fusion-fission hybrid, however, could afford more positive prospects. Support for the stated method is derived when it is properly applied for cost estimation of advanced gas-cooled and Magnox reactors, the two examples presented by the European study to disprove it.

  9. Motivating inhibition - reward prospect speeds up response cancellation.

    PubMed

    Boehler, Carsten N; Hopf, Jens-Max; Stoppel, Christian M; Krebs, Ruth M

    2012-12-01

    Reward prospect has been demonstrated to facilitate various cognitive and behavioral operations, particularly by enhancing the speed and vigor of processes linked to approaching reward. Studies in this domain typically employed task regimes in which participants' overt responses are facilitated by prospective rewards. In contrast, we demonstrate here that even the cancellation of a motor response can be accelerated by reward prospect, thus signifying reward-related benefits on restraint rather than approach behavior. Importantly, this facilitation occurred independent of strategy-related adjustments of response speed, which are known to systematically distort the estimation of response-cancellation speed. The fact that motivational factors can indeed facilitate response inhibition is not only relevant for understanding how motivation and response inhibition interact in healthy participants but also for work on various patient groups that display response-inhibition deficits, suggesting that core differences in the ability to inhibit motor responses have to be differentiated from motivational factors. PMID:22921189

  10. Outgassing and contamination properties of prospective Apollo Telescope Mount materials.

    NASA Technical Reports Server (NTRS)

    Poehlmann, H. C.

    1972-01-01

    Some of the test techniques used to evaluate the outgassing and contamination characteristics of prospective Apollo telescope mount (ATM) materials are reviewed. These include a screening test providing information on weight losses of materials, weights of their condensed outgas products, and white-light scattered by the condensed products. They also include an ultraviolet-region screening test and a comprehensive continuous in situ weight-loss test. Examples are presented of data obtained from each of the tests on various prospective ATM materials.

  11. International prospects for clean coal technologies (Focus on Asia)

    SciTech Connect

    Gallaspy, D.T.

    1997-12-31

    The purpose of this paper is to propose Asia as a focus market for commercialization of CCT`s; describe the principles for successful penetration of CCT`s in the international market; and summarize prospects for CCT`s in Asia and other international markets. The paper outlines the following: Southern Company`s clean coal commitment; acquisition of Consolidated Electric Power Asia (CEPA); the prospects for CCT`s internationally; requirements for CCT`s widespread commercialization; CEPA`s application of CCT`s; and gas turbine power plants as a perfect example of a commercialization driver.

  12. International cooperation in planetary exploration - Past success and future prospects

    NASA Technical Reports Server (NTRS)

    Rosendhal, Jeffrey D.

    1987-01-01

    A review is given of the ways in which the National Aeronautics and Space Administration (NASA) has participated in international efforts to explore the solar system. Past examples of successful international cooperative programs are described. Prospects for future cooperative efforts are discussed with emphasis placed on current events, issues, and trends which are likely to affect possibilities for cooperation over the next 5 to 10 years. Key factors which will play a major role in shaping future prospects for cooperation include the move towards balancing the budget in the United States and the impact of the Challenger accident on the NASA program.

  13. Status and Prospects of the Fast Ignition Inertial Fusion Concept

    SciTech Connect

    Key, M H

    2006-11-15

    Fast ignition is an alternate concept in inertial confinement fusion, which has the potential for easier ignition and greater energy multiplication. If realized it could improve the prospects for inertial fusion energy. It poses stimulating challenges in science and technology and the research is approaching a key stage in which the feasibility of fast ignition will be determined. This review covers the concepts, the state of the science and technology, the near term prospects and the challenges and risks involved in demonstrating high gain fast ignition.

  14. [What are the different prospects for positive treatment?].

    PubMed

    Casagrande, Alice

    2010-01-01

    While the concept of positive treatment is undeniably fashionable, the manner in which it is replacing the concept of mistreatment raises questions. What is the significance of this semantic development and what should be deduced from this new term with regard to the effective development of professional practices? Three different prospects appear to await the term positive treatment: incarnating a figure of denial, acting as an asset, or infinitely more preferable, bringing about a questioning of professional practices. But this third prospect is not without its challenges: it cannot exist without managerial involvement focusing on the ethical requirements of positive treatment in terms of respect for people in care.

  15. KLOE results in flavour physics and prospects for KLOE-2

    NASA Astrophysics Data System (ADS)

    Czerwiński, E.; Babusci, D.; Badoni, D.; Balwierz, I.; Bencivenni, G.; Bini, C.; Bloise, C.; Bocci, V.; Bossi, F.; Branchini, P.; Budano, A.; Caldeira Balkeståhl, L.; Capon, G.; Ceradini, F.; Ciambrone, P.; Czerwiński, E.; Dané, E.; De Lucia, E.; De Robertis, G.; De Santis, A.; Di Domenico, A.; Di Donato, C.; Di Salvo, R.; Domenici, D.; Erriquez, O.; Fanizzi, G.; Fantini, A.; Felici, G.; Fiore, S.; Franzini, P.; Gauzzi, P.; Giardina, G.; Giovannella, S.; Gonnella, F.; Graziani, E.; Happacher, F.; Höistad, B.; Iafolla, L.; Iarocci, E.; Jacewicz, M.; Johansson, T.; Kupść, A.; Lee-Franzini, J.; Leverington, B.; Loddo, F.; Mandaglio, G.; Martemianov, M.; Martini, M.; Mascolo, M.; Messi, R.; Miscetti, S.; Morello, G.; Moricciani, D.; Moskal, P.; Nguyen, F.; Passeri, A.; Patera, V.; Prado Longhi, I.; Ranieri, A.; Redmer, C. F.; Santangelo, P.; Sarra, I.; Schioppa, M.; Sciascia, B.; Silarski, M.; Taccini, C.; Tortora, L.; Venanzoni, G.; Versaci, R.; Wiślicki, W.; Wolke, M.; Zdebik, J.

    2013-08-01

    A review of the most recent results in flavour physics obtained by the KLOE experiment at DAΦNE collider together with prospects for kaon physics at KLOE-2 is presented. A brief description of KS meson lifetime measurement and determination of upper limit for BR(Ks→3π0) are discussed. In addition a CPT symmetry test in the Standard Model Extension framework and study of the Dalitz plot of η→π+π-π0 are reported. Last two sections are devoted to the KLOE-2 project and prospects in flavour physics.

  16. A Vertical Differential Configuration in GPR prospecting

    NASA Astrophysics Data System (ADS)

    Persico, Raffaele; Pochanin, Gennadiy; Varianytsia-Roshchupkina, Liudmyla; Catapano, Ilaria; Gennarelli, Gianluca; Soldovieri, Francesco

    2015-04-01

    small objects and interfaces. This configuration can be labeled as a vertical differential configuration. At the conference, the reconstruction capabilities of this differential GPR configuration system will be discussed by means of an analysis of the problem based on a properly designed microwave tomographic inversion approach. The proposed approach exploits the Born approximation and faces the imaging as the solution of a linear inverse scattering problem. In this way, the problem of the local minima is avoided [7] and it is possible to impose some regularization to the problem in an easy way problem [8-9]. At the conference, a theoretical analysis of the mathematical propserties of the scattering operator under the vertical differential configuration will be presented showing that, with respect to the horizontal differential configuration, the vertical one allows to reject the direct coupling between the antennas but not the coupling of the antennas occurring through the air-soil interface. On the other hand, the filtering properties of the operator at hand con be considered, let say, less severe in some cases. At the conference, both some numerical and experimental results will be shown. References [1] R. Persico, F. Soldovieri, "Effects of the background removal in linear inverse scattering", IEEE Trans. Geosci. Remote Sens, vol. 46, pp. 1104-1114, April 2008. [2] L. Gurel, U. Oguz, "Three-Dimensional FDTD modeling of a ground penetrating radar", IEEE Trans. Geosci. Remote Sens, vol. 38, pp. 1513-1521, July 2000. [3] L. Gurel, U. Oguz, "Optimization of the transmitter-receiver separation in the ground penetrating radar", IEEE Trans. Antennas and Propag., vol. 51, no 3, pp. 362-370, March 2003. [4] R. Persico, F. Soldovieri, "A microwave tomography approach for a differential configuration in GPR prospecting", IEEE Trans. Antennas and Propag., vol. 54, pp. 3541 - 3548, 2006. [5] Y.A. Kopylov, S.A. Masalov, G.P. Pochanin, "The way of isolation between transmitting

  17. A Prospective Mediational Model of Sexual Aggression among College Men

    ERIC Educational Resources Information Center

    Thompson, Martie P.; Koss, Mary P.; Kingree, J. B.; Goree, Jennifer; Rice, John

    2011-01-01

    Guided by the Theory of Planned Behavior (TPB), the authors examined prospective associations of attitudes, norms, and control with sexual aggression (SA) perpetration 1 year later among male college students. Data were collected from 652 males via confidential, self-report surveys at the end of their 1st and 2nd years in college. Results…

  18. Anxiety Sensitivity as a Prospective Predictor of Alcohol Use Disorders

    ERIC Educational Resources Information Center

    Schmidt, Norman B.; Buckner, Julia D.; Keough, Meghan E.

    2007-01-01

    Emerging evidence suggests that elevated anxiety sensitivity (AS) is associated with substance use disorders. However, prospective evidence regarding this association is currently lacking. The primary aim of the present study was to determine whether AS is involved in the pathogenesis of substance-related psychopathology. A large, nonclinical…

  19. Toward Programmatic Research on Virtue Assessment: Challenges and Prospects

    ERIC Educational Resources Information Center

    Fowers, Blaine J.

    2014-01-01

    Poor construct definition has characterized research on virtue, beginning with Hartshorne and May's honesty studies and continuing to the present. Recently, scholars have begun to define virtues in ways that improve the prospects for measuring virtue constructs, but a coordinated, programmatic approach is necessary for success in virtue…

  20. Upper proterozoic geology and hydrocarbon prospects, Metropolitan Moscow District

    SciTech Connect

    Kuz`menko, Yu.T.; Kuklinskii, A.Ya.; Pimenov, Yu.G.

    1994-09-01

    New data on the geological makeup of the Teplostansk Graben of the Moscow Aulacogen deals with lithological-geochemical rock characteristics in deep drillholes in the Moscow area and about the enclosed bituminoids. Hydrocarbon prospects of the Upper Proterozoic beds in the graben have been evaluated.

