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Sample records for dimeglumine gd-bopta enhanced

  1. Gadoxetic Acid (Gd-EOB-DTPA)-Enhanced MRI versus Gadobenate Dimeglumine (Gd-BOPTA)-Enhanced MRI for Preoperatively Detecting Hepatocellular Carcinoma: an Initial Experience

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    Park, Yu Lri; Kim, Seong Hyun; Kim, Seung Hoon; Choi, Dong Il; Lee, Won Jae; Kim, Hee Jung; Koo, Ji Hyun; Lim, Hyo Keun [Samsung Medical Center, Seoul (Korea, Republic of); Jeon, Yong Hwan [Kangwon National University Hospital, Chuncheon (Korea, Republic of); Lee, Jong Mee; Kim, Min Ju [Korea University College of Medicine, Korea University Guro Hospital, Seoul (Korea, Republic of)

    2010-08-15

    This study was designed to compare the diagnostic performance of gadoxetic acid-enhanced magnetic resonance imaging (MRI) with gadobenate dimeglumine-enhanced MRI for preoperatively detecting hepatocellular carcinoma (HCC). Eighteen consecutive patients (17 men and one woman, age range: 31-73 years) with 22 HCCs underwent examinations with gadoxetic acid enhanced MRI and gadobenate dimeglumine-enhanced MRI on a 3.0-Tesla unit. The diagnosis of HCC was established after surgical resection and pathological conformation. Three observers independently reviewed each MR image in a random order on a tumor-by-tumor basis. The diagnostic accuracy of these techniques for the detection of HCC was assessed by performing an alternative free-response receiver operating characteristic (ROC) analysis. The sensitivity and positive predictive values were evaluated. The average value of the area under the ROC curve (Az) for gadoxetic acid enhanced MRI (0.887) was not significantly different from the Az (0.899) for gadobenate dimeglumine-enhanced MRI (p > 0.05). The overall sensitivities of gadoxetic acid enhanced MRI and gadobenate dimeglumine-enhanced MRI were 80% and 83%, respectively, with no significant difference (p > 0.05). The differences of the positive predictive values for the two contrast agents for each observer were not statistically significant (p > 0.05). The diagnostic performance of gadoxetic acid-enhanced MRI and gadobenate dimeglumine-enhanced MRI for preoperatively detecting HCC is quite similar

  2. Gd-BOPTA-enhanced excretory MR urography without administration of diuretics; Gd-BOPTA-gestuetzte MR-Ausscheidungsurographie ohne Diuretikagabe

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    Allkemper, T.; Tombach, B.; Heindel, W. [Muenster Univ. (Germany). Inst. fuer Klinische Radiologie

    2001-02-01

    Purpose: To evaluate the feasibility and clinical utility of Gd-BOPTA enhanced excretory magnetic resonance urography without additional administration of diuretics in correlation with conventional urography. Method: 15 preoperative patients with pelvic tumors were examined at 1.5 T using a breath-hold high-resolution 3D-FLASH sequence during first-pass as well as 5, 10, 15 minutes after iv. injection of 0.05 mmol/kg BW Gd-BOPTA (MultiHance {sup trademark}) without administration of diuretics. Post-processed coronal and multiplanar MIP reconstructions were compared to conventional excretory urography with regard to morphologic accuracy, anatomic variability, filling defects, cause and level of obstruction or compression, tumor visibility, and time-effectiveness by two independent radiologists. Results: Visualization of the urinary tract by MRU was comparable to conventional excretory urography in 14 of 15 cases. Caliceal fornices were better delineated on conventional urographies, whereas MRU was considered superior in the assessment of the inferior ureter sections, the urinary bladder and obstructive tumors, whose extents could be clearly marked out. Examination times of both techniques were comparable. Conclusion: These first results show that non-diuretic Gd-BOPTA enhanced MRU is comparable to conventional excretory urography for the preoperative diagnosis of pelvic tumors. Further improvements of this technique seem possible by optimization of examination intervals and injection doses. (orig.) [German] Ziel: Abschaetzung der Durchfuehrbarkeit und des klinischen Nutzens der Gd-BOPTA-gestuetzten MR-Ausscheidungsurographie (MRU) ohne zusaetzliche Diuretikagabe im Vergleich zur konventionellen Ausscheidungsurographie. Methoden: 15 Patienten mit Beckentumoren wurden praeoperativ an einem 1.5 T-Ganzkoerpersystem mit Hilfe einer atemgehaltenen, hochaufloesenden 3D-FLASH-Sequenz unmittelbar nach intra-venoeser Applikation von 0,05 mmol/kg KG Gd-BOPTA (MultiHance {sup

  3. Comparison of acquisition time and dose for late gadolinium enhancement imaging at 3.0 T in patients with chronic myocardial infarction using Gd-BOPTA

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    Doltra, A.; Skorin, A.; Gebker, R.; Klein, C.; Fleck, E.; Kelle, S. [German Heart Institute Berlin, Department of Internal Medicine/Cardiology, Berlin (Germany); Hamdan, A. [Tel Aviv University, Heart Center, Chaim Sheba Medical Center, Tel Hashomer, Sackler Faculty of Medicine, Tel Aviv (Israel); Schnackenburg, B. [Philips Healthcare, Clinical Science, Hamburg (Germany); Nagel, E. [King' s College London, Department of Cardiovascular Imaging, London (United Kingdom)

    2014-09-15

    To compare contrast doses and acquisition times for late gadolinium enhancement (LGE) imaging at 3.0 T using gadobenate dimeglumine (Gd-BOPTA) in patients with chronic myocardial infarction. Thirty-four patients with chronic myocardial infarction were randomised to 0.10, 0.15 and 0.20 mmol/kg of Gd-BOPTA. T1-weighted inversion recovery gradient echo sequences were performed at 5, 10, 15 and 20 min post-administration of contrast in a 3.0-T scanner. Scar-to-myocardium contrast-to-noise ratio (CNR), scar-to-blood CNR, scar size and image quality were assessed. Imaging at 5 min was associated with a lower scar-to-blood CNR in comparison to 10, 15 and 20 min at 0.10 mmol/kg, and in comparison to 15 and 20 min at 0.20 mmol/kg. At 0.10-mmol/kg, imaging at 5 min yielded smaller infarct sizes in comparison to 15 and 20 min. Finally, at 0.20-mmol/kg, imaging at 5 min was associated with poorer image quality in comparison to later times. In LGE imaging at 3.0 T, low doses of Gd-BOPTA perform equally well as higher doses. Early acquisition (5 min) is associated with lower infarct sizes and image quality. Studies with sufficient diagnostic quality can be obtained after 10 min using 0.10 mmol/kg Gd-BOPTA. (orig.)

  4. Comparison of Gd-Bz-TTDA, Gd-EOB-DTPA, and Gd-BOPTA for dynamic MR imaging of the liver in rat models.

    Science.gov (United States)

    Jaw, Twei-Shiun; Chen, Shih-Hsien; Wang, Yun-Ming; Hsu, Jui-Sheng; Kuo, Yu-Ting; Chiu, Yen-Yu; Tsai, Kun-Bow; Hsieh, Tsyh-Jyi; Liu, Gin-Chung

    2012-03-01

    To evaluate the competitive potential of a new lipophilic paramagnetic complex, Gd-Bz-TTDA [4-benzyl-3,6,10-tri (carboxymethyl)-3,6,10-triazado-decanedioic acid] compared with two other commercially available MR hepatobiliary contrast agents, gadobenate dimeglumine (Gd-BOPTA) and gadoxetic acid (Gd-EOB-DTPA), dynamic MR imaging studies were performed on normal and hepatocellular carcinoma (HCC) rat models using a 1.5-Tesla MR scanner. The results indicate that normal rats that were injected with 0.1 mmol/kg Gd-Bz-TTDA showed significantly more intense and persistent liver enhancement than those that were injected with the same dose of Gd-EOB-DTPA or Gd-BOPTA. All of these agents showed similar enhancement patterns in the implanted HCC. The liver-lesion contrast-to-noise ratios were higher and more persistent in rats that were injected with Gd-Bz-TTDA. These results indicate that Gd-Bz-TTDA is comparable with the commercially available hepatobiliary agents, Gd-EOB-DTPA and Gd-BOPTA, and can result in more intense and prolonged liver enhancement while still providing better liver-lesion discrimination. These results warrant further large-scale studies.

  5. Gd-BOPTA增强60min再延迟扫描对小肝癌的诊断价值%Evaluation of delayed enhanced MRI with Gd-BOPTA in diagnosis of small HCC

    Institute of Scientific and Technical Information of China (English)

    吕涵青; 陈健湘; 谢宗贵; 赵波沣

    2011-01-01

    Objective To investigate the diagnostic value of 60 minutes delayed enhanced MR imaging with Gd- BOPTA, a double- phasic magnetic resonance contrast agent, on the small hepatocellular cacinoma (SHCC).Methods Twenty- five patients with surgery or pathologically proved SHCC underwent MR scan with PHILIPS Intera the 1.5T magnetic resonance scanner.The scan included SE T1WI, FSE T2WI and Gd- BOPTA dynamic enhanced MRI.Dynamic enhanced scanning were done 20 seconds, 1,5 and 60 minutes after Gd- BOPTA injection using THRIVE sequence.The signal intensity of lesions on non- enhanced, dynamic and 60 minutes delayed enhanced MR imaging were observed and analyzed.Results In 25 patients with SHCC, 33 lesions were found.The detection rate ofnon- enhanced, dynamic and 60 minutes delayed enhanced MR imaging were 75.8%, 81.8% and 96.9%, respectively.There was significant difference between 60 minutes delayed enhanced MR imaging and dynamic enhanced MR imaging.Conclusion Gd- BOPTA has an important role in the diagnosis of SHCC, especially to find SHCC of deficient blood supply using 60 minutes delayed enhanced MR imaging.%目的 探讨具有双相增强作用的磁共振对比剂钆贝葡胺(Gd-BOPTA),MRI增强后60 min再延迟扫描对小肝癌(SHCC)的诊断价值.方法 手术或穿刺病理证实为SHCC患者25例,采用Philips Intera 1.5 T磁共振扫描仪.行SE序列T1WI、FSE序列T2WI及Gd-BOPTA快速动态增强多期扫描.Gd-BOPTA增强扫描采用静脉团注快速动态增强扫描,并在团注后20 s、1 min、5 min及60 min行THRIVE扫描.观察分析MRI平扫、Gd-BOPTA三期增强扫描及60 min再延迟扫描病灶的信号改变,并进行统计学处理.结果 25例患者,共发现SHCC病灶33个;对SHCC病灶的检出率,MRI平扫为75.8%(25/33),Gd-BOPTA三期增强为81.8%(27/33),Gd-BOPTA三期增强+60 min再延迟扫描为96.9%(32/33).Gd-BOPTA三期增强联合60 min再延迟扫描对SHCC病灶的检出率明显优于Gd-BOPTA三期增强,两者之

  6. Hepatic hemangiomas: Difference in enhancement pattern on 3T MR imaging with gadobenate dimeglumine versus gadoxetate disodium

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    Gupta, Rajan T., E-mail: rajan.gupta@duke.edu [Duke University Medical Center, Department of Radiology, DUMC 3808, Durham, NC 27710 (United States); Marin, Daniele; Boll, Daniel T.; Husarik, Daniela B.; Davis, Drew E.; Feuerlein, Sebastian; Merkle, Elmar M. [Duke University Medical Center, Department of Radiology, DUMC 3808, Durham, NC 27710 (United States)