  1. Evaluating Prospects: The Criteria Used to Hire New Teachers

    ERIC Educational Resources Information Center

    Cranston, Jerome

    2012-01-01

    Teacher hiring decisions have far-reaching effects. Accordingly, it is important that prospective teachers be scrutinized carefully. The process that yields new teacher hires also deserves careful analysis. This article reports on key findings derived from a larger study that examined the overall organization of the hiring process and how criteria…

  2. The Teacher Internship Experiences of Prospective High School Mathematics Teachers

    ERIC Educational Resources Information Center

    Rhoads, Kathryn; Radu, Iuliana; Weber, Keith

    2011-01-01

    Nine prospective secondary mathematics teachers were interviewed about their teaching internship experience. The results of these interviews revealed that 7 of the 9 participants professed to value reform-oriented teaching and conceptual understanding in mathematics, yet all were paired with cooperating teachers who seemed to value traditional…

  3. The Leisure Behavior of the Turkish Prospective Teachers

    ERIC Educational Resources Information Center

    Aslan, Nese; Cansever, Belgin Arslan

    2016-01-01

    This study focused on prospective teachers' leisure behaviors. For this purpose, 47 fourth grade undergraduate students in Faculty of Education in Ege University, Izmir, Turkey participated. A qualitative research design was used in the study. In the process of analysing the data, Greimas' Actant Model as one of the analysing models in Semiology…

  4. Prospective Teachers' Ideas about Teacher Recruitment and Their Professional Future

    ERIC Educational Resources Information Center

    Sahin, Idris

    2011-01-01

    This research aimed to reveal how prospective teachers viewed their professional future and to discern how their lives would be affected in case they were not recruited as teachers. The research was conducted on senior students at Buca Faculty of Education. The sample of the research consisted of 149 senior students, including 82 girls and 67…

  5. Prospective Adaptation in the Use of External Representations

    ERIC Educational Resources Information Center

    Martin, Lee; Schwartz, Daniel L.

    2009-01-01

    An important element of adaptive expertise involves stepping away from a routine to retool one's knowledge or environment. The current study investigated two forms of this adaptive pattern: fault-driven adaptations, which are reactions to a difficulty, and prospective adaptations, which are proactive reformulations. Graduate and undergraduate…

  6. Prospective Teachers as Learners: Intellectual Development and Learning To Teach.

    ERIC Educational Resources Information Center

    Holt-Reynolds, Diane

    William Perry argued that adult development can be marked by a progressively refined set of questions focused on how Authorities like teachers can support multiple right answers and still maintain that there are wrong answers. When prospective English teachers view right and wrong answers as relativistic, they seem to view themselves as…

  7. Prospective payment for hospital capital by Medicare: issues and options.

    PubMed

    Sloan, F A; Valvona, J

    1986-01-01

    After this year, Medicare will no longer reimburse capital-related expenses. Instead, a new approach may be implemented. Should the new capital payment scheme be prospective? Should Medicare continue to recognize return on equity? What will be the relationship between Medicare payment and health care planning? These and other questions should be asked since the answers will directly affect the health care setting.

  8. Development in Children with Achondroplasia: A Prospective Clinical Cohort Study

    ERIC Educational Resources Information Center

    Ireland, Penelope J.; Donaghey, Samantha; McGill, James; Zankl, Andreas; Ware, Robert S.; Pacey, Verity; Ault, Jenny; Savarirayan, Ravi; Sillence, David; Thompson, Elizabeth; Townshend, Sharron; Johnston, Leanne M.

    2012-01-01

    Aim: Achondroplasia is characterized by delays in the development of communication and motor skills. While previously reported developmental profiles exist across gross motor, fine motor, feeding, and communication skills, there has been no prospective study of development across multiple areas simultaneously. Method: This Australasian…

  9. Executive Functioning and Prospective Memory in Young Children

    ERIC Educational Resources Information Center

    Mahy, Caitlin E. V.; Moses, Louis J.

    2011-01-01

    The current study examined the role of executive functioning (EF) in children's prospective memory (PM) by assessing the effect of delay and number of intentions to-be-remembered on PM, as well as relations between PM and EF. Ninety-six 4-, 5-, and 6-year-olds completed a PM task and two executive function tasks. The PM task required children to…

  10. Conceptual Integration of Chemical Equilibrium by Prospective Physical Sciences Teachers

    ERIC Educational Resources Information Center

    Ganaras, Kostas; Dumon, Alain; Larcher, Claudine

    2008-01-01

    This article describes an empirical study concerning the mastering of the chemical equilibrium concept by prospective physical sciences teachers. The main objective was to check whether the concept of chemical equilibrium had become an integrating and unifying concept for them, that is to say an operational and functional knowledge to explain and…

  11. Variables Predicting Prospective Biology Teachers' Acceptance Perceptions Regarding Gene Technology

    ERIC Educational Resources Information Center

    Yilmaz, Mirac; Demirhan, Haydar

    2014-01-01

    The different opinions on products and applications of gene technology (GT) draw attention to the training and education activities related to GT. The purpose of this study is to review some variables predicting the acceptance perception regarding GT, and to investigate their changes at levels. The prospective teachers' subjective knowledge and…

  12. 37 CFR 11.118 - Duties to prospective client.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    .... 11.118 Section 11.118 Patents, Trademarks, and Copyrights UNITED STATES PATENT AND TRADEMARK OFFICE, DEPARTMENT OF COMMERCE REPRESENTATION OF OTHERS BEFORE THE UNITED STATES PATENT AND TRADEMARK OFFICE USPTO... relationship with respect to a matter is a prospective client. (b) Even when no...

  13. Epistemological Predictors of Prospective Biology Teachers' Nature of Science Understandings

    ERIC Educational Resources Information Center

    Köseoglu, Pinar; Köksal, Mustafa Serdar

    2015-01-01

    The purpose of this study was to investigate epistemological predictors of nature of science understandings of 281 prospective biology teachers surveyed using the Epistemological Beliefs Scale Regarding Science and the Nature of Science Scale. The findings on multiple linear regression showed that understandings about definition of science and…

  14. Students' Perception on the Prospect of Economics Education Study Program

    ERIC Educational Resources Information Center

    Meiriza, Mica Siar

    2015-01-01

    This study aims to determine the extent to which perceptions of students on the prospect of the Economics Education Program. The method used in this research is descriptive method in which the required data is obtained through questionnaire and technique of analyzing data used is percentages. Questionnaires were distributed through the Student…

  15. Stylistics in Teacher Training: Research Programs and Future Prospects

    ERIC Educational Resources Information Center

    Ventura, Ana Clara

    2016-01-01

    The aim of this research is to analyse and systematize the conceptual and empirical bases of the available literature on research approaches, objects of study, and future prospects in the field of stylistics, in order to encourage best practice in teacher training. Three research approaches are presented: the empiricist-behaviorist approach, the…

  16. Recent Data on Job Prospects of College-Educated Youth.

    ERIC Educational Resources Information Center

    Ryscavage, Paul

    1993-01-01

    Evidence reveals a slight shift on the part of young, college-educated workers toward technical, sales, and administrative occupations and toward lower paying service-producing industries. Whether this represents a permanent change in their job prospects remains to be seen. (Author)

  17. The Development of Prospective Secondary Biology Teachers PCK

    NASA Astrophysics Data System (ADS)

    Brown, Patrick; Friedrichsen, Patricia; Abell, Sandra

    2013-02-01

    In order to understand how prospective teachers develop knowledge for teaching, researchers must identify the types of knowledge that are integral to effective science teaching. This case study investigated how 4 prospective secondary biology teachers' science teaching orientations, knowledge of science learners, and knowledge of instructional sequence, developed during a post-baccalaureate teacher education program. Data sources included a lesson planning task and two interview-observation cycles during the participants' year-long internship. Over the course of a year, the participants' science teaching orientations were based primarily on their K-16 learning experiences, and were robust and highly resistant to change. The prospective teachers became more aware of student learning difficulties, and therefore, developed more elaborated knowledge of the requirements of learning. They consistently sequenced instruction in ways that gave priority to transmitting information to students. Prospective teachers' development of knowledge of student understanding of science and instructional sequence were congruent with their science teaching orientations. Implications are given for teacher education and future research.

  18. Data management for prospective research studies using SAS® software

    PubMed Central

    Kruse, Robin L; Mehr, David R

    2008-01-01

    Background Maintaining data quality and integrity is important for research studies involving prospective data collection. Data must be entered, erroneous or missing data must be identified and corrected if possible, and an audit trail created. Methods Using as an example a large prospective study, the Missouri Lower Respiratory Infection (LRI) Project, we present an approach to data management predominantly using SAS software. The Missouri LRI Project was a prospective cohort study of nursing home residents who developed an LRI. Subjects were enrolled, data collected, and follow-ups occurred for over three years. Data were collected on twenty different forms. Forms were inspected visually and sent off-site for data entry. SAS software was used to read the entered data files, check for potential errors, apply corrections to data sets, and combine batches into analytic data sets. The data management procedures are described. Results Study data collection resulted in over 20,000 completed forms. Data management was successful, resulting in clean, internally consistent data sets for analysis. The amount of time required for data management was substantially underestimated. Conclusion Data management for prospective studies should be planned well in advance of data collection. An ongoing process with data entered and checked as they become available allows timely recovery of errors and missing data. PMID:18786262

  19. Prospective Elementary Teachers' Misunderstandings in Solving Ratio and Proportion Problems

    ERIC Educational Resources Information Center

    Monteiro, Cecilia

    2003-01-01

    This study explores difficulties that prospective elementary mathematics teachers have with the concepts of ratio and proportion, mainly when they are engaged in solving problems using algorithm procedures. These difficulties can be traced back to earlier experiences when they were students of junior and high school. The reflection on these…

  20. Predicting Success among Prospective Disadvantaged Students in Natural Scientific Fields

    ERIC Educational Resources Information Center

    Maree, J. G.; Fletcher, L.; Sommerville, J.

    2011-01-01

    One hundred and fifty-nine Grade 11 prospective disadvantaged students in the natural sciences at the University of Pretoria completed the Study Orientation Questionnaire in Mathematics and the Senior Aptitude Test (Advanced). Fifty-nine male students (M age = 16.05; SD = 0.57) and 100 females (M age = 16.02; SD = 0.512) scored significantly…

  1. Video Games and Youth Violence: A Prospective Analysis in Adolescents

    ERIC Educational Resources Information Center

    Ferguson, Christopher J.

    2011-01-01

    The potential influence of violent video games on youth violence remains an issue of concern for psychologists, policymakers and the general public. Although several prospective studies of video game violence effects have been conducted, none have employed well validated measures of youth violence, nor considered video game violence effects in…

  2. Progress and Prospects in the Psychology of Moral Development

    ERIC Educational Resources Information Center

    Walker, Lawrence J.

    2004-01-01

    This commentary on the psychology of moral development provides a critical analysis of some important theoretical trends and empirical advances marking past progress and also discusses some future prospects for the field. The primary concern is that contemporary moral psychology suffers from a conceptual skew that is evidenced by a theoretical and…

  3. Excellent Prospects for Beautiful Minds: Marketing International Education

    ERIC Educational Resources Information Center

    Vuori, Johanna

    2015-01-01

    Purpose: The purpose of this paper is to examine how Finnish higher education institutions communicate market differentiation on the admissions webpages of their international business and technology programmes when attempting to appeal to prospective students and distinguish themselves from other institutions. Design/Methodology/Approach: The…

  4. PROSPECTIVE PREGNANCY STUDY DESIGNS FOR ASSESSING REPRODUCTIVE AND DEVELOPMENTAL TOXICANTS

    EPA Science Inventory

    Prospective Pregnancy Study Designs for Assessing Reproductive and Developmental Toxicants
    Germaine M. Buck,1 Courtney D. Johnson,1 Joseph Stanford,2 Anne Sweeney,3 Laura Schieve,4 John Rockett,5 Sherry G. Selevan,6 Steve Schrader 7

    Abstract
    The origin of successfu...

  5. Prospective Motion Correction using Inductively-Coupled Wireless RF Coils

    PubMed Central

    Ooi, Melvyn B.; Aksoy, Murat; Maclaren, Julian; Watkins, Ronald D.; Bammer, Roland

    2013-01-01

    Purpose A novel prospective motion correction technique for brain MRI is presented that uses miniature wireless radio-frequency (RF) coils, or “wireless markers”, for position tracking. Methods Each marker is free of traditional cable connections to the scanner. Instead, its signal is wirelessly linked to the MR receiver via inductive coupling with the head coil. Real-time tracking of rigid head motion is performed using a pair of glasses integrated with three wireless markers. A tracking pulse-sequence, combined with knowledge of the markers’ unique geometrical arrangement, is used to measure their positions. Tracking data from the glasses is then used to prospectively update the orientation and position of the image-volume so that it follows the motion of the head. Results Wireless-marker position measurements were comparable to measurements using traditional wired RF tracking coils, with the standard deviation of the difference < 0.01 mm over the range of positions measured inside the head coil. RF safety was verified with B1 maps and temperature measurements. Prospective motion correction was demonstrated in a 2D spin-echo scan while the subject performed a series of deliberate head rotations. Conclusion Prospective motion correction using wireless markers enables high quality images to be acquired even during bulk motions. Wireless markers are small, avoid RF safety risks from electrical cables, are not hampered by mechanical connections to the scanner, and require minimal setup times. These advantages may help to facilitate adoption in the clinic. PMID:23813444

  6. Labor Market Prospects for University Graduates in Nigeria.

    ERIC Educational Resources Information Center

    Dabalen, Andrew; Oni, Bankole; Adekola, Olatunde A.

    2001-01-01

    Analysis of labor statistics and employer surveys indicated that the unemployment rate for university graduates in Nigeria may be 22 percent and that their prospects for employment have worsened over time. Employers believe that graduates are poorly trained and unproductive, their skills have deteriorated over the last decade, and shortcomings are…

  7. Differentiated Instruction: Hong Kong Prospective Teachers' Teaching Efficacy and Beliefs

    ERIC Educational Resources Information Center

    Wan, Sally Wai-Yan

    2016-01-01

    Catering for learner diversity is one of the key areas in the recent educational reform in Hong Kong. Pre-service teacher education acts as a fundamental way to equip pre-service teachers ready for accommodating diverse learning needs and to build up pre-service teachers' self-efficacy. The purpose of the study is to examine prospective teachers'…

  8. Preferences for prolonging life: a prospect theory approach.

    PubMed

    Winter, Laraine; Lawton, M Powell; Ruckdeschel, Katy

    2003-01-01

    Kahneman and Tversky's (1979) Prospect theory was tested as a model of preferences for prolonging life under various hypothetical health statuses. A sample of 384 elderly people living in congregate housing (263 healthy, 131 frail) indicated how long (if at all) they would want to live under each of nine hypothetical health conditions (e.g., limited to bed or chair in a nursing home). Prospect theory, a decision model which takes into account the individual's point of reference, would predict that frail people would view prospective poorer health conditions as more tolerable and express preferences to live longer in worse health than would currently healthy people. In separate analyses of covariance, we evaluated preferences for continued life under four conditions of functional ability, four conditions of cognitive impairment, and three pain conditions--each as a function of participant's current health status (frail vs. healthy). The predicted interaction between frailty and declining prospective health status was obtained. Frail participants expressed preferences for longer life under more compromised health conditions than did healthy participants. The results imply that such preferences are malleable, changing as health deteriorates. They also help explain disparities between proxy decision-makers' and patients' own preferences as expressed in advance directives.

  9. 48 CFR 52.216-5 - Price Redetermination-Prospective.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... exceed any ceiling price included in the contract. (b) Definition. Costs, as used in this clause, means... 48 Federal Acquisition Regulations System 2 2010-10-01 2010-10-01 false Price Redetermination....216-5 Price Redetermination—Prospective. As prescribed in 16.205-4, insert the following clause:...

  10. Hard diffractive results and prospects at the Tevatron

    SciTech Connect

    Peters, Krisztian; /Manchester U.

    2006-01-01

    We review hard diffractive results and prospects at the Tevatron with an emphasis on factorization breaking in diffractive processes. Upper limits on the exclusive di-jet and {chi}{sub c}{sup 0} production cross sections at CDF and the status of the D0 Forward Proton Detectors are discussed.

  11. Academic Self-Efficacy and Prospective ELT Teachers' Achievement

    ERIC Educational Resources Information Center

    Sariçoban, Arif; Behjoo, Bahram Mohammadi

    2016-01-01

    This study aims to scrutinize the possible relationship between academic self-efficacy beliefs and foreign language achievement among prospective ELT teachers. To do so, the data for the study were collected through a questionnaire, "College Academic Self-Efficacy Scale" adapted from Owen & Froman (1988), consisting of 33 items…

  12. Mentoring Prospective Principals: Determinants of Productive Mentor-Mentee Relationship

    ERIC Educational Resources Information Center

    Schechter, Chen

    2014-01-01

    Mentoring contributes to prospective principals' growth, easing their transition from the role of teacher to that of administrator. This article reports findings from a study aimed at examining the determinant factors affecting the mentor-mentee relationship in a uniquely designed principal preparation program in New York City. The study…

  13. Reflections of Prospective Teachers Regarding Case-Based Learning

    ERIC Educational Resources Information Center

    Celik, Serkan; Demirarslan Cevik, Yasemin; Haslaman, Tulin

    2012-01-01

    The growing interest toward case-based learning for teacher education can be attributed to the inherent potential of cases in terms of providing prospective teachers with opportunities to engage in analyzing and solving realistic teaching cases and to apply what they learned in classes to solve these practical teaching issues. The objective of…

  14. Attitudes of Prospective Human Resource Personnel towards Distance Learning Degrees

    ERIC Educational Resources Information Center

    Udegbe, I. Bola

    2012-01-01

    This study investigated the attitudes of Prospective Human Resource Personnel toward degrees obtained by distance learning in comparison to those obtained through conventional degree program. Using a cross-sectional survey design, a total of 215 postgraduate students who had been or had potential to be involved in the hiring process in their…

  15. Using Mathematics Literature with Prospective Secondary Mathematics Teachers

    ERIC Educational Resources Information Center

    Jett, Christopher C.

    2014-01-01

    Literature in mathematics has been found to foster positive improvements in mathematics learning. This manuscript reports on a mathematics teacher educator's use of literature via literature circles with 11 prospective secondary mathematics teachers in a mathematics content course. Using survey and reflection data, the author found that…

  16. Prospective TESOL Teachers' Beliefs, Understandings, and Experiences of Cooperative Learning

    ERIC Educational Resources Information Center

    Wallestad, Chizuko Konishi

    2010-01-01

    The purpose of this present ethnographic case study is to explore the initial and developing beliefs, understandings, and experiences of prospective language teachers as they engage in the process of learning about cooperative learning (CL) and in putting it into practice in a TESOL graduate program in the U.S. Data collection includes multiple…

  17. Medicare Prospective Reimbursement for Mental Health Services: A Literature Review.

    ERIC Educational Resources Information Center

    Holcomb, William R.; Thompson, Warren A.

    1988-01-01

    Reviews literature evaluating appropriateness of Medicare's prospective payment system (PPS) through Diagnostic-Related Groups (DRGs), since its implementation in 1983, for psychiatric care. Cites shortcomings that make the system untenable for mental health care, including lack of homogeneity of DRGs, inability to predict length of stay, and…

  18. The Animal Experimentation Controversy: Ethical Views of Prospective Teachers

    ERIC Educational Resources Information Center

    de Villiers, Rian

    2012-01-01

    Vivisection (live animal experimentation) is a controversial issue for many people. The purpose of this case study is to examine the attitudes of prospective teachers toward vivisection in education and research, to determine if gender has an influence on these attitudes, and to discuss the implications of these attitudes with regard to teaching…

  19. Prospective and Retrospective Processing in Associative Mediated Priming

    ERIC Educational Resources Information Center

    Jones, Lara L.

    2012-01-01

    Mediated priming refers to the faster word recognition of a target (e.g., milk) following presentation of a prime (e.g., pasture) that is related indirectly via a connecting "mediator" (e.g., cow). Association strength may be an important factor in whether mediated priming occurs prospectively (with target activation prior to its presentation) or…

  20. Proof Construction and Evaluation Practices of Prospective Mathematics Educators

    ERIC Educational Resources Information Center

    Imamoglu, Yesim; Togrol, Aysenur Yontar

    2015-01-01

    This study was conducted with 93 freshmen and 82 senior prospective mathematicians and mathematics teachers in order to investigate how they construct and evaluate proofs and whether there are any significant differences in their proof construction (with respect to department and grade) and proof evaluation (with respect to department)…

  1. Prospective Nationwide Study of Aeromonas Infections in France▿

    PubMed Central

    Lamy, Brigitte; Kodjo, Angeli; Laurent, Frédéric

    2009-01-01

    We report a systematic prospective multicenter nationwide study of clinical Aeromonas infections in France. During 6 months (May to October 2006), 78 cases of aeromonosis were reviewed for risk factors and clinical, microbiological, and antimicrobial susceptibility data. They included wound infections (44%), bacteremia (26%), enteritis (19%), respiratory tract infections (6%), and miscellaneous (5%) infections. PMID:19244464

  2. Anxiety and Piano Exams: Turkish Prospective Music Teachers' Experiences

    ERIC Educational Resources Information Center

    Güven, Elif

    2016-01-01

    The purpose of this study is to determine the test anxiety levels of prospective music teachers and their opinions regarding anxiety in piano exams. Test Anxiety Inventory (TAI) and semi-structured interviews were used to meet the purpose. Interviews were conducted with students prior to and after the piano exam. As a result of the study it was…

  3. Whistle-Blowing Intentions of Prospective Teachers: Education Evidence

    ERIC Educational Resources Information Center

    Gökçe, Asiye Toker

    2013-01-01

    This study investigates whistle-blowing intentions of prospective teachers. Firstly, overall ethical awareness of the participants was examined, and then their underlying ethical reasons of whistle-blowing were investigated. Besides, impact on the intention to blow whistle to internal or external parties offering their job guarantee were searched.…

  4. Prospective Study of the Effectiveness of Coping in Pediatric Patients

    ERIC Educational Resources Information Center

    Zehnder, Daniel; Prchal, Alice; Vollrath, Margarete; Landolt, Markus A.

    2006-01-01

    Findings about the influence of coping on psychological adjustment in children with different medical conditions are inconsistent and often based on cross-sectional data. This prospective study evaluated the effect of various coping strategies on children's post-traumatic stress symptoms and behavioral problems 1 month and 1 year after an…

  5. Modeling Criterion Shifts and Target Checking in Prospective Memory Monitoring

    ERIC Educational Resources Information Center

    Horn, Sebastian S.; Bayen, Ute J.