    2012-10-15

    Purpose: To compare intraindividual differences in enhancement pattern of hepatic hemangiomas between gadobenate dimeglumine (Gd-BOPTA) and gadoxetate disodium (Gd-EOB-DTPA)-enhanced 3T MR imaging. Materials and methods: This is a HIPAA-compliant, IRB-approved retrospective study with waiver for informed consent granted. From 10/07 to 5/09, 10 patients (2 males, 8 females; mean age, 57.3 years) with 15 hepatic hemangiomas (mean diameter, 4.4 ± 5.6 cm) underwent both Gd-BOPTA- and Gd-EOB-DTPA-enhanced 3T MR imaging (mean interval, 266 days; range, 38–462 days). Diagnosis of hemangioma was based on strict imaging criteria. MR imaging was obtained during three arterial, portal venous, and up to four delayed phases. During each phase, hemangioma-to-liver contrast-to-noise ratio (CNR) was measured for each lesion on both examinations. Statistical analysis was performed using paired Student's t-test. Results: Hemangioma-to-liver CNR peaked during the portal venous phase (Gd-BOPTA: 48.9 ± 65.8, Gd-EOB-DTPA: 0.7 ± 3.8). During all imaging phases except the first arterial phase, hemangioma-to-liver CNR was significantly lower on Gd-EOB-DTPA-enhanced compared to Gd-BOPTA-enhanced MR images (p < 0.05). Notably, Gd-EOB-DTPA yielded negative hemangioma-to-liver CNR (−2.5 ± 2.4) compared to Gd-BOPTA (40.7 ± 56.4) during the first delayed phase (7–8 min after contrast administration), remaining negative for the rest of the delayed phases (up to 26 min after contrast administration). Conclusion: The enhancement patterns of hepatic hemangiomas differs significantly between Gd-BOPTA and Gd-EOB-DTPA-enhanced 3T MR imaging. The smaller dose, shorter plasma half-life, and increased hepatobiliary uptake of Gd-EOB-DTPA leads to a negative CNR of hemangioma-to-liver on delayed phases and could create an imaging pitfall with this agent.

  7. Gadobenate-dimeglumine-enhanced magnetic resonance imaging for hepatic lesions in children

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    Chavhan, Govind B.; Mann, Erika [The Hospital for Sick Children and University of Toronto, Department of Diagnostic Imaging, Toronto (Canada); Kamath, Binita M. [The Hospital for Sick Children and University of Toronto, Division of Gastroenterology, Hepatology and Nutrition, Toronto (Canada); Babyn, Paul S. [Royal University Hospital, Department of Medical Imaging, Saskatoon (Canada)

    2014-10-15

    Magnetic resonance imaging enhanced by hepatocyte-specific contrast media has been found useful to characterize liver lesions in adults and children. To present our experience with gadobenate dimeglumine (Gd-BOPTA)-enhanced MRI for evaluation of focal liver lesions in children. We retrospectively reviewed gadobenate-dimeglumine-enhanced MR images obtained for evaluation of suspected hepatic lesions in 30 children. Signal characteristics on various sequences including 45- to 60-min hepatobiliary phase images were noted by two radiologists. Chart review identified relevant clinical details including history of cancer treatment, available pathology and stability of lesion size on follow-up imaging. Of the 30 children who had gadobenate-enhanced MRI, 26 showed focal lesions. Diagnoses in 26 children were focal nodular hyperplasia (FNH) in 15, hemangiomas in 3, regenerating nodules in 3, focal fatty infiltration in 2, indeterminate lesions in 3, and one patient each with adenomas, hepatoblastoma and metastasis. Two patients had multiple diagnoses. All FNH lesions (39), all regenerative nodules (19) and an indeterminate lesion were iso- or hyperintense on hepatobiliary-phase images while all other lesions (28) were hypointense to hepatic parenchyma. The average follow-up period was 21.7 months. Our experience with gadobenate-enhanced MRI indicates potential utility of gadobenate in the evaluation of pediatric hepatic lesions in differentiating FNH and regenerating nodules from other lesions. (orig.)

  8. Ultra low-dose of gadobenate dimeglumine for late gadolinium enhancement (LGE) imaging in acute myocardial infarction: a feasibility study.

    Science.gov (United States)

    Galea, Nicola; Francone, Marco; Zaccagna, Fulvio; Ciolina, Federica; Cannata, David; Algeri, Emanuela; Agati, Luciano; Catalano, Carlo; Carbone, Iacopo

    2014-12-01

    To assess the feasibility of using an ultra-low dose (0.05 mmol/kg of body weight [BW]) of high relaxivity contrast agent for late gadolinium enhancement (LGE) imaging in patients with acute myocardial infarction (AMI). 17 consecutive patients (mean age, 60.1 ± 10.3 years) with ST-segment elevation AMI underwent two randomized cardiac magnetic resonance studies (exam intervals between 24 and 48h) on a 1.5T unit during the first week after the event using gadobenate dimeglumine (Gd-BOPTA) at the dose of 0.1 mmol/kg BW (standard dose or SD group) and 0.05 mmol/kg BW (half dose or HD group). Image quality was qualitatively assessed. Quantitative analysis of LGE were performed by measuring signal intensity (SI), signal-to-noise ratio (SNR) in the infarcted myocardium (IM), non-infarcted myocardium (N-IM) and left ventricular cavity (LVC) in images acquired at 1, 3, 5, 10, 15 and 20 min after administration of Gd-BOPTA using both contrast media protocol. Contrast-to-noise ratio (CNR) between IM and N-IM (CNR IM/N-IM) and between IM and LVC (CNR IM/LVC) were also quantified for each time point. Moreover the extent of infarcted myocardium was measured. 102 LGE images were evaluated for each dose group. Quality score was significantly higher for SD at 1, 15 and 20 min (0.002

  9. T1 mapping of the myocardium: intra-individual assessment of post-contrast T1 time evolution and extracellular volume fraction at 3T for Gd-DTPA and Gd-BOPTA

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    Kawel Nadine

    2012-04-01

    Full Text Available Abstract Purpose Myocardial T1 relaxation time (T1 time and extracellular volume fraction (ECV are altered in patients with diffuse myocardial fibrosis. The purpose of this study was to perform an intra-individual assessment of normal T1 time and ECV for two different contrast agents. Methods A modified Look-Locker Inversion Recovery (MOLLI sequence was acquired at 3 T in 24 healthy subjects (8 men; 28 ± 6 years at mid-ventricular short axis pre-contrast and every 5 min between 5-45 min after injection of a bolus of 0.15 mmol/kg gadopentetate dimeglumine (Gd-DTPA; Magnevist® (exam 1 and 0.1 mmol/kg gadobenate dimeglumine (Gd-BOPTA; Multihance® (exam 2 during two separate scanning sessions. T1 times were measured in myocardium and blood on generated T1 maps. ECVs were calculated as ΔR1myocardium/ΔR1blood*1−hematocrit. Results Mean pre-contrast T1 relaxation times for myocardium and blood were similar for both the first and second CMR exam (p > 0.5. Overall mean post-contrast myocardial T1 time was 15 ± 2 ms (2.5 ± 0.7% shorter for Gd-DTPA at 0.15 mmol/kg compared to Gd-BOPTA at 0.1 mmol/kg (p  0.05. Between 5 and 45 minutes after contrast injection, mean ECV values increased linearly with time for both contrast agents from 0.27 ± 0.03 to 0.30 ± 0.03 (p pre-contrast myocardial T1 relaxation time (CV 4.5% [exam 1] and 3.0% [exam 2], respectively. ECV with Gd-DTPA was highly correlated to ECV by Gd-BOPTA (r = 0.803; p  Conclusion In comparison to pre-contrast myocardial T1 relaxation time, variation in ECV values of normal subjects is larger. However, absolute differences in ECV between Gd-DTPA and Gd-BOPTA were small and rank correlation was high. There is a small and linear increase in ECV over time, therefore ideally images should be acquired at the same delay after contrast injection.

  10. Ultra low-dose of gadobenate dimeglumine for late gadolinium enhancement (LGE) imaging in acute myocardial infarction: A feasibility study

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    Galea, Nicola, E-mail: nicola.galea@uniroma1.it [Department of Radiological Sciences, Pathology and Oncology, Policlinico Umberto I, “Sapienza” University of Rome, Viale Regina Elena 315, 00161 Rome (Italy); Francone, Marco, E-mail: marco.francone@uniroma1.it [Department of Radiological Sciences, Pathology and Oncology, Policlinico Umberto I, “Sapienza” University of Rome, Viale Regina Elena 315, 00161 Rome (Italy); Zaccagna, Fulvio, E-mail: f.zaccagna@gmail.com [Department of Radiological Sciences, Pathology and Oncology, Policlinico Umberto I, “Sapienza” University of Rome, Viale Regina Elena 315, 00161 Rome (Italy); Ciolina, Federica, E-mail: federica.ciolina@gmail.com [Department of Radiological Sciences, Pathology and Oncology, Policlinico Umberto I, “Sapienza” University of Rome, Viale Regina Elena 315, 00161 Rome (Italy); Cannata, David, E-mail: davidrum@yahoo.it [Department of Radiological Sciences, Pathology and Oncology, Policlinico Umberto I, “Sapienza” University of Rome, Viale Regina Elena 315, 00161 Rome (Italy); Algeri, Emanuela, E-mail: emanuela_algeri@yahoo.com [Service de Radiologie et Imagerie Cardiovasculaire, Hôpital Cardiologique, Centre Hospitalier Régional et Universitaire de Lille, Avenue Oscar Lambret, 59037 Lille Cedex (France); Agati, Luciano, E-mail: luciano.agati@uniroma1.it [Department of Cardiovascular, Respiratory, Nephrologic, Anestesiologic and Geriatric Sciences, Sapienza University of Rome, Policlinico Umberto I, Via del Policlinico 165, 00161 Rome, Rome (Italy); and others

    2014-12-15

    Highlights: • We compared two gadolinium dose for late enhancement imaging in acute infarction. • We evaluated image quality both qualitatively and quantitatively. • Low dose regimen is feasible and provides better image quality at 5–10 min delay. • Standard dose warrants better image quality and should be routinely preferred. - Abstract: Purpose: To assess the feasibility of using an ultra-low dose (0.05 mmol/kg of body weight [BW]) of high relaxivity contrast agent for late gadolinium enhancement (LGE) imaging in patients with acute myocardial infarction (AMI). Materials and methods: 17 consecutive patients (mean age, 60.1 ± 10.3 years) with ST-segment elevation AMI underwent two randomized cardiac magnetic resonance studies (exam intervals between 24 and 48 h) on a 1.5 T unit during the first week after the event using gadobenate dimeglumine (Gd-BOPTA) at the dose of 0.1 mmol/kg BW (standard dose or SD group) and 0.05 mmol/kg BW (half dose or HD group). Image quality was qualitatively assessed. Quantitative analysis of LGE were performed by measuring signal intensity (SI), signal-to-noise ratio (SNR) in the infarcted myocardium (IM), non-infarcted myocardium (N-IM) and left ventricular cavity (LVC) in images acquired at 1, 3, 5, 10, 15 and 20 min after administration of Gd-BOPTA using both contrast media protocol. Contrast-to-noise ratio (CNR) between IM and N-IM (CNR IM/N-IM) and between IM and LVC (CNR IM/LVC) were also quantified for each time point. Moreover the extent of infarcted myocardium was measured. Results: 102 LGE images were evaluated for each dose group. Quality score was significantly higher for SD at 1, 15 and 20 min (0.002 < p < 0.046) and for HD at 5 min (p = 0.013). SNR has been higher in the SD group compared to the HD group even though not statistically significant at any time-point for both IM (SD vs. HD: 87.7 ± 73 vs. 65 ± 66; 0.15 < p < 0.38) and N-IM (SD vs. HD: 22 ± 61 vs. 9.9 ± 6.5; 0.09 < p < 0.43). LVC SNR was

  11. Efficacy of gadobenate dimeglumine vs gadopentetate dimeglumine in contrastenhanced magnetic resonance imaging for diagnosis of solitary brain metastases%钆贝葡胺和钆喷酸葡胺在磁共振增强扫描诊断单发脑转移瘤中照研究

    Institute of Scientific and Technical Information of China (English)

    王庆军; 王勇; 徐贤; 肖慧; 马林

    2011-01-01

    目的 比较钆贝葡胺(Gd-BOPTA)与钆喷酸葡胺(Gd-DTPA)在MRIT1WI增强扫描诊断单发脑转移瘤(solitary brain metastases,SBM)的价值.方法 我们采用自身对照的研究方法,分别以相同浓度的钆贝葡胺和钆喷酸葡胺对比剂(0.1mmol/kg),对27例SBM的患者进行MRI T1WI增强扫描.所有患者均在同一台3.0-T的磁共振仪上分别完成2次颅脑平扫和增强扫描,第1次增强扫描使用钆喷酸葡胺对比剂,第2次使用钆贝葡胺对比剂.3名医生独自、盲法评价2次检查中SBM增强效果.评价指标分为定性指标(增强轮廓、增强范围、增强内部形态和增强程度)及定量指标(病灶/正常脑增强比,对比噪声比和增强百分比).结果 在病灶增强轮廓、增强范围、增强后内部形态和增强程度方面,钆贝葡胺全面优于钆喷酸葡胺(P<0.05).相对于钆喷酸葡胺,钆贝葡胺在病灶/正常脑增强比(P<0.05),对比噪声比(P<0.05)和增强百分比方面(P<0.05)亦优于钆喷酸葡胺.结论 使用相同浓度的钆贝葡胺与钆喷酸葡胺对SBM进行MRI T1WI增强扫描,钆贝葡胺增强效果优于钆喷酸葡胺.%Objective To compare gadobenate dimeglumine (Gd-BOPTA) and gadopentetate dimeglumine (Gd-DTPA) for their efficacy as contrast agents in contrast-enhanced magnetic resonance imaging (MRI) for diagnosis of solitary brain metastases (SBM). Methods We conducted an intra-individual study of contrast-enhanced T1-weighted MRI (TiWI) data from 27 Chinese patients with suspected SBM to compare the enhancement findings of two different MRI contrast agents, Gd-BOPTA and Gd-DTPA (at equivalent doses of 0.1 mmol/kg), for the detection of SBM. All the patients underwent two identical MRI examinations on a 3.0-T MRI scanner first with Gd-DTPA and then with Gd-BOPTA. Evaluation of the contrast enhancement was performed qualitatively (border delineation, extent, internal morphology, and contrast enhancement) and quantitatively (lesion

  12. Is hepatotropic contrast enhanced MR a more effective method in differential diagnosis of hemangioma than multi-phase CT and unenhanced MR?

    Science.gov (United States)

    2011-01-01

    Background Cavernous hemangiomas are the most frequent neoplasms of the liver and in routine clinical practice they often need to be differentiated from malignant tumors and other benign focal lesions. The purpose of this study is to evaluate whether diagnostic accuracy of magnetic resonance imaging (MRI) of hepatic hemangiomas, showing atypical pattern on US, improves with the use of Gd-BOPTA in comparison with contrast-enhanced multi-phase computed tomography (CT). Methods 178 consecutive patients with ambiguous hepatic masses showing atypical hyperechoic pattern on grey-scale US, underwent unenhanced and contrast-enhanced multi-phase multi-detector CT and MR (1.5T) with the use of liver-specific contrast medium gadobenate dimeglumine (Gd-BOPTA). After intravenous contrast administration arterial (HAP), venous-portal (PVP), equilibrium phases (EP) both in CT and MR and additionally hepatobiliary phase (HBP) in MR were obtained. 398 lesions have been detected including 99 hemangiomas and 299 other lesions. Results In non-enhanced MDCT examination detection of hemangiomas was characterized by sensitivity of 76%, specificity of 90%, PPV of 71%, NPV of 92% and accuracy of 86%. Non-enhanced MR examination showed sensitivity of 98%, specificity of 99%, PPV of 99%, NPV of 99% and accuracy of 99%. After intravenous administration of contrast medium in MR the mentioned above parameters did not increase significantly. Conclusion Gd-BOPTA-enhanced MR in comparison with unenhanced MRI does not improve diagnostic accuracy in discriminating hemangiomas that show non-specific appearance in ultrasound examination. Unenhanced MR as a method of choice should directly follow US in course of diagnostic algorithm in differentiation of hemangiomas from other liver tumors. PMID:21504593

  13. Is hepatotropic contrast enhanced MR a more effective method in differential diagnosis of hemangioma than multi-phase CT and unenhanced MR?

    Directory of Open Access Journals (Sweden)

    Markiet Karolina

    2011-04-01

    Full Text Available Abstract Background Cavernous hemangiomas are the most frequent neoplasms of the liver and in routine clinical practice they often need to be differentiated from malignant tumors and other benign focal lesions. The purpose of this study is to evaluate whether diagnostic accuracy of magnetic resonance imaging (MRI of hepatic hemangiomas, showing atypical pattern on US, improves with the use of Gd-BOPTA in comparison with contrast-enhanced multi-phase computed tomography (CT. Methods 178 consecutive patients with ambiguous hepatic masses showing atypical hyperechoic pattern on grey-scale US, underwent unenhanced and contrast-enhanced multi-phase multi-detector CT and MR (1.5T with the use of liver-specific contrast medium gadobenate dimeglumine (Gd-BOPTA. After intravenous contrast administration arterial (HAP, venous-portal (PVP, equilibrium phases (EP both in CT and MR and additionally hepatobiliary phase (HBP in MR were obtained. 398 lesions have been detected including 99 hemangiomas and 299 other lesions. Results In non-enhanced MDCT examination detection of hemangiomas was characterized by sensitivity of 76%, specificity of 90%, PPV of 71%, NPV of 92% and accuracy of 86%. Non-enhanced MR examination showed sensitivity of 98%, specificity of 99%, PPV of 99%, NPV of 99% and accuracy of 99%. After intravenous administration of contrast medium in MR the mentioned above parameters did not increase significantly. Conclusion Gd-BOPTA-enhanced MR in comparison with unenhanced MRI does not improve diagnostic accuracy in discriminating hemangiomas that show non-specific appearance in ultrasound examination. Unenhanced MR as a method of choice should directly follow US in course of diagnostic algorithm in differentiation of hemangiomas from other liver tumors.

  14. Gadopentetate-dimeglumine-enhanced MR imaging of osteonecrosis and osteochondritis dissecans of the elbow: initial experience.

    Science.gov (United States)

    Peiss, J; Adam, G; Casser, R; Urhahn, R; Günther, R W

    1995-01-01

    Magnetic resonance imaging (MRI) was performed on seven patients with aseptic osteonecrosis (n = 4) and osteochondritis dissecans (OCD; n = 3) of the elbow. Precontrast MRI was superior to plain radiographs, which did not show any abnormality in three cases of osteonecrosis. On gadopentetate-dimeglumine-enhanced T1-weighted images, which were obtained in three patients with osteonecrosis and three patients with OCD, all cases of osteonecrosis demonstrated homogeneous enhancement of the lesions. All cases of OCD were diagnosed on plain radiographs. On MRI one showed significant enhancement of the loose body. In another case an incompletely enhancing loose body was surrounded by a diffusely enhancing region. In the third patient only a small marginal enhancement of the defect was observed. Our results suggest that MRI can improve the accuracy in diagnosis of aseptic osteonecrosis of the elbow. The use of gadopentetate dimeglumine allows the viability of the lesions or the loose bodies to be demonstrated and reparative tissue to be detected.

  15. CE-Magnetic Resonance mammography for the evaluation of the contralateral breast in patients with diagnosed breast cancer; Ruolo della Risonanza Magnetica con Gd-BOPTA nella valutazione della mammella controlaterale in pazienti con tumore recentemente diagnosticato

    Energy Technology Data Exchange (ETDEWEB)

    Pediconi, Federica; Venditti, Fiammetta; Padula, Simona; Roselli, Antonella; Moriconi, Enrica; Catalano, Carlo; Passariello, Roberto [La Sapienza Univ., Roma (Italy). Dipartimento di scienze radiologiche; Giacomelli, Laura [La Sapienza Univ., Roma (Italy). Dipartimento di scienze chirurgiche

    2005-07-15

    Purpose. To evaluate the role of contrast-enhanced Magnetic Resonance Mammography (MRM) in the evaluation of the contralateral breast in patients with recently diagnosed breast cancer. Materials and methods. Fifty patients with proved unilateral breast cancer, with a negative contralateral breast at physical examination, ultrasound and mammography, were studied with a 1.5 T magnet (Siemens, Vision Plus, Germany). A bilateral breast surface coil was used. Dynamic 3D Flash T1-weighted sequences were acquired in the axial plane before and 0, 2, 4, 6 and 8 minutes after the administration of 0.1 mmol/kg of Gd-BOPTA at a flow rate of 2 ml/s followed by 10 ml of saline. The level of suspicion was reported on a scale from 0 to 5 following the BI-RADS classification, based on lesion morphology and kinetic features. The results were compared with the histological findings after biopsy or surgery. Results. Fourteen out of 50 patients (28%) had contralateral lesions identified on MRM. Biopsy was performed in four of them for suspicious lesions (BI-RADS 4) while 10 patients underwent surgery because of highly suggestive malignant lesions (BI-RADS 5). Histology diagnosed three fibroadenomas, 5 ductal carcinoma in situ, 2 lobular carcinomas in situ, 3 invasive ductal carcinomas and 1 invasive lobular carcinoma. Contrast enhanced MRM yielded no false negative and three false positives. Conclusions. Our results demonstrate a very good accuracy of Magnetic Resonance Mammography in the detection of synchronous contralateral cancer in patients with newly diagnosed breast cancer. Therefore, contrast-enhanced MRM could be introduced to screen patients with proven breast cancer before they under-go surgery. [Italian] Scopo. Definire il ruolo della Risonanza Magnetica nella valutazione della mammella contro laterale in pazienti con tumore della mammella recentemente diagnosticato. Materiale e metodi. Cinquanta pazienti con tumore monolaterale della mammella e mammella controlaterale

  16. Three-dimensional multiphase time-resolved low-dose contrast-enhanced magnetic resonance angiography using TWIST on a 32-channel coil at 3 T: a quantitative and qualitative comparison of a conventional gadolinium chelate with a high-relaxivity agent.