    2015-01-01

    Event-based prospective memory (PM) involves remembering to perform intended actions after a delay. An important theoretical issue is whether and how people monitor the environment to execute an intended action when a target event occurs. Performing a PM task often increases the latencies in ongoing tasks. However, little is known about the…

  6. Prospective Primary Teachers' Beliefs about Mathematics

    ERIC Educational Resources Information Center

    Maasepp, Brooke; Bobis, Janette

    2015-01-01

    Concerns about the negative mathematical beliefs of prospective primary teachers have arisen from evidence that such beliefs detrimentally impact future teaching practices. The aim of this study was to explore factors contributing to the effectiveness of a mathematics content-focused intervention designed to nurture positive mathematical beliefs.…

  7. Mentoring and Tutoring as Preparation for Prospective Teachers.

    ERIC Educational Resources Information Center

    Fresko, Barbara

    This paper discusses the benefits of mentoring and tutoring for prospective teachers. Section 1 examines the general benefits of mentoring and tutoring for the mentors and tutors. The benefits include greater tolerance and empathy for individuals and groups in society, greater social awareness, better communication skills, greater self-confidence,…

  8. Educating Prospective Teachers of Biology: Findings, Limitations, and Recommendations.

    ERIC Educational Resources Information Center

    Hewson, Peter W.; Tabachnick, B. Robert; Zeichner, Kenneth M.; Lemberger, John

    1999-01-01

    Summarizes a complex study of a science-teacher-education program whose goal was to graduate teachers who held conceptual change conceptions of teaching science and were disposed to put hem into practice. Concludes that there are influences on prospective teachers from their content coursework that have significant implications for how they view…

  9. 75 FR 63443 - Prospective Grant of Exclusive Patent License

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-10-15

    ... National Institute of Standards and Technology Prospective Grant of Exclusive Patent License AGENCY... patent license. SUMMARY: This is a notice in accordance with 35 U.S.C. 209(c)(1) and 37 CFR 404.7(a)(1)(i... and commonwealths, to NIST's interest in the invention embodied in U.S. Patent Application No....

  10. 48 CFR 253.209-1 - Responsible prospective contractors.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... prospective contractor's system provides for timely placement of orders and for vendor follow-up and control... obtain needed facilities, equipment, materials, etc. (E) Accounting system and related internal controls... 48 Federal Acquisition Regulations System 3 2013-10-01 2013-10-01 false Responsible...

  11. 48 CFR 253.209-1 - Responsible prospective contractors.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... prospective contractor's system provides for timely placement of orders and for vendor follow-up and control... obtain needed facilities, equipment, materials, etc. (E) Accounting system and related internal controls... 48 Federal Acquisition Regulations System 3 2014-10-01 2014-10-01 false Responsible...

  12. 48 CFR 253.209-1 - Responsible prospective contractors.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... prospective contractor's system provides for timely placement of orders and for vendor follow-up and control... obtain needed facilities, equipment, materials, etc. (E) Accounting system and related internal controls... 48 Federal Acquisition Regulations System 3 2011-10-01 2011-10-01 false Responsible...

  13. Prospective Elementary Teachers Making Sense of Multidigit Multiplication: Leveraging Resources

    ERIC Educational Resources Information Center

    Whitacre, Ian; Nickerson, Susan D.

    2016-01-01

    This study examines how collective activity related to multiplication evolved over several class sessions in an elementary mathematics content course that was designed to foster prospective elementary teachers' number-sense development. We document how the class drew on as-if-shared ideas to make sense of multidigit multiplication in terms of…

  14. 77 FR 48130 - Prospective Grant of Exclusive Patent License

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-08-13

    ... From the Federal Register Online via the Government Publishing Office DEPARTMENT OF COMMERCE...: National Institute of Standards and Technology, Commerce. ACTION: Notice of prospective grant of exclusive patent license. SUMMARY: This is a notice in accordance with 35 U.S.C. 209(e) and 37 CFR...

  15. 77 FR 38771 - Prospective Grant of Exclusive Patent License

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-06-29

    ... From the Federal Register Online via the Government Publishing Office DEPARTMENT OF COMMERCE...: National Institute of Standards and Technology, Department of Commerce. ACTION: Notice of prospective grant of exclusive patent license. SUMMARY: This is a notice in accordance with 35 U.S.C. 209(e) and 37...

  16. 77 FR 38771 - Prospective Grant of Exclusive Patent License

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-06-29

    ... From the Federal Register Online via the Government Publishing Office DEPARTMENT OF COMMERCE...: National Institute of Standards and Technology, Commerce. ACTION: Notice of prospective grant of exclusive patent license. SUMMARY: This is a notice in accordance with 35 U.S.C. 209(e) and 37 CFR...

  17. Prospective Mathematics Teachers' Interactions with CAS-Based Textbook Elements

    ERIC Educational Resources Information Center

    Davis, Jon D.

    2015-01-01

    This study investigated how a group of 10 prospective secondary mathematics teachers (PST) read, evaluated, and adapted a textbook lesson involving the symbolic manipulation capabilities of computer algebra systems (CASS). PST read the entire lesson and tended to focus on the organizing question at the beginning of the student lesson and the CAS-S…

  18. Prospective Associations between Dietary Patterns and Cognitive Performance during Adolescence

    ERIC Educational Resources Information Center

    Nyaradi, Anett; Foster, Jonathan K.; Hickling, Siobhan; Li, Jianghong; Ambrosini, Gina L.; Jacques, Angela; Oddy, Wendy H.

    2014-01-01

    Background: The aim of the study was to investigate prospective associations between dietary patterns and cognitive performance during adolescence. Methods: Participants were sourced from the Western Australian Pregnancy Cohort (Raine) Study that includes 2868 children born between 1989 and 1992 in Perth, Western Australia. When the children were…

  19. Assessing the Writing Skill of Prospective English Teachers.

    ERIC Educational Resources Information Center

    Veal, Ramon; Hulme, Gale

    The basic communication skills of prospective teachers at the University of Georgia were assessed with knowledge and performance instruments. The knowledge instrument was a criterion referenced test in communicative arts (logical reasoning, library research, composition, language, communications media and careers, literature, reading, and oral…

  20. Prospective Memory in a Language-Trained Chimpanzee (Pan troglodytes)

    PubMed Central

    Beran, Michael J.; Perdue, Bonnie M.; Bramlett, Jessica L.; Menzel, Charles R.; Evans, Theodore A.

    2012-01-01

    Prospective memory involves the encoding, retention, and implementation of an intended future action. Although humans show many forms of prospective memory, less is known about the future oriented processes of nonhuman animals, or their ability to use prospective memory. In this experiment, a chimpanzee named Panzee, who had learned to associate geometric forms called lexigrams with real-world referents, was given a prospective memory test. Panzee selected between two foods the one she wanted to receive more immediately. That food was scattered in an outdoor yard where she could forage for it. Also outdoors were lexigram tokens, one of which represented the food item that remained indoors throughout a 30 minute period, and that could be obtained if Panzee brought in the token that matched that food item. After foraging for the selected food item, Panzee consistently remembered to retrieve and return the correct token when food was available indoors, whereas on control trials involving no indoor food she rarely returned a token. This indicated that Panzee encoded information relevant to the future action of token retrieval after extended delays for one type of food, even when a more immediately preferred food was available. PMID:23139433

  1. 42 CFR 412.340 - Fully prospective payment methodology.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 42 Public Health 2 2011-10-01 2011-10-01 false Fully prospective payment methodology. 412.340 Section 412.340 Public Health CENTERS FOR MEDICARE & MEDICAID SERVICES, DEPARTMENT OF HEALTH AND HUMAN... System for Inpatient Hospital Capital Costs Determination of Transition Period Payment Rates for...

  2. 42 CFR 412.340 - Fully prospective payment methodology.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 42 Public Health 2 2010-10-01 2010-10-01 false Fully prospective payment methodology. 412.340 Section 412.340 Public Health CENTERS FOR MEDICARE & MEDICAID SERVICES, DEPARTMENT OF HEALTH AND HUMAN... System for Inpatient Hospital Capital Costs Determination of Transition Period Payment Rates for...

  3. Adapting Math Instruction to Support Prospective Elementary Teachers

    ERIC Educational Resources Information Center

    LeSage, Ann

    2012-01-01

    Purpose: Elementary teachers' understanding of mathematics is a significant contributor to student success with mathematics. Consequently, teacher educators are frequently charged with the responsibility of supporting the development of prospective elementary teachers' mathematics content knowledge as they re-learn concepts in ways they are…

  4. mba.com Prospective Students Survey. 2015 Survey Report

    ERIC Educational Resources Information Center

    Schoenfeld, Gregg

    2015-01-01

    This 2015 "mba.com Prospective Students Survey Report" explores the motivations, career goals, preferred program types, financial choices, decision time lines, and intended study destinations of individuals interested in pursuing a graduate management education. Findings analyzed in the report represent responses from nearly 12,000…

  5. Assessment of Prospective Teachers' Views Regarding the Concept of Criticism

    ERIC Educational Resources Information Center

    Karakus, Neslihan

    2015-01-01

    Critical thinking is one of the skills that exist in the Turkish course curriculum and is aimed to be acquired by students. The objective of the study is to determine prospective Turkish teachers' perspectives regarding the concept of critism, which is both a mental exercise and carries an important role in the world of ideas. In order to assess…

  6. Prospective Teachers' Engagement in Educational Research

    ERIC Educational Resources Information Center

    Ogeyik, Muhlise Cosgun

    2013-01-01

    Research in education is one of the most striking issues in the field. Prospective teachers need to be motivated to do research during their education. Thus, when they become teachers, they can design research projects to search for some alternative ways for getting better results in their professional life. Therefore, in this study, it is aimed…

  7. Effects of Prospective Payment Financing on Rehabilitation Income.

    ERIC Educational Resources Information Center

    Evans, Ron L.; And Others

    1990-01-01

    This study compared 187 patients discharged from a Veterans Administration hospital rehabilitation unit with 215 discharges that occurred following implementation of a prospective payment system. There were no significant differences in demographics, self-care ability, or readmissions. Length of stay and referrals for home health care decreased,…

  8. Prospective Memory in a Language-Trained Chimpanzee (Pan troglodytes).

    PubMed

    Beran, Michael J; Perdue, Bonnie M; Bramlett, Jessica L; Menzel, Charles R; Evans, Theodore A

    2012-11-01

    Prospective memory involves the encoding, retention, and implementation of an intended future action. Although humans show many forms of prospective memory, less is known about the future oriented processes of nonhuman animals, or their ability to use prospective memory. In this experiment, a chimpanzee named Panzee, who had learned to associate geometric forms called lexigrams with real-world referents, was given a prospective memory test. Panzee selected between two foods the one she wanted to receive more immediately. That food was scattered in an outdoor yard where she could forage for it. Also outdoors were lexigram tokens, one of which represented the food item that remained indoors throughout a 30 minute period, and that could be obtained if Panzee brought in the token that matched that food item. After foraging for the selected food item, Panzee consistently remembered to retrieve and return the correct token when food was available indoors, whereas on control trials involving no indoor food she rarely returned a token. This indicated that Panzee encoded information relevant to the future action of token retrieval after extended delays for one type of food, even when a more immediately preferred food was available. PMID:23139433

  9. Waxy crude oil handling in Nigeria; Practices, problems, and prospects

    SciTech Connect

    Ajienka, J.A.; Ikoku, C.U. )

    1990-01-01

    With case studies, the practices, problems, and prospects of handling waxy crude oils in Nigeria are discussed. Using a rotational viscometer, the temperature dependence of rheological properties and thixotropy of these crudes were determined. Suggestions are given on how to improve handling practices. These suggestions include adequate screening and ranking of wax inhibitors, taking into account pour-point depression, viscosity, and yield value.

  10. Education in Asia and the Pacific. Retrospect: Prospect.

    ERIC Educational Resources Information Center

    Singh, Raja Roy

    Offered as a tribute to the growing and fruitful spirit of regional cooperation in education in Asia and the Pacific, this volume provides a retrospective and prospective view of cooperative efforts and conditions in the 28 countries of the region. Part One outlines landmark efforts accomplished through a series of UNESCO regional conferences…

  11. Social determinants of tuberculosis in Europe: a prospective ecological study.

    PubMed

    Ploubidis, George B; Palmer, Melissa J; Blackmore, Charlotte; Lim, Tek-Ang; Manissero, Davide; Sandgren, Andreas; Semenza, Jan C

    2012-10-01

    Tuberculosis (TB) is considered to be a disease of poverty, since its incidence is exacerbated by socioeconomic factors, inconsistent or partial treatment practices, and immigration from endemic countries. A prospective country level study, using a comprehensive dataset of TB incidence and prevalence taken from countries within the World Health Organization (WHO) European region, was conducted. We employed quintile regression to investigate the prospective association between baseline (measured in 2000) and a nation's wealth, level of egalitarianism, migration rate, health-related lifestyle and social capital with TB incidence and prevalence over a 10-yr period (2000-2009). We found that ∼50% of TB variation is accounted for by a nation's wealth and level of egalitarianism. We observed a negative prospective association between logged gross domestic product and TB rates, and a positive prospective association between income inequality and TB. National income levels per capita and income inequality are important predictors for TB incidence and prevalence in the WHO European region. They account for 50% of country-level variation, indicating the importance of a combined absolute and relative socioeconomic disadvantage in the development of TB. These findings also provide a tool for forecasting potential fluctuations in the level of TB epidemics in the WHO European region, with respect to socioeconomic changes.

  12. The Mathematical Content Knowledge of Prospective Teachers in Iceland

    ERIC Educational Resources Information Center

    Johannsdottir, Bjorg

    2013-01-01

    This study focused on the mathematical content knowledge of prospective teachers in Iceland. The sample was 38 students in the School of Education at the University of Iceland, both graduate and undergraduate students. All of the participants in the study completed a questionnaire survey and 10 were interviewed. The choice of ways to measure the…

  13. Prevalence of Blood Circulation Misconceptions among Prospective Elementary Teachers

    ERIC Educational Resources Information Center

    Pelaez, Nancy J.; Boyd, Denise D.; Rojas, Jacqueline B.; Hoover, Mildred A.

    2005-01-01

    Research shows that misconceptions about human blood circulation and gas exchange persist across grade levels. The purpose of this study was twofold: (1) to investigate the prevalence and persistence of blood circulation misconceptions among prospective elementary teachers; and (2) to evaluate the effectiveness of learning activities for…

  14. Deregulation of University Education in Nigeria: Problems and Prospects

    ERIC Educational Resources Information Center

    Adeogun, A. A.; Subair, S. T.; Osifila, G. I.

    2009-01-01

    This paper focuses on the deregulation of university education in Nigeria, its problems and prospects. The paper commences with the recognition given to education all over the world, especially higher education. Nigeria as a country gives much credence to higher education as the means for social and economic mobility, social transformation, and as…

  15. Prospective Elementary and Secondary School Mathematics Teachers' Statistical Reasoning

    ERIC Educational Resources Information Center

    Karatoprak, Rabia; Karagöz Akar, Gülseren; Börkan, Bengü

    2015-01-01

    This study investigated prospective elementary (PEMTs) and secondary (PSMTs) school mathematics teachers' statistical reasoning. The study began with the adaptation of the Statistical Reasoning Assessment (Garfield, 2003) test. Then, the test was administered to 82 PEMTs and 91 PSMTs in a metropolitan city of Turkey. Results showed that both…

  16. Teaching Prospective Teachers about Fractions: Historical and Pedagogical Perspectives

    ERIC Educational Resources Information Center

    Park, Jungeun; Gucler, Beste; McCrory, Raven

    2013-01-01

    Research shows that students, and sometimes teachers, have trouble with fractions, especially conceiving of fractions as numbers that extend the whole number system. This paper explores how fractions are addressed in undergraduate mathematics courses for prospective elementary teachers (PSTs). In particular, we explore how, and whether, the…

  17. Negative Affect and Smoking Lapses: A Prospective Analysis

    ERIC Educational Resources Information Center

    Shiffman, Saul; Waters, Andrew J.

    2004-01-01

    Relapse is a central problem in smoking treatment. Data collected at the time of relapse episodes indicate that stress and negative affect (NA) promote relapse, but retrospective data are potentially biased. The authors performed a prospective analysis of stress and NA prior to initial lapses in smokers (N = 215). Day-to-day changes in stress…

  18. Monkeys Exhibit Prospective Memory in a Computerized Task

    ERIC Educational Resources Information Center

    Evans, Theodore A.; Beran, Michael J.

    2012-01-01

    Prospective memory (PM) involves forming intentions, retaining those intentions, and later executing those intended responses at the appropriate time. Few studies have investigated this capacity in animals. Monkeys performed a computerized task that assessed their ability to remember to make a particular response if they observed a PM cue embedded…

  19. Personal Metaphors of Prospective Secondary Economics and Science Teachers

    ERIC Educational Resources Information Center

    Mellado, Lucia; Bermejo, Maria Luisa; Mellado, Vicente

    2012-01-01

    Using the responses to open questions, this qualitative study examines the personal metaphors expressed by prospective secondary education teachers, 46 science graduates and 41 economics graduates. The metaphors are classified into the four categories of Leavy, McSorley, and Bote: the behaviourist/transmissive, the cognitivist/constructivist, the…

  20. Prospective Teachers' Understanding of Decimals with Single Repeating Digits

    ERIC Educational Resources Information Center

    Burroughs, Elizabeth A.; Yopp, David

    2010-01-01

    This article investigates prospective elementary teachers' conceptions of the repeating decimal 0.999... Five students from a first-semester undergraduate course "Mathematics for Elementary School Teachers" were interviewed to ascertain their conceptions about the mathematical statement 0.999... = 1. All of the students indicated they do not…

  1. Emotional Maltreatment and Depression: Prospective Prediction of Depressive Episodes

    PubMed Central

    Liu, Richard T.; Alloy, Lauren B.; Abramson, Lyn Y.; Iacoviello, Brian M.; Whitehouse, Wayne G.

    2010-01-01

    Background Most research to date on the role of maltreatment experiences in depression has focused on physical and sexual maltreatment. However, several researchers have theorized that emotional maltreatment may be more strongly linked to depression. Furthermore, prospective studies in this area are lacking. The present study addressed these issues by examining whether experiences of current emotional maltreatment predicted the development of new prospective episodes of major (MD) or minor depression (MiD), and the subtype of hopelessness depression (HD) in young adults. It also assessed whether current emotional maltreatment from peers and from authority figures separately predicted the occurrence of depressive episodes. Method One hundred and sixty-five participants from the Cognitive Vulnerability to Depression Project were followed prospectively for 2.5 years. Current emotional maltreatment and new depressive episodes were assessed with life event and diagnostic interviews administered every six weeks. Results Greater overall emotional maltreatment predicted shorter time to onset of new MD, MiD, and HD episodes. Peer- and authority-perpetrated emotional maltreatment separately predicted shorter time to development of new HD episodes. Conclusions Greater emotional maltreatment in young adults prospectively predicts onset of depression, particularly HD. These findings highlight the importance of adult emotional maltreatment experiences in determining targets for prevention and treatment. PMID:19152341

  2. Gaps in knowledge and prospects for research of adjuvanted vaccines.

    PubMed

    Seder, Robert; Reed, Steven G; O'Hagan, Derek; Malyala, Padma; D'Oro, Ugo; Laera, Donatello; Abrignani, Sergio; Cerundolo, Vincenzo; Steinman, Lawrence; Bertholet, Sylvie

    2015-06-01

    A panel of researchers working in different areas of adjuvanted vaccines deliberated over the topic, "Gaps in knowledge and prospects for research of adjuvanted vaccines" at, "Enhancing Vaccine Immunity and Value" conference held in July 2014. Several vaccine challenges and applications for new adjuvant technologies were discussed.

  3. Target Context Specification Can Reduce Costs in Nonfocal Prospective Memory

    ERIC Educational Resources Information Center

    Lourenço, Joana S.; White, Katherine; Maylor, Elizabeth A.

    2013-01-01

    Performing a nonfocal prospective memory (PM) task results in a cost to ongoing task processing, but the precise nature of the monitoring processes involved remains unclear. We investigated whether target context specification (i.e., explicitly associating the PM target with a subset of ongoing stimuli) can trigger trial-by-trial changes in task…

  4. Investing in Prospective Cohorts for Etiologic Study of Occupational Exposures

    EPA Science Inventory

    Prospective cohorts have played a major role in understanding the role of diet, physical activity, medical conditions, and genes in the development of many diseases, but have not been widely used in the study of occupational exposures. Studies in agriculture are an exception. W...

  5. 7 CFR 1940.309 - Responsibilities of the prospective applicant.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 7 Agriculture 13 2014-01-01 2013-01-01 true Responsibilities of the prospective applicant. 1940.309 Section 1940.309 Agriculture Regulations of the Department of Agriculture (Continued) RURAL..., DEPARTMENT OF AGRICULTURE (CONTINUED) PROGRAM REGULATIONS (CONTINUED) GENERAL Environmental Program §...

  6. Factors Used by Accounting Students in Differentiating among Prospective Employers

    ERIC Educational Resources Information Center

    Phillips, Carl R.; Phillips, Antoinette S.

    2006-01-01

    Past research has revealed a number of determinants that employers use in making selection decisions about college students. However, few studies have examined those factors students use in differentiating among prospective employers and to date no studies have examined Accounting student preferences. Increased scrutiny of corporate accounting…

  7. 42 CFR 412.340 - Fully prospective payment methodology.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 42 Public Health 2 2012-10-01 2012-10-01 false Fully prospective payment methodology. 412.340 Section 412.340 Public Health CENTERS FOR MEDICARE & MEDICAID SERVICES, DEPARTMENT OF HEALTH AND HUMAN... System for Inpatient Hospital Capital Costs Determination of Transition Period Payment Rates for...

  8. 42 CFR 412.340 - Fully prospective payment methodology.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 42 Public Health 2 2014-10-01 2014-10-01 false Fully prospective payment methodology. 412.340 Section 412.340 Public Health CENTERS FOR MEDICARE & MEDICAID SERVICES, DEPARTMENT OF HEALTH AND HUMAN... System for Inpatient Hospital Capital Costs Determination of Transition Period Payment Rates for...

  9. 42 CFR 412.340 - Fully prospective payment methodology.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 42 Public Health 2 2013-10-01 2013-10-01 false Fully prospective payment methodology. 412.340 Section 412.340 Public Health CENTERS FOR MEDICARE & MEDICAID SERVICES, DEPARTMENT OF HEALTH AND HUMAN... System for Inpatient Hospital Capital Costs Determination of Transition Period Payment Rates for...