    Science.gov (United States)

    Giesel, Frederik L; Runge, Val; Kirchin, Miles; Mehndiratta, Amit; Gerigk, Lars; Corell, Body; von Gall, Carl; Kauczor, Hans-Ulrich; Essig, Marco

    2010-01-01

    To evaluate low-dose contrast-enhanced magnetic resonance angiography (CE-MRA) at high temporal and spatial resolution for imaging of abdominal vascular structures. Contrast-enhanced magnetic resonance angiography (TWIST [time-resolved angiography with interleaved stochastic trajectories]) was performed in 8 male New Zealand white rabbits at 3 T using a prototype 32-channel coil. Gadoteridol (Gd-HP-DO3A, ProHance; Bracco Imaging SpA, Milan, Italy) and the high-relaxivity agent gadobenate dimeglumine (Gd-BOPTA, MultiHance; Bracco Imaging SpA), each at a dose of 0.04 mmol/kg body weight, were used in an intraindividual comparison. Quantitative analysis of contrast-to-noise ratio (CNR) was performed in regions of interest placed in the aorta and the adjacent tissues. The image quality in the aorta, external iliac artery, and vena cava was categorized by 2 independent blinded readers from excellent (1) to poor (3). A significantly (P Qualitative rating showed the image quality to be excellent for gadobenate dimeglumine and adequate for gadoteridol. Time-resolved CE-MRA performed at 3 T with a 32-channel volume coil can be improved using the high-relaxivity agent gadobenate dimeglumine, which increases quality and quantity of vessel enhancement.

  17. Contrast-enhanced MRA of the renal and aorto-iliac-femoral arteries: Comparison of gadobenate dimeglumine and gadofosveset trisodium

    Energy Technology Data Exchange (ETDEWEB)

    Iezzi, Roberto [Department of Radiology, Universita G. D' Annunzio, Chieti (Italy); Soulez, Gilles [Centre Hospitalier de L' Universite De Montreal, Montreal (Quebec) (Canada); Thurnher, Siegfried [Department of Radiology, Hospital Brothers of St. John of God, Vienna (Austria); Schneider, Guenther [Department of Diagnostic and Interventional Radiology, University Hospital of Saarland, Homburg/Saar (Germany); Kirchin, Miles A., E-mail: miles.kirchin@bracco.com [Worldwide Medical and Regulatory Affairs, Bracco Imaging SpA, Via E. Folli, 50, Milan 20134 (Italy); Shen, Ningyan; Pirovano, Gianpaolo; Spinazzi, Alberto [Worldwide Medical and Regulatory Affairs, Bracco Diagnostics, Princeton, NJ (United States)

    2011-02-15

    Rationale and objectives: Dedicated contrast agents are now available for contrast-enhanced magnetic resonance angiography (CE-MRA). This study retrospectively compares the safety and diagnostic performance data from Phase III regulatory trials performed to evaluate gadobenate dimeglumine (MultiHance) and gadofosveset trisodium (Vasovist) for renal and peripheral CE-MRA. Materials and methods: Similar examination and blinded assessment methodology was utilized in all studies to determine the safety and diagnostic performance of the agents for detection of significant (>50%) steno-occlusive disease. Digital Subtraction Angiography (DSA) was used as the standard of truth. Diagnostic performance data (sensitivity, specificity, predictive values [PVs], and likelihood ratios [LRs]) were compared (Chi-square test). Results: CE-MRA with gadobenate dimeglumine was more specific (92.4% vs. 80.5%, p < 0.0001) and accurate (83.6% vs. 77.1%, p = 0.022) than CE-MRA with gadofosveset in the detection of significant renal artery stenosis. The average sensitivity was higher for gadofosveset (74.4% vs. 67.3%, p = 0.011) in peripheral vessels although gadobenate dimeglumine was more specific (93.0% vs. 88.2%, p < 0.0001) with no difference in accuracy (86.6% vs. 86.3%, p = 0.66). PPVs were higher (p < 0.0001) for gadobenate dimeglumine in both vascular territories. Pre- to post-test shifts in the probability of detecting significant disease were greater after gadobenate dimeglumine. Adverse events in the renal and peripheral studies were reported by 9.2% and 7.7% of patients after gadobenate dimeglumine compared with 30.3% and 22.1% of patients after gadofosveset. Conclusion: The diagnostic performance of CE-MRA for the detection of significant steno-occlusive disease is similar with gadofosveset and gadobenate dimeglumine although the rate of adverse events appears higher with gadofosveset.

  18. Evaluation of carotid vessel wall enhancement with image subtraction after gadobenate dimeglumine-enhanced MR angiography

    Energy Technology Data Exchange (ETDEWEB)

    Sardanelli, Francesco [Department of Medical and Surgical Sciences, University of Milan School of Medicine, via Morandi 30, 20097 San Donato Milanese, Milan (Italy); Unit of Radiology, IRCCS Policlinico San Donato, via Morandi 30, 20097 San Donato Milanese, Milan (Italy)], E-mail: f.sardanelli@grupposandonato.it; Di Leo, Giovanni [Unit of Radiology, IRCCS Policlinico San Donato, via Morandi 30, 20097 San Donato Milanese, Milan (Italy)], E-mail: gianni.dileo77@virgilio.it; Aliprandi, Alberto [Unit of Radiology, IRCCS Policlinico San Donato, via Morandi 30, 20097 San Donato Milanese, Milan (Italy)], E-mail: a.aliprandi@grupposandonato.it; Flor, Nicola [Department of Diagnostic and Interventional Radiology, University of Milan School of Medicine, San Paolo Hospital, via di Rudini 8, 20142 Milan (Italy)], E-mail: flornic@hotmail.com; Papini, Giacomo D.E. [Unit of Radiology, IRCCS Policlinico San Donato, via Morandi 30, 20097 San Donato Milanese, Milan (Italy)], E-mail: giacomo.papini@fastwebnet.it; Roccatagliata, Luca [Unit of Radiology, IRCCS Policlinico San Donato, via Morandi 30, 20097 San Donato Milanese, Milan (Italy); Department of Neuroscience, Ophthalmology and Genetics, University of Genoa, via De Toni 5, 16132 Genoa (Italy)], E-mail: lroccatagliata@neurologia.unige.it; Cotticelli, Biagio [Unit of Radiology, IRCCS Policlinico San Donato, via Morandi 30, 20097 San Donato Milanese, Milan (Italy)], E-mail: neurobiagio@tiscali.it; Nano, Giovanni [Department of Medical and Surgical Sciences, University of Milan School of Medicine, via Morandi 30, 20097 San Donato Milanese, Milan (Italy); Unit of Vascular Surgery, IRCCS Policlinico San Donato, via Morandi 30, 20097 Milan (Italy)], E-mail: gianni.nano@libero.it; Cornalba, Gianpaolo [Department of Diagnostic and Interventional Radiology, University of Milan School of Medicine, San Paolo Hospital, via di Rudini 8, 20142 Milan (Italy)], E-mail: gianpaolo.cornalba@unimi.it

    2009-06-15

    Objectives: This study was aimed at testing the value of image subtraction for evaluating carotid vessel wall enhancement in contrast-enhanced MR angiography (MRA). Materials and methods: IRB approval was obtained. The scans of 81 consecutive patients who underwent carotid MRA with 0.1 mmol/kg of gadobenate dimeglumine were reviewed. Axial carotid 3D T1-weighted fast low-angle shot sequence before and 3 min after contrast injection were acquired and subtracted (enhanced minus unenhanced). Vessel wall enhancement was assigned a four-point score using native or subtracted images from 0 (no enhancement) to 3 (strong enhancement). Stenosis degree was graded according to NASCET. Results: With native images, vessel wall enhancement was detected in 20/81 patients (25%) and in 20/161 carotids (12%), and scored 2.0 {+-} 0.6 (mean {+-} standard deviation); with subtracted images, in 21/81 (26%) and 22/161 (14%), and scored 2.5 {+-} 0.6, respectively (P < 0.001, Sign test). The overall stenosis degree distribution was: mild, 41/161 (25%); moderate, 77/161 (48%); severe, 43/161 (27%). Carotids with moderate stenosis showed vessel wall enhancement with a frequency (17/77, 22%) significantly higher than that observed in carotids with mild stenosis (1/41, 2%) (P = 0.005, Fisher exact test) and higher, even though with borderline significance (P = 0.078, Fisher exact test), than that observed in carotids with severe stenosis (4/43, 9%). Conclusion: Roughly a quarter of patients undergoing carotid MRA showed vessel wall enhancement. Image subtraction improved vessel wall enhancement conspicuity. Vessel wall enhancement seems to be an event relatively independent from the degree of stenosis. Further studies are warranted to define the relation between vessel wall enhancement and histopathology, inflammatory status, and instability.

  19. Safety and adverse effects during 24 hours after contrast-enhanced MRI with gadobenate dimeglumine (MultiHance {sup registered}) in children

    Energy Technology Data Exchange (ETDEWEB)

    Schneider, Guenther; Schuerholz, Hellmut; Buecker, Arno; Fries, Peter [Homburg University Hospital, Homburg, Saar (Germany); Kirchin, Miles A. [Bracco Imaging SpA, Milan (Italy)

    2013-02-15

    Gadolinium-based MR contrast agents have long been considered safe for routine diagnostic imaging. However, the advent of nephrogenic systemic fibrosis (NSF) among certain patients with severe renal insufficiency has brought the issue of safety into question. Nowhere is safety of greater concern than among children who frequently require multiple contrast-enhanced MRI examinations over an extended period of time. To retrospectively evaluate the safety of gadobenate dimeglumine for contrast-enhanced (CE) MRI across a range of indications. Two hundred pediatric inpatients (age: 4 days to 15 years) underwent CE MRI as part of clinical routine. The children received a gadobenate dimeglumine dose of either 0.05 mmol/kg body weight (liver, abdominal imaging, musculoskeletal imaging, brain and other rare indications) or 0.1 mmol/kg bodyweight (cardiovascular imaging, MR-urography). Young (< 8 years) children with congenital heart disease were intubated and underwent MRA evaluation with controlled ventilation. Monitoring for adverse events was performed for at least 24 h after each gadobenate dimeglumine injection. Depending on clinical necessity, laboratory measurements and, in some cases, vital sign and ECG determinations were made before and after contrast injection. Safety was evaluated by age group, indication and dose administered. No clinically adverse events were reported among children who had one MRI scan only or among children who had several examinations. There were no changes in creatinine or bilirubin levels even in very young children. No adverse events were recorded during the first 24 h following administration of gadobenate dimeglumine in 200 children. (orig.)

  20. Intraindividual quantitative and qualitative comparison of gadopentetate dimeglumine and gadobutrol in time-resolved contrast-enhanced 4-dimensional magnetic resonance angiography in minipigs.