  10. 14 CFR 374a.8 - Prospective application of part.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 14 Aeronautics and Space 4 2010-01-01 2010-01-01 false Prospective application of part. 374a.8 Section 374a.8 Aeronautics and Space OFFICE OF THE SECRETARY, DEPARTMENT OF TRANSPORTATION (AVIATION PROCEEDINGS) SPECIAL REGULATIONS EXTENSION OF CREDIT BY AIRLINES TO FEDERAL POLITICAL CANDIDATES §...

  11. 14 CFR 374a.8 - Prospective application of part.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 14 Aeronautics and Space 4 2011-01-01 2011-01-01 false Prospective application of part. 374a.8 Section 374a.8 Aeronautics and Space OFFICE OF THE SECRETARY, DEPARTMENT OF TRANSPORTATION (AVIATION PROCEEDINGS) SPECIAL REGULATIONS EXTENSION OF CREDIT BY AIRLINES TO FEDERAL POLITICAL CANDIDATES §...

  12. 14 CFR 374a.8 - Prospective application of part.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 14 Aeronautics and Space 4 2013-01-01 2013-01-01 false Prospective application of part. 374a.8 Section 374a.8 Aeronautics and Space OFFICE OF THE SECRETARY, DEPARTMENT OF TRANSPORTATION (AVIATION PROCEEDINGS) SPECIAL REGULATIONS EXTENSION OF CREDIT BY AIRLINES TO FEDERAL POLITICAL CANDIDATES §...

  13. 14 CFR 374a.8 - Prospective application of part.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 14 Aeronautics and Space 4 2014-01-01 2014-01-01 false Prospective application of part. 374a.8 Section 374a.8 Aeronautics and Space OFFICE OF THE SECRETARY, DEPARTMENT OF TRANSPORTATION (AVIATION PROCEEDINGS) SPECIAL REGULATIONS EXTENSION OF CREDIT BY AIRLINES TO FEDERAL POLITICAL CANDIDATES §...

  14. 14 CFR 374a.8 - Prospective application of part.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 14 Aeronautics and Space 4 2012-01-01 2012-01-01 false Prospective application of part. 374a.8 Section 374a.8 Aeronautics and Space OFFICE OF THE SECRETARY, DEPARTMENT OF TRANSPORTATION (AVIATION PROCEEDINGS) SPECIAL REGULATIONS EXTENSION OF CREDIT BY AIRLINES TO FEDERAL POLITICAL CANDIDATES §...

  15. 36 CFR 5.14 - Prospecting, mining, and mineral leasing.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... mineral leasing. 5.14 Section 5.14 Parks, Forests, and Public Property NATIONAL PARK SERVICE, DEPARTMENT OF THE INTERIOR COMMERCIAL AND PRIVATE OPERATIONS § 5.14 Prospecting, mining, and mineral leasing... mineral leasing laws are prohibited in park areas except as authorized by law....

  16. 36 CFR 5.14 - Prospecting, mining, and mineral leasing.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... mineral leasing. 5.14 Section 5.14 Parks, Forests, and Public Property NATIONAL PARK SERVICE, DEPARTMENT OF THE INTERIOR COMMERCIAL AND PRIVATE OPERATIONS § 5.14 Prospecting, mining, and mineral leasing... mineral leasing laws are prohibited in park areas except as authorized by law....

  17. 36 CFR 5.14 - Prospecting, mining, and mineral leasing.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... mineral leasing. 5.14 Section 5.14 Parks, Forests, and Public Property NATIONAL PARK SERVICE, DEPARTMENT OF THE INTERIOR COMMERCIAL AND PRIVATE OPERATIONS § 5.14 Prospecting, mining, and mineral leasing... mineral leasing laws are prohibited in park areas except as authorized by law....

  18. 36 CFR 5.14 - Prospecting, mining, and mineral leasing.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... mineral leasing. 5.14 Section 5.14 Parks, Forests, and Public Property NATIONAL PARK SERVICE, DEPARTMENT OF THE INTERIOR COMMERCIAL AND PRIVATE OPERATIONS § 5.14 Prospecting, mining, and mineral leasing... mineral leasing laws are prohibited in park areas except as authorized by law....

  19. 36 CFR 5.14 - Prospecting, mining, and mineral leasing.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... mineral leasing. 5.14 Section 5.14 Parks, Forests, and Public Property NATIONAL PARK SERVICE, DEPARTMENT OF THE INTERIOR COMMERCIAL AND PRIVATE OPERATIONS § 5.14 Prospecting, mining, and mineral leasing... mineral leasing laws are prohibited in park areas except as authorized by law....

  20. Turkish Prospective English Teachers' Reflections on Teaching Practice

    ERIC Educational Resources Information Center

    Yildiz, Mine; Geçikli, Merve; Yesilyurt, Savas

    2016-01-01

    This study is an attempt to present the reflections of prospective English teachers in Turkey on teaching practice over their experiences and perceptions. A mixed-method research design was conducted through the use of a questionnaire involving a 5-Likert scale and one open-ended question. The participants were 120 senior students at ELT…

  1. Prospective Middle School Mathematics Teachers' Preconceptions of Geometric Translations

    ERIC Educational Resources Information Center

    Yanik, H. Bahadir

    2011-01-01

    This article reports an analysis of 44 prospective middle school mathematics teachers' pre-existing knowledge of rigid geometric transformations, specifically the geometric translations. The main data source for this study was the participants' responses to the tasks that were presented during semi-structured clinical interviews. The findings of…

  2. What Do Turkish Prospective Primary Teachers Promise for Inclusion?

    ERIC Educational Resources Information Center

    Kocbeker-Eid, Beyhan Nazli

    2016-01-01

    The purpose of this study was to examine Turkish prospective primary teachers' self-efficacy beliefs and readiness for their future roles and responsibilities as inclusive classroom teachers. Therefore, this study aimed to investigate how these roles and responsibilities relate to future teaching practices. In addition, this study examined…

  3. Seymour Sarason in Memorial: Prospects for Community and Social Change

    ERIC Educational Resources Information Center

    Maton, Kenneth I.

    2012-01-01

    Seymour Sarason passed away on January 10, 2010 at the age of 91. He was the author of more than 40 books, including The Culture of the School and the Problem of Change (1971), The Creation of Settings and the Future Societies (1972), and The Psychological Sense of Community: Prospects for a Community Psychology (1974). His groundbreaking ideas…

  4. Offenders with Intellectual Disability: A Prospective Comparative Study

    ERIC Educational Resources Information Center

    Barron, P.; Hassiotis, A.; Banes, J.

    2004-01-01

    Intellectually disabled offenders (IDO) are a poorly served and under-recognized group, who are likely to require long-term specialist treatments and interventions. Method This prospective study investigated the characteristics and factors that influence outcome in this group, with particular reference to therapeutic interventions. Sixty-one…

  5. Stage Sequences of Adolescent Substance Use: A Prospective Longitudinal Approach.

    ERIC Educational Resources Information Center

    Collins, Linda M; And Others

    Past research based primarily on cross-sectional data, has suggested a Guttman scale of substance use onset where marijuana use is preceded by alcohol use, and where sometimes tobacco is placed between alcohol and marijuana. Prospective longitudinal data is needed to determine whether the stages form a temporal sequence. A new statistical…

  6. Prospective Physical Education Teachers' Attitudes Toward Teaching Students with Disabilities.

    ERIC Educational Resources Information Center

    Hodge, Samuel R.

    1998-01-01

    Investigated the attitudes of prospective physical education (PE) teachers toward teaching students with disabilities, before and after matriculation in introductory adapted PE (APE) courses and with and without practicum experiences. Surveys of students from seven universities nationwide indicated that participation in APE courses, with or…

  7. Prospects for European Research and Development in Training & Education

    ERIC Educational Resources Information Center

    Whiting, John

    2008-01-01

    This paper outlines the prospects for research and development in the education and training fields offered by the European Communities. The position of the EC is explained in relation to the existing and forthcoming Framework Programmes of research and development. The 1987-91 Framework Programme has committed most of its funding to existing…

  8. Preferences for Prolonging Life: A Prospect Theory Approach

    ERIC Educational Resources Information Center

    Winter, Laraine; Lawton, M. Powell; Ruckdeschel, Katy

    2003-01-01

    Kahneman and Tversky's (1979) Prospect theory was tested as a model of preferences for prolonging life under various hypothetical health statuses. A sample of 384 elderly people living in congregate housing (263 healthy, 131 frail) indicated how long (if at all) they would want to live under each of nine hypothetical health conditions (e.g.,…

  9. 75 FR 20598 - Public Buildings Service; Prospect Island, Sacramento Delta, Solano County, CA; Transfer of Property

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-04-20

    ... From the Federal Register Online via the Government Publishing Office GENERAL SERVICES ADMINISTRATION Public Buildings Service; Prospect Island, Sacramento Delta, Solano County, CA; Transfer of... identified as Prospect Island, Sacramento Delta, Solano County, California to the State of...

  10. High-pitch coronary CT angiography with third generation dual-source CT: limits of heart rate.

    PubMed

    Gordic, Sonja; Husarik, Daniela B; Desbiolles, Lotus; Leschka, Sebastian; Frauenfelder, Thomas; Alkadhi, Hatem

    2014-08-01

    To determine the average heart rate (HR) and heart rate variability (HRV) required for diagnostic imaging of the coronary arteries in patients undergoing high-pitch CT-angiography (CTA) with third-generation dual-source CT. Fifty consecutive patients underwent CTA of the thoracic (n = 8) and thoracoabdominal (n = 42) aorta with third-generation dual-source 192-slice CT with prospective electrocardiography (ECG)-gating at a pitch of 3.2. No β-blockers were administered. Motion artifacts of coronary arteries were graded on a 4-point scale. Average HR and HRV were noted. The average HR was 66 ± 11 beats per minute (bpm) (range 45-96 bpm); the HRV was 7.3 ± 4.4 bpm (range 3-20 bpm). Interobserver agreement on grade of image quality for the 642 coronary segments evaluated by both observers was good (κ = 0.71). Diagnostic image quality was found for 608 of the 642 segments (95%) in 43 of 50 patients (86%). In 14% of the patients, image quality was nondiagnostic for at least one segment. HR (p = 0.001) was significantly higher in patients with at least one non-diagnostic segment compared to those without. There was no significant difference (p > 0.05) in HRV between patients with nondiagnostic segments and those with diagnostic images of all segments. All patients with a HR < 70 bpm had diagnostic image quality in all coronary segments. The effective radiation dose and scan time for the heart were 0.4 ± 0.1 mSv and 0.17 ± 0.02 s, respectively. Third-generation dual-source 192-slice CT allows for coronary angiography in the prospectively ECG-gated high-pitch mode with diagnostic image quality at HR up to 70 bpm. HRV is not significantly related to image quality of coronary CTA.

  11. Feasibility study to demonstrate cardiac imaging using fast kVp switching dual-energy computed tomography: phantom study

    NASA Astrophysics Data System (ADS)

    Madhav, Priti; Imai, Yasuhiro; Narayanan, Suresh; Dutta, Sandeep; Chandra, Naveen; Hsieh, Jiang

    2012-03-01

    Dual-energy computed tomography is a novel imaging tool that has the potential to reduce beam hardening artifacts and enhance material separation over conventional imaging techniques. Dual-energy acquisitions can be performed by using a fast kVp technology to switch between acquiring adjacent projections at two distinct x-ray spectra (80 and 140 kVp). These datasets can be used to further compute material density and monochromatic images for better material separation and beam hardening reduction by virtue of the projection domain process. The purpose of this study was to evaluate the feasibility of using dual-energy in cardiac imaging for myocardial perfusion detection and coronary artery lumen visualization. Data was acquired on a heart phantom, which consisted of the chambers and aorta filled with Iodine density solution (500 HU @ 120 kVp), a defect region between the aorta and chamber (40 HU @ 120 kVp), two Iodinefilled vessels (400 HU @ 120 kVp) of different diameters with high attenuation (hydroxyapatite) plaques (HAP), and with a 30-cm water equivalent body ring around the phantom. Prospective ECG-gated single-energy and prospective ECG-gated dual-energy imaging was performed. Results showed that the generated monochromatic images had minimal beam hardening artifacts which improved the accuracy and detection of the myocardial defect region. Material density images were useful in differentiating and quantifying the actual size of the plaque and coronary artery lumen. Overall, this study shows that dual-energy cardiac imaging will be a valuable tool for cardiac applications.

  12. Image Quality of Coronary Computed Tomography Angiography with 320-Row Area Detector Computed Tomography in Children with Congenital Heart Disease.

    PubMed

    Tada, Akihiro; Sato, Shuhei; Kanie, Yuichiro; Tanaka, Takashi; Inai, Ryota; Akagi, Noriaki; Morimitsu, Yusuke; Kanazawa, Susumu

    2016-03-01

    The objective of this study was to assess factors affecting image quality of 320-row computed tomography angiography (CTA) of coronary arteries in children with congenital heart disease (CHD). We retrospectively reviewed 28 children up to 3 years of age with CHD who underwent prospective electrocardiography (ECG)-gated 320-row CTA with iterative reconstruction. We assessed image quality of proximal coronary artery segments using a five-point scale. Age, body weight, average heart rate, and heart rate variability were recorded and compared between two groups: patients with good diagnostic image quality in all four coronary artery segments and patients with at least one coronary artery segment with nondiagnostic image quality. Altogether, 96 of 112 segments (85.7 %) had diagnostic-quality images. Patients with nondiagnostic segments were significantly younger (10.0 ± 11.6 months) and had lower body weight (5.9 ± 2.9 kg) (each p < 0.05) than patients with diagnostic image quality of all four segments (20.6 ± 13.8 months and 8.4 ± 2.5 kg, respectively; each p < 0.05). Differences in heart rate and heart rate variability between the two imaging groups were not significant. Receiver operating characteristic analyses for predicting patients with nondiagnostic image quality revealed an optimal body weight cutoff of ≤5.6 kg and an optimal age cutoff of ≤12.5 months. Prospective ECG-gated 320-row CTA with iterative reconstruction provided feasible image quality of coronary arteries in children with CHD. Younger age and lower body weight were factors that led to poorer image quality of coronary arteries.

  13. Geophysical cast history of south Centrahoma prospect, Coal County, Oklahoma

    SciTech Connect

    Schloeder, F.X.

    1987-08-01

    The South Centrahoma prospect is an example of the successful use of aeromagnetic data in locating basement-controlled structures in mature exploration areas. Although commercial hydrocarbons were not found, the test well did confirm a positive structure that had been undetected during 50 years of development of the adjacent Centrahoma field. In late 1983, Clyde Petroleum commissioned Borehole Exploration Corporation to acquire, process, and interpret 430 line-mi of high-resolution aeromagnetic data in Coal County, Oklahoma. From this survey, nine prospective leads were identified. The South Centrahoma prospect, due south of the Centrahoma field, is on the downthrown side of a major left-lateral strike-slip fault system that is expressed on aeromagnetic data. The adjacent Centrahoma field, in the Franks graben of Coal County, Oklahoma, has produced 3.4 million bbl of oil and 93.5 bcf of gas from six different reservoirs, ranging from the Ordovician Oil Creek through the Pennsylvanian Booch. This field is a cross-faulted anticline that is expressed as a surface structure, and for this reason probably attracted the Carter Oil Company to drill in 1937. Clyde Petroleum pursued a typical evaluation process for the prospect, including the purchasing and reprocessing of both Singlefold (100%) and modern CDP seismic data. These purchased data hinted at a prospect where the original aeromagnetic data had suggested, but were inconclusive. Two detail seismic lines were acquired. These modern data confirmed a positive high-relief structure similar to that shown on the aeromagnetic data. Closure ranged from 100 ft at the shallow Gilcrease sandstone to 250 ft at the Hunton Limestone. Clyde Petroleum drilled the Goss 1-3 in NW 1/4 NW 1/4, Sec. 1, T1N, R9E, to a depth of 8500 ft. The Goss well confirmed the structure, but found no commercial hydrocarbons.

  14. Perceived Values and Prospective Users' Acceptance of Prospective Technology: The Case of a Career ePortfolio System

    ERIC Educational Resources Information Center

    Tzeng, Jeng-Yi

    2011-01-01

    Technology-acceptance tests are traditionally conducted after users have obtained at least a certain amount of experience with a technology. Taking college students who had no real interaction with a prospective eportfolio system, this study investigated both their perceptions of the system and the perceptions' association with attitude towards…

  15. 42 CFR 412.20 - Hospital services subject to the prospective payment systems.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 42 Public Health 2 2010-10-01 2010-10-01 false Hospital services subject to the prospective... OF HEALTH AND HUMAN SERVICES MEDICARE PROGRAM PROSPECTIVE PAYMENT SYSTEMS FOR INPATIENT HOSPITAL SERVICES Hospital Services Subject to and Excluded From the Prospective Payment Systems for...

  16. The Views of Prospective Class Teachers about Peer Assessment in Teaching Practice

    ERIC Educational Resources Information Center

    Koc, Canan

    2011-01-01

    The present study was conducted in order to determine the opinions of prospective teachers about peer assessment in teaching practice. Twenty two prospective teachers in the 4th year of the Primary School Class Teaching Program at Cumhuriyet University participated in the study. In every teaching practice, prospective teachers observed their peers…

  17. 42 CFR 413.308 - Rules governing election of prospectively determined payment rates.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... prospectively determined payment rates. (a) Requirements. An SNF must notify its contractor at least 30 calendar... reporting period for which an SNF seeks prospectively determined payment. A newly participating SNF with no... participate in Medicare. (b) Contractor notice. After evaluating an SNF's request for prospectively...

  18. Prospective Mathematics Teachers' Difficulties in Doing Proofs and Causes of Their Struggle with Proofs

    ERIC Educational Resources Information Center

    Doruk, Muhammet; Kaplan, Abdullah

    2015-01-01

    This research aims to expose prospective mathematics teachers' difficulties while proving, as well as the reasons behind such difficulties. The research includes 121 second year undergraduate prospective teachers studying at the primary mathematics teaching department of a state university in Turkey. The study has found that prospective teachers…

  19. 42 CFR 412.304 - Implementation of the capital prospective payment system.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 42 Public Health 2 2010-10-01 2010-10-01 false Implementation of the capital prospective payment... HEALTH AND HUMAN SERVICES MEDICARE PROGRAM PROSPECTIVE PAYMENT SYSTEMS FOR INPATIENT HOSPITAL SERVICES Prospective Payment System for Inpatient Hospital Capital Costs General Provisions § 412.304 Implementation...

  20. 42 CFR 412.304 - Implementation of the capital prospective payment system.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 42 Public Health 2 2011-10-01 2011-10-01 false Implementation of the capital prospective payment... HEALTH AND HUMAN SERVICES MEDICARE PROGRAM PROSPECTIVE PAYMENT SYSTEMS FOR INPATIENT HOSPITAL SERVICES Prospective Payment System for Inpatient Hospital Capital Costs General Provisions § 412.304 Implementation...

  1. The Relationship between Learning Approaches of Prospective Teachers and Their Academic Achievement

    ERIC Educational Resources Information Center

    Gurlen, Eda; Turan, Sevgi; Senemoglu, Nuray

    2013-01-01

    To prepare for future professional challenges, prospective teachers should acquire the capabilities for independent learning. Prospective teachers should know how to learn effectively. In this article, prospective teachers' learning approaches, learning preference and the relationship between learning preference, learning approaches with…

  2. The Relationship between the Individual Values and Critical Thinking Skills of Prospective Social Sciences Teachers

    ERIC Educational Resources Information Center

    Nalcaci, Ahmet

    2012-01-01

    The aim of this study is to determine the relationship between the individual values and critical thinking skills of prospective social sciences teachers. The sample of the research is composed of a total of 298 prospective teachers, who are first-year, second-year, third-year and fourth-year students. These prospective teachers were randomly…

  3. 42 CFR 412.525 - Adjustments to the Federal prospective payment.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... HUMAN SERVICES MEDICARE PROGRAM PROSPECTIVE PAYMENT SYSTEMS FOR INPATIENT HOSPITAL SERVICES Prospective Payment System for Long-Term Care Hospitals § 412.525 Adjustments to the Federal prospective payment. (a) Adjustments for high-cost outliers. (1) CMS provides for an additional payment to a long-term care hospital...

  4. 42 CFR 412.304 - Implementation of the capital prospective payment system.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 42 Public Health 2 2013-10-01 2013-10-01 false Implementation of the capital prospective payment... HEALTH AND HUMAN SERVICES MEDICARE PROGRAM PROSPECTIVE PAYMENT SYSTEMS FOR INPATIENT HOSPITAL SERVICES Prospective Payment System for Inpatient Hospital Capital Costs General Provisions § 412.304 Implementation...

  5. 42 CFR 412.304 - Implementation of the capital prospective payment system.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 42 Public Health 2 2014-10-01 2014-10-01 false Implementation of the capital prospective payment... HEALTH AND HUMAN SERVICES MEDICARE PROGRAM PROSPECTIVE PAYMENT SYSTEMS FOR INPATIENT HOSPITAL SERVICES Prospective Payment System for Inpatient Hospital Capital Costs General Provisions § 412.304 Implementation...

  6. 42 CFR 412.304 - Implementation of the capital prospective payment system.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 42 Public Health 2 2012-10-01 2012-10-01 false Implementation of the capital prospective payment... HEALTH AND HUMAN SERVICES MEDICARE PROGRAM PROSPECTIVE PAYMENT SYSTEMS FOR INPATIENT HOSPITAL SERVICES Prospective Payment System for Inpatient Hospital Capital Costs General Provisions § 412.304 Implementation...

  7. Prospect evaluation as a function of numeracy and probability denominator.

    PubMed

    Millroth, Philip; Juslin, Peter

    2015-05-01

    This study examines how numeracy and probability denominator (a direct-ratio probability, a relative frequency with denominator 100, a relative frequency with denominator 10,000) affect the evaluation of prospects in an expected-value based pricing task. We expected that numeracy would affect the results due to differences in the linearity of number perception and the susceptibility to denominator neglect with different probability formats. An analysis with functional measurement verified that participants integrated value and probability into an expected value. However, a significant interaction between numeracy and probability format and subsequent analyses of the parameters of cumulative prospect theory showed that the manipulation of probability denominator changed participants' psychophysical response to probability and value. Standard methods in decision research may thus confound people's genuine risk attitude with their numerical capacities and the probability format used.