    Science.gov (United States)

    Hadizadeh, Dariusch Reza; Jost, Gregor; Pietsch, Hubertus; Weibrecht, Martin; Perkuhn, Michael; Boschewitz, Jack Maria; Keil, Vera Catharina; Träber, Frank; Kukuk, Guido Matthias; Schild, Hans Heinz; Willinek, Winfried Albert

    2014-07-01

    The concentration and relaxivities of contrast agents affect quantitative and qualitative image quality in contrast-enhanced time-resolved 4-dimensional magnetic resonance angiography (4D-MRA). Gadobutrol has a high relaxivity and is the only gadolinium (Gd)-based contrast agent approved for clinical use at a 1 M concentration. This promises to confer superior bolus characteristics by generating a steeper and shorter bolus with a higher peak Gd concentration. The purpose of this study was to quantitatively examine bolus characteristics of 1 M gadobutrol compared with 0.5 M gadopentetate dimeglumine and to evaluate image quality in thoracoabdominal 4D-MRA. A total of 7 Goettingen minipigs received dynamic computed tomography (CT) on a clinical 64-slice CT (transverse slices, 80 kV, 20 seconds, 0.3 s/dynamic frame) and 4D-MRA (time-resolved imaging with stochastic trajectories; 1. transverse slices, 30 seconds, 0.49 s/frame; 2. coronal slices, 70 seconds, 1.3 s/frame) on a 1.5-T clinical whole-body magnetic resonance imaging under general anesthesia using gadopentetate dimeglumine and gadobutrol in an intraindividual comparative study. Computed tomography attenuations were converted into Gd concentrations on the basis of previous phantom experiments. Quantitative analysis included measurements of the full width at half maximum, time-to-peak intervals, and peak of each bolus in dynamic CT and transverse 4D-MRA. These studies were carried out at equivalent contrast agent flow rates of 1 mL/s. Quantitative analysis (7 arteries and veins) and qualitative image analysis were performed on coronal thoracoabdominal 4D-MRA studies carried out at flow rates of 1 mL/s and, in the case of gadopentetate dimeglumine, also at molarity-adjusted flow rates of 2 mL/s. The bolus in both transverse 4D-MRA and dynamic CT was significantly narrower (full width at half maximum), earlier (time to peak), and higher (signal intensity enhancement in 4D-MRA, Gd concentration in dynamic CT) when

  1. Gadobenate dimeglumine (MultiHance) in MR angiography: an in-vitro phantom comparison with gadopentetate dimeglumine (Magnevist) at different concentrations

    Energy Technology Data Exchange (ETDEWEB)

    Johansson, Lars; Ahlstroem, Haakan [Department of Radiology, Uppsala University Hospital, Uppsala (Sweden)], E-mail: hakan.ahlstrom@akademiska.se; Kirchin, Miles A. [Worldwide Medical and Regulatory Affairs, Bracco Imaging SpA, Milan (Italy)

    2012-12-15

    Background. Numerous clinical studies suggest that gadobenate dimeglumine is diagnostically superior to other gadolinium chelates for MR imaging applications, including contrast-enhanced MR angiography (CE-MRA). However, confirmatory in-vitro phantom studies have thus far been lacking. Purpose. To evaluate the difference in signal intensity achieved with the high-relaxivity MR contrast agent gadobenate dimeglumine (MultiHance) relative to that achieved with the standard-relaxivity non-specific agent gadopentetate dimeglumine (Magnevist) at different concentrations using an in-vitro phantom study design. Material and Methods. Test tubes with whole human blood were prepared with concentrations of gadobenate dimeglumine or gadopentetate dimeglumine ranging from 0 to 12 mM. A three-dimensional (3D) T1-weighted gradient echo sequence normally used for CE-MRA of the renal arteries was performed at flip angles of 25 deg and 35 deg. The signal-to-noise ratio (SNR) was calculated for all concentrations of both contrast agents. Furthermore a Look-Locker sequence was used and quantitative T1 mapping was performed for all the test tubes. The contrast agent concentration in the aorta was simulated using previously published data on T1 in the aorta during the first pass of a contrast agent. The differences between gadobenate dimeglumine and gadopentetate dimeglumine were compared at the simulated concentrations. Results. The SNR achieved with gadobenate dimeglumine was consistently greater than that achieved with gadopentetate dimeglumine at all concentrations. An improvement of 15-25% in SNR was obtained when increasing the flip angle from 25 deg to 35 deg. The relative improvement in SNR with gadobenate dimeglumine relative to gadopentetate dimeglumine ranged from 25-72% and was markedly greater at lower concentrations with a flip angle of 35 deg. Conclusion. Our findings suggest that the relative benefit of gadobenate dimeglumine over gadopentetate dimeglumine for CE

  2. Optimisation of a high-resolution whole-body MR angiography protocol with parallel imaging and biphasic administration of a single bolus of Gd-BOPTA: preliminary experience in the systemic evaluation of atherosclerotic burden in patients referred for endovascular procedures.

    Science.gov (United States)

    Napoli, A; Anzidei, M; Marincola, B Cavallo; Zaccagna, F; Geiger, D; Di Paolo, P L; Zini, C; Catalano, C; Passariello, R

    2009-06-01

    This study was performed to validate a high-resolution whole-body magnetic resonance angiography (MRA) protocol with parallel imaging and biphasic administration of a single bolus of contrast agent in the preliminary assessment of systemic atherosclerotic burden in patients referred for endovascular procedures. Forty patients referred for endovascular treatment of atherosclerotic disease of the carotid arteries (n=23), peripheral vessels (n=14) or aorta (n=3) on the basis of previous clinical and diagnostic examinations underwent high-resolution whole-body MRA at 1.5 T with 3D spoiled gradient recalled echo (GRE) sequences, featuring parallel imaging acquisition technique with x2 acceleration factor. Sixty-eight surface coil elements and a four-station imaging protocol were employed. Biphasic intravenous administration of a paramagnetic contrast agent [gadolinium benzyloxyproprionic-tetraacetic acid (Gd-BOPTA)] was performed with the following protocol: 10 ml at a speed of 1 ml/s followed by further 10 ml at a speed of 0.5 ml/s. For image analysis, the arterial system was divided into 42 segments for evaluation. The presence or absence of atherosclerotic lesions was evaluated by two observers in consensus; segments were classified as having clinically significant disease (>or=50% stenosis or an aneurysmal dilatation) or no significant disease (<50% stenosis). The presence of stenoocclusive disease, determined at all segments, was compared with findings on digital subtraction angiography (DSA), which were interpreted by a third independent reader. Sensitivity, specificity and concordance of whole-body MRA findings with DSA were calculated, and receiver operating characteristic (ROC) analysis was performed for all vascular territories. A total of 1,680 arterial segments was evaluated; 138 (8.3%) were affected by atherosclerotic alterations. Carotid lesions were confirmed in 23 patients (34 segments), involvement of peripheral vessels in 14 (57 segments) and abdominal

  3. Investigation of the longitudinal relaxation rate of blood after gadobenate dimeglumine administration: sequence optimization, dynamic acquisition, and clinical impact for contrast-enhanced MR angiography of the carotid arteries.

    Science.gov (United States)

    Neira, Cristina; Anzidei, Michele; Napoli, Alessandro; Kirchin, Miles A; Cavallo Marincola, Beatrice; Zaccagna, Fulvio; Catalano, Carlo; Passariello, Roberto; Tedoldi, Fabio

    2011-12-01

    To optimize the image acquisition parameters for improved steady-state (SS) contrast-enhanced magnetic resonance angiography (CE-MRA) of the carotid arteries with gadobenate dimeglumine. An inversion recovery fast low-angle shot (IR-FLASH) sequence for ultrafast determination of the longitudinal relaxation rate R1 was first optimized on phantoms and tested against a routine variable repetition time (TR) spin echo sequence used as reference standard. Different combinations of flip angle (FA, between 6 and 14 degrees) and inversion time (between 134 and 9000 milliseconds) were evaluated to achieve the best trade off between speed and accuracy. The optimized sequence was thereafter used in vivo in 5 subjects to determine the time evolution of blood R1 at 1.5 T after administration of gadobenate dimeglumine at 0.1 mmol/kg bodyweight. An optimal FA for angiographic measurement was thereafter derived from the Ernst equation based on experimental values of R1 previously determined in vivo. Finally, steady-state CE-MRA examinations were performed in 20 subjects to evaluate the improved contrast achieved after optimization of the FA for maximal blood signal enhancement. An ultrafast IR-FLASH sequence with a flip angle of 8 degrees and a properly defined set of inversion time values was shown to give in vitro R1 determinations that were in good agreement with those obtained using a routine, time consuming, variable-TR spin echo sequence. The use of this ultrafast IR-FLASH sequence in vivo allowed the blood signal behavior in the carotid arteries after gadobenate dimeglumine administration to be monitored. Using this sequence, the R1 decreased from 8.7±0.96 s⁻¹ at 30 seconds after injection to 3.8±0.24 s⁻¹ at 10 minutes after injection. Based on these data for R1, the optimal FA for SS CE-MRA was calculated to be 18 degrees for a gradient echo acquisition protocol with TR=7.5 milliseconds, when gadobenate dimeglumine is used. Significantly higher blood signal to noise

  4. Diagnosis of the hypothenar hammer syndrome by high-resolution contrast-enhanced MR angiography

    Energy Technology Data Exchange (ETDEWEB)

    Winterer, J.T.; Ghanem, N.; Schaefer, O.; Lehnhardt, S.; Thuerl, C.; Laubenberger, J. [Department of Diagnostic Radiology, University of Freiburg, Hugstetter Strasse 55, 79106 Freiburg (Germany); Roth, M. [Center of Geriatric Medicine and Gerontology Freiburg, University of Freiburg, Hugstetter Strasse 55, 79106 Freiburg (Germany); Horch, R.E. [Department of Plastic and Hand Surgery, University of Freiburg, Hugstetter Strasse 55, 79106 Freiburg (Germany)

    2002-10-01

    Our objective was to describe the imaging features of hypothenar hammer syndrome using minimally invasive contrast-enhanced MR angiography in comparison with oscillography study. In five patients with hypothenar hammer syndrome Gd-BOPTA-enhanced elliptically reordered 3D pulse sequence MR was compared with oscillography findings and clinical symptoms focusing on angiographic appearance of vessel injury, distribution pattern of hand vasculature and joining branches between the radial and ulnar artery supply. All patients showed segmental occlusion at the site of trauma impact with varying involvement of the superficial palmar arch, common volar digital arteries. Embolic disease was present in 50% of patients and could be clearly identified with MRA. Good correspondence was found between angiographic appearance including the presence of collaterals, clinical symptoms and oscillography. Bilateral comparison was helpful in distinguishing between vessel variants and pathology. Bilateral Gd-BOPTA-enhanced MR angiography is a minimally invasive method to depict clearly the localization and extent of vessel injury in hypothenar hammer syndrome providing valuable information about distribution pattern of hand vasculature and presence of collaterals; however, no flow data can be obtained. (orig.)

  5. Patients with liver FNH and HCC patients with negative AFP: plain and dynamic enhanced MRI and CT findings

    Directory of Open Access Journals (Sweden)

    LI Mingtong

    2015-05-01

    Full Text Available ObjectiveTo investigate plain and dynamic enhanced magnetic resonance imaging (MRI and computed tomography (CT findings in patients with focal nodular hyperplasia (FNH of the liver and hepatocellular carcinoma (HCC patients with negative alpha-fetoprotein (AFP. MethodsA statistical analysis was performed on the clinical data of 124 cases of liver tumor admitted to Beijing Miyun County Hospital from April 2012 to April 2014. ResultsFifty-five of the 74 patients with FNH underwent CT examination, among whom 38 patients received three-phase dynamic enhanced scan and 16 received only plain scan; 62 cases had plain and enhanced MRI with the application of contrast agent Gd-BOPTA in 42 patients. Among the 50 HCC patients with negative AFP, CT examination was performed in 40 and 10 only had plain scan; 46 patients received plain and enhanced MRI with the use of contrast agent Gd-BOPTA in 30. Delayed scan after 1-2 h demonstrated low signal in 30 lesions of the 30 cases. ConclusionFor patients with liver FNH and AFP-negative HCC patients, their plain and dynamic enhanced MRI and CT scan have respective characteristics. A combination of multiple examination methods can significantly improve diagnostic yield of the two diseases.

  6. Comparison of 1.0 M gadobutrol and 0.5 M gadopentate dimeglumine-enhanced MRI in 471 patients with known or suspected renal lesions: Results of a multicenter, single-blind, interindividual, randomized clinical phase III trial

    NARCIS (Netherlands)

    B. Tombach (Bernd); K. Bohndorf (Klaus); W. Brodtrager (Wolfgang); C.D. Claussen (Claus); C. Düber (Christoph); M. Galanski (Michael); E. Grabbe (Eckhardt); G. Gortenuti (Giacomo); M. Kuhn (Michael); W. Gross-Fengels (Walter); R. Hammerstingl (Renate); B. Happel (Brigitte); G. Heinz-Peer (Gertraud); G. Jung (Gregor); T. Kittner (Thomas); R. Lagalla; P. Lengsfeld (Philipp); R. Loose (Reinhard); R.H.G. Oyen (Raymond); P. Pavlica (Pietro); C. Pering (Christiane); R. Pozzi Mucelli (Roberto Silvio); T. Persigehl (Thorsten); P. Reimer (Peter); N.S. Renken (Nomdo); G.M. Richter (Götz); E.J. Rummeny (Ernst); F. Schäfer (Fritz); M. Szczerbo-Trojanowska (Malgorzata); A. Urbanik (Andrzej); T.J. Vogl (Thomas); P. Hajek (Paul)

    2008-01-01

    textabstractThe purpose of this phase III clinical trial was to compare two different extracellular contrast agents, 1.0 M gadobutrol and 0.5 M gadopentate dimeglumine, for magnetic resonance imaging (MRI) in patients with known or suspected focal renal lesions. Using a multicenter, single-blind, in

  7. Severe Adverse Drug Reaction to Gadobenate Dimeglumine

    Directory of Open Access Journals (Sweden)

    Benjamin D. Singer

    2009-01-01

    Full Text Available A 57-year-old man was admitted to our hospital for evaluation and management of stroke in the setting of an atrial septal defect. Shortly after receiving gadobenate dimeglumine for magnetic resonance imaging of the pelvic vessels, he experienced cardiac arrest from which he was resuscitated. His course was complicated by profound distributive shock. The presumed cause was a severe anaphylactic or anaphylactoid reaction to the gadolinium-based compound that he received.

  8. Signal intensity change on unenhanced T1-weighted images in dentate nucleus following gadobenate dimeglumine in patients with and without previous multiple administrations of gadodiamide

    Energy Technology Data Exchange (ETDEWEB)

    Ramalho, Joana [University of North Carolina Hospital, Chapel Hill, NC (United States); Centro Hospitalar de Lisboa Central, Lisbon (Portugal); Semelka, Richard C.; Castillo, Mauricio [University of North Carolina Hospital, Chapel Hill, NC (United States); AlObaidy, Mamdoh [University of North Carolina Hospital, Chapel Hill, NC (United States); King Faisal Specialist Hospital and Research Center, Riyadh (Saudi Arabia); Ramalho, Miguel [University of North Carolina Hospital, Chapel Hill, NC (United States); Hospital Garcia de Orta, Almada (Portugal); Nunes, Renato H. [University of North Carolina Hospital, Chapel Hill, NC (United States); Santa Casa de Misericordia de Sao Paulo, Sao Paulo (Brazil)

    2016-11-15

    To evaluate the impact of previous administration of gadodiamide and neural tissue gadolinium deposition in patients who received gadobenate dimeglumine. Our population included 62 patients who underwent at least three administrations of gadobenate dimeglumine, plus an additional contrast-enhanced last MRI for reference, divided into two groups: group 1, patients who in addition to gadobenate dimeglumine administrations had prior exposure to multiple doses of gadodiamide; group 2, patients without previous exposure to other gadolinium-based contrast agent (GBCAs). Quantitative analysis was performed on the first and last gadobenate dimeglumine MRIs in both groups. Dentate nucleus-to-middle cerebellar peduncle signal intensity ratios (DN/MCP) and relative change (RC) in signal over time were calculated and compared between groups using generalized additive model. Group 1 showed significant increase in baseline and follow-up DN/MCP compared to group 2 (p < 0.0001). The RC DN/MCP showed a non-statistically significant trend towards an increase in patients who underwent previous gadodiamide (p = 0.0735). There is increased T1 signal change over time in patients who underwent gadobenate dimeglumine and had received prior gadodiamide compared to those without known exposure to previous gadodiamide. A potentiating effect from prior gadodiamide on subsequent administered gadobenate dimeglumine may occur. (orig.)

  9. Influence of Different Contrast Agents on Dynamic Contrast-Enhanced MRI Ktrans in Cerebral Metastases: Comparison between 1.0 M Gadobutrol and 0.5M Gadopentetate Dimeglumine%不同对比剂对脑转移瘤MRI动态增强定量参数(Ktrans)的影响

    Institute of Scientific and Technical Information of China (English)

    范兵; 杜华睿; 王霄英; 宛然; 罗晶晶; 张珏

    2014-01-01

    目的 比较不同浓度对比剂(钆布醇与钆喷酸葡胺)对脑转移瘤容积转移常数(Ktrans)的影响.方法 招募10例脑转移瘤患者,签署知情同意书,采用个体内自身随机对照研究,所有患者均接受2次头颅MRI动态增强检查,分别注射2种不同对比剂.采用交叉设计,利用随机表确定注射钆布醇和钆喷酸葡胺的次序,两次检查间隔24~ 48 h.对比剂剂量0.1 mmol/kg体重,注药流率3.0 ml/s,注射对比剂同时启动MR动态增强检查,对直径>5 mm的病灶测量Ktrans值及细胞外血管外间隙(Ve)值.使用SPSS 13.0进行统计学处理,对2种不同对比剂所测Ktrans值及Ve值分别采用方差分析,进一步做Pearson相关性分析,P<0.05认为有统计学差异.结果 2例患者因病灶较小(直径<5 mm)无法测量Krans值而排除,对8例患者共21个病灶进行分析,钆布醇及钆喷酸葡胺所测Ktrans值分别为(0.32±0.19) min-1,(0.35±0.19) min-1 (F=0.315,P>0.05),两者Ve值分别为0.89±0.10,0.88±0.09(F =0.009,P>0.05).两种对比剂所测Ktrans值及Ve值均呈正相关(Ktrans:r =0.712,P<0.001;Ve:r=0.616,P<0.05).结论 使用不同含钆对比剂(钆布醇与钆喷酸葡胺)行MR动态增强扫描,对脑转移瘤病灶所测Ktrans及Ve值具有相关性.%Objective To explore the effect of different Gadolium-based contrast agents (gadobutrol vs.gadopentetate dimeglumine) on the measurement of volume transfer constant (Ktrans) and Ve in dynamic contrast enhanced MRI for cerebral metastases.Methods Ten patients with pathologically-confirmed cerebral metastases were examined by dynamic contrast-enhanced MR imaging with identical scanning protocol for two times.Gadobutrol or gadopentetate dimeglumine were randomly selected for the first study,with dosage of 0.1 mmol gadolium/kg body weight.Twenty-four to 48 hours later,the second study was performed with injection of the other contrast agent.The Ktrans and Ve values of the metastatic foci were

  10. Evaluation of the incidence of nephrogenic systemic fibrosis in patients with moderate renal insufficiency administered gadobenate dimeglumine for MRI

    Energy Technology Data Exchange (ETDEWEB)

    Bryant, B.J. [Department of Radiology, Loma Linda University Medical Center, Loma Linda, California (United States)], E-mail: BJBryant@ahs.llumc.edu; Im, K.; Broome, D.R. [Department of Radiology, Loma Linda University Medical Center, Loma Linda, California (United States)

    2009-07-15

    Aim: To determine the incidence of nephrogenic systemic fibrosis (NSF) in stage 3 chronic kidney disease patients following intravenous exposure to gadobenate dimeglumine. Materials and methods: A prospective study was performed on 168 consecutive patients at a single institution with stage 3 chronic kidney disease who underwent clinically-indicated contrast-enhanced magnetic resonance imaging (MRI) examinations with gadobenate dimeglumine from January 2007 to March 2008. All patients were contacted by phone by investigators 3 months after MRI to verify the presence or absence of NSF signs or symptoms. If signs or symptoms suggestive of NSF developed, dermatologic referral was made and confirmatory skin biopsy performed if indicated. Results: One hundred and eighty contrast-enhanced MRI examinations with gadobenate dimeglumine were performed on the 168 patients. Twenty patients were lost to follow-up, but 160 incidents of contrast medium exposure were followed up for 3-months and 105 incidents were followed up for 6 months. The mean contrast medium dose per weight was 0.093 mmol/kg (range 0.042-0.153 mmol/kg). The mean estimated creatinine clearance was 50.4 ml/min/1.73 m{sup 2} (range from 30-59 ml/min/1.73 m{sup 2}). Ten patients developed skin rashes during the 3-month follow-up period, but none were confirmed to represent NSF (0% prevalence rate). No other signs or symptoms of NSF were reported. Conclusion: Based on this limited study, NSF does not appear to occur in patients with stage 3 chronic kidney disease exposed to intravenous gadobenate dimeglumine for MRI at standard dosing of {approx}0.1 mmol/kg.

  11. MRI of colorectal cancer liver metastases: comparison of orally administered manganese with intravenously administered gadobenate dimeglumine

    Energy Technology Data Exchange (ETDEWEB)

    Brismar, Torkel B.; Kartalis, Nikolaos; Albiin, Nils [Karolinska Institutet, Division of Medical Imaging and Technology, Department of Clinical Science, Intervention and Technology (CLINTEC), Stockholm (Sweden); Kylander, Christian [Karolinska Institutet, Division of Surgery, Department of Clinical Science, Intervention and Technology (CLINTEC), Stockholm (Sweden)

    2012-03-15

    To compare the sensitivity of MRI to detect colorectal cancer liver metastases (CRLM) after ingestion of manganese-based contrast agent (CMC-001) with that of a comprehensive intravenous gadobenate dimeglumine protocol, and to assess the safety and acceptability of oral manganese. 20 patients suspected of having 1-6 CRLM were included prospectively in this randomised cross-over study. Liver MRI was performed with a one-week interval at 1.5 T and included T1-w VIBE and T2-HASTE, before and after administration of 1.6 g CMC-001 or 0.1 mmol/kg gadobenate dimeglumine. The metastasis-to-liver signal intensity (SI) ratio was calculated. Standard of reference was histopathology after surgery, or combination of other imaging studies and/or follow up. Adverse events (AE) and clinicolaboratory tests were monitored. Of 44 metastases, 41 were detected after CMC-001 (93%) and 42 after gadobenate dimeglumine (95%). Fifteen false-positive lesions were found after CMC-001 and 2 after gadobenate dimeglumine. The metastasis-to-liver SI ratio was significantly higher after CMC-001 than after gadobenate dimeglumine (0.51 and 0.21 respectively, P < 0.0001). More AE occurred after manganese compared to gadobenate dimeglumine. CMC-001 is as sensitive as an extensive intravenous gadobenate dimeglumine protocol in detecting CRLM. It was relatively well tolerated but had higher rates of gastrointestinal AE. (orig.)