  8. Prospects for a civil/military transport aircraft

    NASA Technical Reports Server (NTRS)

    Jobe, C. E.; Noggle, L. W.; Whitehead, A. H., Jr.

    1978-01-01

    The similarities and disparities between commercial and military payloads, design features, missions, and transport aircraft are enumerated. Two matrices of civil/military transport aircraft designs were evaluated to determine the most cost effective payloads for a projected commercial route structure and air freight market. The probability of this market developing and the prospects for alternate route structures and freight markets are evaluated along with the possible impact on the aircraft designs. Proposals to stimulate the market and increase the viability of the common aircraft concept are reviewed and the possible impact of higher cargo demand on prospects for common civil/military freighters is postulated. The implications of planned advanced technology developments on the aircraft performance and cost are also considered.

  9. Choosy Cannibals Preferentially Consume Siblings with Relatively Low Fitness Prospects.

    PubMed

    Dugas, Matthew B; McCormack, Larkin; Gadau, Alice; Martin, Ryan A

    2016-07-01

    When an individual can selfishly cannibalize a relative or altruistically set it free, the benefits of altruism will be positively associated with the relative's fitness prospects (the benefits it receives from altruism). We tested the prediction that altruism should be preferentially directed toward high-quality relatives using larvae of the New Mexican spadefoot toad (Spea multiplicata), a species in which tadpoles plastically express omnivore and carnivore ecomorphs. In a no-choice design, we presented carnivores with sibling or nonsibling omnivores varying in developmental stage, which is positively associated with survival in this toad's ephemeral larval environment. There was a significant interaction between relatedness and developmental stage on the probability of cannibalism: carnivores were overall more likely to cannibalize less developed omnivores, but this effect was exaggerated when the potential victim was a sibling. This evidence that altruists favor relatives with high fitness prospects highlights the numerous factors shaping altruism's payoffs. PMID:27322127

  10. Choosy Cannibals Preferentially Consume Siblings with Relatively Low Fitness Prospects.

    PubMed

    Dugas, Matthew B; McCormack, Larkin; Gadau, Alice; Martin, Ryan A

    2016-07-01

    When an individual can selfishly cannibalize a relative or altruistically set it free, the benefits of altruism will be positively associated with the relative's fitness prospects (the benefits it receives from altruism). We tested the prediction that altruism should be preferentially directed toward high-quality relatives using larvae of the New Mexican spadefoot toad (Spea multiplicata), a species in which tadpoles plastically express omnivore and carnivore ecomorphs. In a no-choice design, we presented carnivores with sibling or nonsibling omnivores varying in developmental stage, which is positively associated with survival in this toad's ephemeral larval environment. There was a significant interaction between relatedness and developmental stage on the probability of cannibalism: carnivores were overall more likely to cannibalize less developed omnivores, but this effect was exaggerated when the potential victim was a sibling. This evidence that altruists favor relatives with high fitness prospects highlights the numerous factors shaping altruism's payoffs.

  11. Video games and youth violence: a prospective analysis in adolescents.

    PubMed

    Ferguson, Christopher J

    2011-04-01

    The potential influence of violent video games on youth violence remains an issue of concern for psychologists, policymakers and the general public. Although several prospective studies of video game violence effects have been conducted, none have employed well validated measures of youth violence, nor considered video game violence effects in context with other influences on youth violence such as family environment, peer delinquency, and depressive symptoms. The current study builds upon previous research in a sample of 302 (52.3% female) mostly Hispanic youth. Results indicated that current levels of depressive symptoms were a strong predictor of serious aggression and violence across most outcome measures. Depressive symptoms also interacted with antisocial traits so that antisocial individuals with depressive symptoms were most inclined toward youth violence. Neither video game violence exposure, nor television violence exposure, were prospective predictors of serious acts of youth aggression or violence. These results are put into the context of criminological data on serious acts of violence among youth.

  12. Prospect evaluation as a function of numeracy and probability denominator.

    PubMed

    Millroth, Philip; Juslin, Peter

    2015-05-01

    This study examines how numeracy and probability denominator (a direct-ratio probability, a relative frequency with denominator 100, a relative frequency with denominator 10,000) affect the evaluation of prospects in an expected-value based pricing task. We expected that numeracy would affect the results due to differences in the linearity of number perception and the susceptibility to denominator neglect with different probability formats. An analysis with functional measurement verified that participants integrated value and probability into an expected value. However, a significant interaction between numeracy and probability format and subsequent analyses of the parameters of cumulative prospect theory showed that the manipulation of probability denominator changed participants' psychophysical response to probability and value. Standard methods in decision research may thus confound people's genuine risk attitude with their numerical capacities and the probability format used. PMID:25704578

  13. Technical analysis of prospective photovoltaic systems in Utah.

    SciTech Connect

    Quiroz, Jimmy Edward; Cameron, Christopher P.

    2012-02-01

    This report explores the technical feasibility of prospective utility-scale photovoltaic system (PV) deployments in Utah. Sandia National Laboratories worked with Rocky Mountain Power (RMP), a division of PacifiCorp operating in Utah, to evaluate prospective 2-megawatt (MW) PV plants in different locations with respect to energy production and possible impact on the RMP system and customers. The study focused on 2-MW{sub AC} nameplate PV systems of different PV technologies and different tracking configurations. Technical feasibility was evaluated at three different potential locations in the RMP distribution system. An advanced distribution simulation tool was used to conduct detailed time-series analysis on each feeder and provide results on the impacts on voltage, demand, voltage regulation equipment operations, and flicker. Annual energy performance was estimated.

  14. A decade of neural networks: Practical applications and prospects

    NASA Technical Reports Server (NTRS)

    Kemeny, Sabrina (Editor); Thakoor, Anil (Editor)

    1994-01-01

    On May 11-13, 1994, JPL's Center for Space Microelectronics Technology (CSMT) hosted a neural network workshop entitled, 'A Decade of Neural Networks: Practical Applications and Prospects,' sponsored by DOD and NASA. The past ten years of renewed activity in neural network research has brought the technology to a crossroads regarding the overall scope of its future practical applicability. The purpose of the workshop was to bring together the sponsoring agencies, active researchers, and the user community to formulate a vision for the next decade of neural network research and development prospects, with emphasis on practical applications. Of the 93 participants, roughly 15% were from government agencies, 30% were from industry, 20% were from universities, and 35% were from Federally Funded Research and Development Centers (FFRDC's).

  15. Functional Status and Health Information in Canada: Proposals and Prospects

    PubMed Central

    Bickenbach, Jerome E.

    2003-01-01

    The primary obstacle to evidence-based health care quality assessment in Canada is reliable data on health encounters and episodes of care. The recent Federal/Provincial Health Accord will enhance health data collection, including standardized functional status information (FSI) for administrative records. Canadian health policy developers also agree that FSI is needed to bridge data gaps since alterations in functional status create the continuity that links all episodes of care and health service utilization. Given Canada's universal, single-payer, health financing structure, the prospects for coherent and systemwide data collection are good. This article describes the Canadian health care from the perspective of health information, and surveys proposals in electronic health technology development, the obstacles that need to be faced, and the prospects of doing so. PMID:12894637

  16. B-physics prospects with the LHCb experiment

    SciTech Connect

    Harnew, N.

    2008-04-15

    This paper summarizes the B-physics prospects of the LHCb experiment. Firstly, a brief introduction to the CKM matrix and the mechanism of CP violation in the Standard Model is given. The advantages of the LHCb experiment for B-physics exploitation will then be described, together with a short description of the detector components. Finally, the LHCb physics aims and prospects will be summarized, focusing on the measurements of sin(2{beta}) in tree and gluonic penguin diagrams, sin(2{alpha}) in B{sub d}{sup 0} {sup {yields}} {pi}{sup +}{pi}{sup -} and {pi}{sup +}{pi}{sup -}{pi}{sup 0}, neutral B-meson oscillations and the B{sub s}{sup 0} mixing phase, and the measurement of {gamma} using a variety of complementary methods.

  17. Prospective multiaxial motion correction for fMRI.

    PubMed

    Ward, H A; Riederer, S J; Grimm, R C; Ehman, R L; Felmlee, J P; Jack, C R

    2000-03-01

    Corruption of the image time series due to interimage head motion limits the clinical utility of functional MRI. This paper presents a method for real-time prospective correction of rotation and translation in all six degrees of rigid body motion. By incorporating an orbital navigator (ONAV) echo for each of the sagittal, axial, and coronal planes into the fMRI pulse sequence, rotation and translation can be measured and the spatial orientation of the image acquisition sequence that follows can be corrected prospectively in as little as 160 msec. Testing of the method using a computerized motion phantom capable of performing complex multiaxial motion showed subdegree rotational and submillimeter translational accuracy over a range of +/-8 degrees and +/-8 mm of motion. In vivo images demonstrate correction of simultaneous through-plane and in-plane motion and improved detection of fMRI activation in the presence of head motion.

  18. Toward an understanding of anticipatory pleasure deficits in schizophrenia: Memory, prospection, and emotion experience.

    PubMed

    Painter, Janelle M; Kring, Ann M

    2016-04-01

    Anticipatory pleasure deficits have been observed in people with schizophrenia. Less is known about the extent to which interrelated processes that comprise anticipatory pleasure, including memory, prospection, and emotion experience are disrupted. We asked people with (n = 32) and without (n = 29) schizophrenia or schizoaffective disorder to provide memory and prospection narratives in response to specific cues. Half of the prospections followed a memory task, and half followed a control task. People with schizophrenia generated memories similar in content and experience as controls even as they described them less clearly. However, people with schizophrenia were less likely to explicitly reference the past in their prospections, and their prospections were less detailed and richly experienced than controls, regardless of the task completed before prospection. People with schizophrenia reported similar levels of positive emotion (current and predicted) in positive prospections that followed the memory task, but less positive emotion than controls in positive prospections that followed the control task. Taken together, these results suggest that people with schizophrenia experience difficulties drawing from past experiences and generating detailed prospections. However, asking people with schizophrenia to recall and describe memories prior to prospection may increase the likelihood of drawing from the past in prospections, and may help boost current and predicted pleasure.

  19. Prospects for improvement of mining machines' cutting picks

    NASA Astrophysics Data System (ADS)

    Prokopenko, S.; Kurzina, I.; Lesin, Yu

    2016-04-01

    Advantages and disadvantages of tangential rotary picks widely used in mining machines are described. A prospective line of picks design improvement has been found based on a change in the principle of destruction. A new design of blade-type cutting picks with a reinforcing tip is proposed having extended service life, requiring less energy for rock breaking, reducing yield of fine dust and increasing the grade of the mined coal.

  20. The practical and ethical defects of surgical randomised prospective trials.

    PubMed Central

    Byer, A

    1983-01-01

    This paper presents a strong criticism of the current enthusiasm for clinical randomised prospective studies in surgery. In the process, the author probes the 'intellectualism' or lack thereof in present day surgical attitudes. The subjects are examined against a framework of ethics and inescapable dilemmas. Ways of correcting the more obvious weaknesses are suggested. The manuscript is, and is meant to be, provocative and is particularly aimed at the academic audience served by this journal. PMID:6876104