  12. Quantitative and qualitative comparison of 0.025 mmol/kg gadobenate dimeglumine for abdominal MRI at 1.5 T and 3 T MRI in patients with low estimated glomerular filtration rate

    Energy Technology Data Exchange (ETDEWEB)

    Ramalho, Miguel; AlObaidy, Mamdoh; Busireddy, Kiran K.; Altun, Ersan; Liu, Baodong; Semelka, Richard C., E-mail: richsem@med.unc.edu

    2015-01-15

    Highlights: • Efficacy and adequacy of enhancement using quarter dose gadobenate dimeglumine at 1.5 T was studied in patients with low GFR. • A dose of 0.025 mmol/kg of gadobenate dimeglumine at 1.5 T showed diagnostic enhancement quality in the majority of patients. • There were no significant differences between the qualitative perception of enhancement between 1.5 T and 3 T. • Patients who have renal impairment may still be able to receive GBCAs, while maintaining adequate enhancement at 1.5 T. - Abstract: Purpose: To investigate the efficacy and adequacy of enhancement employing 0.025 mmol/kg of gadobenate dimeglumine at 1.5 Tesla (T), and to compare the extent of enhancement of this dosage between 1.5 T and 3 T systems. Materials and methods: Our final population included 116 consecutive patients who underwent 0.025 mmol/kg gadobenate dimeglumine-enhanced abdominal MRI (78 men and 38 women; age, 64.1 ± 13.6 years). Sixty patients underwent imaging at 1.5 T and 56 patients underwent imaging at 3 T. Abdominal enhancement was evaluated qualitatively and quantitatively. The quality of enhancement was compared using Mann–Whitney U test. The percentage of enhancement of each organ was compared using Student t-test. Results: The mean quality rating of enhancement was at least “good” in all phases of enhancement for both 1.5 T and 3 T. There was a non-significant trend to higher mean ratings at 3 T. The liver showed a 1.3-fold higher arterial-phase percentage of enhancement at 3 T (p = 0.0138). There were no differences between the mean relative enhancement of the pancreas and aorta throughout all phases of enhancement. The percentage of enhancement of the renal cortex was significantly higher at 3 T (p < 0.0001 to p = 0.0293). Conclusion: A dose of 0.025 mmol/kg of gadobenate dimeglumine demonstrates diagnostic enhancement in the majority of patients at 1.5 T, without significant differences on qualitative evaluation compared to 3 T.

  13. Comparative evaluation of gadoteridol versus gadopentetate dimeglumine for contrast-enhanced MRI in a rat brain glioma model at 1.5 and 3.0 T%钆特醇及钆喷替酸葡甲胺在1.5、3.0 TMR下鼠脑胶质瘤模型增强扫描中的应用比较研究

    Institute of Scientific and Technical Information of China (English)

    艾飞; Val M Runge; John N Morelli; Lan.Vu; Jeremy Cannel; Alan T Loynachan; 漆剑频; 李小明

    2010-01-01

    计学意义(t值分别为31.503、5.137,P值均<0.05),而两者CE均值差异无统计学意义(t=2.033,P>0.05).结论 利用鼠脑胶质瘤模型,在1.5及3.0 T MR下注射钆特醇和Gd-DTPA行增强扫描,两者增强效果无明显差异;3.0 T MR下注射钆特醇行增强扫描,效果明显优于在1.5 T条件下使用;3.0 T MR下使用半剂量钆特醇与在1.5 T下使用标准剂量增强效果相仿,同样能取得满意的增强效果.因此,使用钆特醇可在保证增强效果的同时,在一定程度上降低使用MRI对比剂的风险,增加安全性.%Objective To compare gadoteridol and gadopentetate dimeglumine (Gd-DTPA) with respect to lesion enhancement in a rat brain glioma model at 1.5 and 3.0 T. Methods Glioma cells were injected into the brains of 42 male CDF ( Fisher 344) rats through implanted cannula to create Glioma animal model. One week after implantation, all rats were randomly divided in to four groups which included 12,10,10,10 rats. The comparisons included the contrast effect of gadoteridol versus gadopentetate dimeglumine at both 1.5 and 3.0 T. In addition, gadoteridol alone was evaluated by comparing the standard dose at both two field strengths and half dose at 3.0 T to a standard full dose at 1.5 T. Two MRI scans for different contrast agent injections were performed in each animal model with an interval of 24 hours. T1 -weighted images were analyzed pre-contrast and at five time points ( 1, 3, 5, 7 and 9 min) post-contrast with respect to lesion signal-to-noise ratio (SNR), contrast-to-noise ratio (CNR), and contrast enhancement (CE). Student t test was used for statistics. Results The mean SNR, CNR, and CE were respectively 54. 4 ± 3. 2, 17.0 ± 3.3 and 20. 8 ± 3.4 with gadopentetate dimeglumine versus 53.2 ± 3.2, 17.2 ± 3. 1 and 20. 8 ± 3.2 with gadoteridol at 1.5 T at every postcontrast time point ( t = 2. 247, 0. 403, 0. 076, P > 0. 05 ). The mean SNR, CNR, and CE were respectively 94.8 ± 7.1, 38.0 ± 6.0 and 45.0 ± 6.3 with

  14. Does the MRI or MRI contrast medium gadopentetate dimeglumine change the oxidant and antioxidant status in humans?

    Energy Technology Data Exchange (ETDEWEB)

    Olmaz, Refik; Oguz, Ebru Gok; Kiykim, Ahmet; Turgutalp, Kenan [Dept. of Internal Medicine, Div. of Nephrology, School of Medicine, Mersin Univ., Mersin (Turkey)], e-mail: k.turgutalp@hotmail.com; Horoz, M. [Dept. of Internal Medicine, Div. of Nephrology, School of Medicine, Harran Univ., Sanliurfa (Turkey); Ozhan, Onur [Dept. of Internal Medicine, Div. of Endocrinology and Metabolism, School of Medicine, Mersin Univ., Mersin (Turkey); Muslu, Necati [Dept. of Biochemistry, School of Medicine, Mersin Univ., Mersin (Turkey); Sungur, Mehmet [Dept. of Biostatistics, School of Medicine, Mersin Univ., Mersin (Turkey)

    2013-02-15

    Background: It has become evident that gadolinium-based contrast agents (GBCA) may have nephrotoxic potential. Oxidative stress is one of the most important pathways in the pathogenesis of iodinated contrast-induced nephropathy. Purpose: To investigate the effects of static magnetic fields and gadopentetate dimeglumine (Magnevist) on oxidant/antioxidant status via measurement of total antioxidant capacity (TAC), total oxidant status (TOS), and serum malondialdehide (MDA). Material and Methods: Two age- and sex-matched groups of patients not under oxidative stress conditions that underwent magnetic resonance imaging (MRI) were recruited to this study. While contrast-enhanced (Magnevist, 0.2 mmol/kg) MRI was performed in group 1, MRI without GBCA was performed in group 2. Fasting blood glucose, C-reactive protein, serum creatinine, liver enzymes, uric acid, and lipid parameters were examined in all patients. Peripheral venous blood samples in order to determine TAC, TOS, and MDA were collected before and 6, 24, and 72 h after the MRI procedures. The TOS:TAC ratio was used as the oxidative stress index (OSI). Patients were followed up to 72 h. Results: There were no significant changes in serum TAC, TOS, and MDA levels ({Delta}{sub s}erum{sub T}AC, {Delta}{sub s}erum{sub T}OS, and {Delta}{sub M}DA) in either group 6, 24, or 72 h after the procedures (P > 0.05). Furthermore, OSI did not change after the procedures in either group (P > 0.05). Conclusion: Magnetic field and gadopentetate dimeglumine (Magnevist) do not change the oxidant or antioxidant status at a dose of 0.2 mmol/kg.

  15. Comparison of gadoxetate disodium and gadopentetate dimeglumine in dynamic contrast-enhanced liver MRI:an intra-individual comparative study%肝脏MR动态增强扫描:Gd-EOB-DTPA与Gd-DTPA的个体内对照研究

    Institute of Scientific and Technical Information of China (English)

    吴静云; 王可; 郭小超; 王霄英

    2016-01-01

    enhanced liver MR imaging by gadoxetate disodium (Gd-EOB-DTPA)and gadopentetate dimeglumine (Gd-DTPA).Methods:Twenty-five patients suspected of liver metastases from colorectal cancer underwent twice MR examinations on 3 .0T scanner using the contrast agent of Gd-EOB-DTPA (0.05mmol/kg)and Gd-DTPA (0.1mmol/kg)respectively.Pre- and post- dynamic contrast enhanced images were acquired,including arterial phase (AP),portal venous phase (PP),equilibrium phase (EP for Gd-DTPA)/transitional phase (TP for Gd-EOB-DTPA).On images of all phases,signal intensity of abdominal organs (liver and spleen)and vessels (aor-ta,inferior vena cava,portal vein,hepatic vein)were measured,and signal intensity of paravertebral muscle was measured as reference.Relative signal intensity (RS)were calculated and compared between the two groups using the two types of con-trast media.The image features of contrast enhanced images were also subjectively evaluated.Results:There was statistically significant difference in RS of liver on AP images between the two groups (t= 3.006,P= 0.005).There was no statistically significant difference in RS of liver on EP and TP images between the two groups.In Gd-EOB-DTPA group,liver RS on PP images was much higher than that on AP images (t= -3.014,P= 0.006),and on TP images,liver RS was lower than that on PP images but without statistic difference.In Gd-DTPA group,liver RS was much lower on EP images than that on PP images (t= 5.827,P= 0.000).In subjective evaluation,aorta,portal vein and hepatic vein of all patients were hyperintense on EP images in Gd-DTPA group;whereas in Gd-EOB-DTPA group,aorta,portal vein and hepatic vein were mainly hypo-or iso-intense images (84%,92%,92%).Conclusion:In Gd-EOB-DTPA dynamic contrast enhanced MRI,liver parenchyma was continuously enhanced during portal venous phase and transitional phase.The image features in equilibrium phase of Gd-DTPA enhanced scan are quite different from transitional phase of Gd-EOB-DTPA enhanced scan

  16. First-pass and high-resolution steady-state magnetic resonance angiography of the peripheral arteries with gadobenate dimeglumine: an assessment of feasibility and diagnostic performance.

    Science.gov (United States)

    Anzidei, Michele; Napoli, Alessandro; Zaccagna, Fulvio; Cavallo Marincola, Beatrice; Zini, Chiara; Kirchin, Miles A; Catalano, Carlo; Passariello, Roberto

    2011-05-01

    To assess the feasibility of combined first-pass (FP) and steady-state (SS) contrast-enhanced magnetic resonance angiography (MRA) of the peripheral arteries with gadobenate dimeglumine (MultiHance) and to evaluate diagnostic performance relative to digital subtraction angiography (DSA). A total of 35 patients with symptomatic peripheral arterial occlusive disease (PAOD) underwent FP MRA (repetition time [TR]/echo time [TE]/flip angle [FA]/acquisition time [TA] = 3.5/1.2/30°/14s) at 1.5T after intravenous injection of 10 mL of gadobenate dimeglumine. Thereafter, SS imaging of the calf (TR/TE/FA/TA = 7.5/2.3/20°/40-130s) and femoropopliteal (TR/TE/FA/TA = 7.5/2.3/18°/130-240s) regions was performed after a second injection of 5 mL of gadobenate dimeglumine. All patients underwent conventional DSA. Three readers reviewed separate FP and FP+SS MRA datasets for image quality and presence/absence of clinically relevant PAOD. A fourth independent observer evaluated DSA images. The diagnostic performance (sensitivity, specificity, positive and negative predictive values) achieved with each dataset was determined and compared. Inter-reader agreement was assessed using kappa statistics. The image quality of 134 of 140 vascular regions was optimal or adequate on SS MRA. Inter-reader agreement was good to very good for assessments of FP (κ = 0.725) and combined FP+SS images (κ = 0.866). SS images improved diagnostic confidence in 34 (48.6%) femoropoliteal and 46 (65.7%) crural regions and altered final diagnosis in 8 (11.4%) and 10 (14.3%) regions, respectively. Global diagnostic accuracy increased from 92.9% on FP images to 95.9% on FP+SS images, with significant (P = 0.0384) improvement in the crural region. SS MRA of the peripheral arteries is feasible with gadobenate dimeglumine and potentially improves diagnostic performance in patients with symptomatic PAOD.

  17. Cardiac MRI to investigate myocardial scar and coronary venous anatomy using a slow infusion of dimeglumine gadobenate in patients undergoing assessment for cardiac resynchronization therapy.

    Science.gov (United States)

    Duckett, Simon G; Chiribiri, Amedeo; Ginks, Matthew R; Sinclair, Stephen; Knowles, Benjamin R; Botnar, Rene; Carr-White, Gerry S; Rinaldi, Christopher A; Nagel, Eike; Razavi, Reza; Schaeffter, Tobias

    2011-01-01

    To evaluate a cardiac MR (CMR) examination with slow infusion of a high-relaxivity contrast agent to visualize coronary venous anatomy (CVA) and myocardial scar in heart failure patients awaiting cardiac resynchronization therapy (CRT). Fourteen patients awaiting CRT (seven ischemic cardiomyopathy (ICM) and seven non-ICM) and two with normal LV function underwent CMR on a 1.5 Tesla (T) MR scanner. Dimeglumine-gadobenate was slowly infused. Bolus arrival in the LV was measured by a dynamic electrocardiogram (ECG) -triggered inversion recovery (IR) scan subsequent to starting an ECG-triggered respiratory-navigated three-dimensional (3D) SSFP MR scan with IR preparation to acquire systolic whole-heart anatomy for vein visualization. Delayed contrast-enhanced MR scan was performed to assess myocardial scar. CVA obtained by CMR was compared with X-ray venography in 11 patients. CVA and scar were segmented and registered for visual inspection. For all subjects, there was excellent visualization of the CVA. All ICM and one non-ICM patient showed scar. There was excellent correlation between veins seen by CMR and venography. We have demonstrated that slow infusion protocol of dimeglumine-gadobenate can be used to assess both CVA and myocardial scar in a single MR examination. Furthermore, an image overlay technique has been used to show the relationship of scar to the CVA. Copyright © 2010 Wiley-Liss, Inc.

  18. Quantitative and qualitative comparison of 0.025 mmol/kg gadobenate dimeglumine for abdominal MRI at 1.5T and 3T MRI in patients with low estimated glomerular filtration rate.

    Science.gov (United States)

    Ramalho, Miguel; AlObaidy, Mamdoh; Busireddy, Kiran K; Altun, Ersan; Liu, Baodong; Semelka, Richard C

    2015-01-01

    To investigate the efficacy and adequacy of enhancement employing 0.025 mmol/kg of gadobenate dimeglumine at 1.5 Tesla (T), and to compare the extent of enhancement of this dosage between 1.5T and 3T systems. Our final population included 116 consecutive patients who underwent 0.025 mmol/kg gadobenate dimeglumine-enhanced abdominal MRI (78 men and 38 women; age, 64.1 ± 13.6 years). Sixty patients underwent imaging at 1.5T and 56 patients underwent imaging at 3T. Abdominal enhancement was evaluated qualitatively and quantitatively. The quality of enhancement was compared using Mann-Whitney U test. The percentage of enhancement of each organ was compared using Student t-test. The mean quality rating of enhancement was at least "good" in all phases of enhancement for both 1.5T and 3T. There was a non-significant trend to higher mean ratings at 3T. The liver showed a 1.3-fold higher arterial-phase percentage of enhancement at 3T (p=0.0138). There were no differences between the mean relative enhancement of the pancreas and aorta throughout all phases of enhancement. The percentage of enhancement of the renal cortex was significantly higher at 3T (pqualitative evaluation compared to 3T. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

  19. High-resolution steady state magnetic resonance angiography of the carotid arteries: are intravascular agents necessary?: feasibility and preliminary experience with gadobenate dimeglumine.

    Science.gov (United States)

    Anzidei, Michele; Napoli, Alessandro; Marincola, Beatrice Cavallo; Kirchin, Miles A; Neira, Cristina; Geiger, Daniel; Zaccagna, Fulvio; Catalano, Carlo; Passariello, Roberto

    2009-12-01

    To prospectively evaluate the potential of gadobenate dimeglumine for high-resolution steady-state (SS) contrast-enhanced magnetic resonance angiography (CE-MRA) of the carotid arteries as an adjunct to conventional first-pass (FP) MRA, with computed tomography angiography (CTA) and digital subtraction angiography (DSA) as reference. Institutional ethics committee approval and written informed consent were obtained. Forty consecutive patients underwent conventional FP MRA with 15 mL gadobenate dimeglumine, using a conventional 3D FLASH sequence (14 sec acquisition time). Immediately afterward, SS images were obtained using a high resolution coronal 3D FLASH sequence (240 sec acquisition time). All patients also underwent CTA and conventional DSA within 8 +/- 3 days. Three experienced radiologists assessed FP and SS image quality and calculated sensitivity, specificity, accuracy, and predictive values for stenosis grade and length, plaque morphology, and tandem lesions using DSA as reference. Detected stenoses were quantified and compared (Spearman rank correlation coefficient, [R(s)]; McNemar test) with DSA and CTA findings. Inter-read variability was assessed using kappa (kappa) statistics. The impact of SS acquisitions on diagnostic confidence and patient management was assessed. MRA FP and SS image quality was excellent in 63 (78.8%) and 46 (57.5%) vessels, adequate in 11 (13.8%) and 20 (25.0%) vessels, and poor in 6 (7.5%) and 14 (17.5%) vessels, respectively. Area under the curve analysis revealed no significant differences between MRA FP, MRA FP + SS, and CTA for the grading of stenoses (P = 0.838; accuracy values of 97.4%, 97.4%, and 98.7%, respectively). Greater accuracy (P < 0.001) was noted for FP + SS images over FP images alone for the assessment of plaque morphology (96.1% for FP + SS images vs. 83.3% for FP). Increased diagnostic confidence was noted for 49 (61.3%) vessels because of additional SS images whereas an impact on final diagnosis was noted

  20. Objective evaluation of acute adverse events and image quality of gadolinium-based contrast agents (gadobutrol and gadobenate dimeglumine) by blinded evaluation. Pilot study.

    Science.gov (United States)

    Semelka, Richard C; Hernandes, Mateus de A; Stallings, Clifton G; Castillo, Mauricio

    2013-01-01

    The purpose was to objectively evaluate a recently FDA-approved gadolinium-based contrast agent (GBCA) in comparison to our standard GBCA for acute adverse events and image quality by blinded evaluation. Evaluation was made of a recently FDA-approved GBCA, gadobutrol (Gadavist; Bayer), in comparison to our standard GBCA, gadobenate dimeglumine (MultiHance; Bracco), in an IRB- and HIPAA-compliant study. Both the imaging technologist and patient were not aware of the brand of the GBCA used. A total of 59 magnetic resonance studies were evaluated (59 patients, 31 men, 28 women, age range of 5-85 years, mean age of 52 years). Twenty-nine studies were performed with gadobutrol (22 abdominal and 7 brain studies), and 30 studies were performed with gadobenate dimeglumine (22 abdominal and 8 brain studies). Assessment was made of acute adverse events focusing on objective observations of vomiting, hives, and moderate and severe reactions. Adequacy of enhancement was rated as poor, fair and good by one of two experienced radiologists who were blinded to the type of agent evaluated. No patient experienced acute adverse events with either agent. The target minor adverse events of vomiting or hives, and moderate and severe reactions were not observed in any patient. Adequacy of enhancement was rated as good for both agents in all patients. Objective, blinded evaluation is feasible and readily performable for the evaluation of GBCAs. This proof-of-concept study showed that both GBCAs evaluated exhibited consistent good image quality and no noteworthy adverse events. Copyright © 2013 Elsevier Inc. All rights reserved.

  1. Contrast-enhanced MR angiography: does a higher relaxivity MR contrast agent permit a reduction of the dose administered for routine vascular imaging applications?

    Science.gov (United States)

    Xing, Xiaoying; Zeng, Xiangzhu; Li, Xuan; Zhao, Qiang; Kirchin, Miles A; Pirovano, Gianpaolo; Wang, Xiaoying; Li, Yuan; Iezzi, Roberto; De Cobelli, Francesco

    2015-02-01

    The authors prospectively compared single dose (0.1 mmol/kg bodyweight) gadobenate dimeglumine with double dose (0.2 mmol/kg bodyweight) gadopentetate dimeglumine for contrast-enhanced magnetic resonance angiography (CE-MRA) in patients with suspected or known steno-occlusive disease of the carotid, renal or peripheral vasculature using an intra-individual crossover study design. Twenty-eight patients with suspected or known steno-occlusive disease of the carotid (n = 16), renal (n = 5) or peripheral arteries (n = 7) were randomised to receive either 0.1 mmol/kg gadobenate dimeglumine or 0.2 mmol/kg gadopentetate dimeglumine for a first CE-MRA procedure. After 3-5 days all patients underwent a second identical CE-MRA procedure with the other contrast agent. Three blinded readers assessed images for vessel anatomical delineation, disease detection/exclusion, and global preference. Diagnostic performance for detection of ≥51 % stenosis was determined for 20/28 patients who also underwent digital subtraction angiography (DSA). Non-inferiority was assessed using the Wilcoxon signed rank, McNemar and Wald tests. Quantitative (signal-to-noise and contrast-to-noise ratio) enhancement based on 3D maximum intensity projection reconstructions was compared. No differences were noted for any qualitative parameter. Equivalence was reported for all diagnostic preference end-points. Superiority for gadobenate dimeglumine was reported by all readers for sensitivity for disease detection (80.8-86.5 vs. 75.0-82.7 %). Quantitative enhancement was similar for single dose gadobenate dimeglumine and double dose gadopentetate dimeglumine. Under identical examination conditions a single 0.1 mmol/kg body weight dose of gadobenate dimeglumine can fully replace a double 0.2 mmol/kg body weight dose of gadopentetate dimeglumine for routine CE-MRA procedures.

  2. 肝脏局灶性结节性增生和甲胎蛋白阴性肝细胞癌患者的影像学特点分析%Patients with liver FNH and HCC patients with negative AFP:plain and dynamic enhanced MRI and CT findings

    Institute of Scientific and Technical Information of China (English)

    李明通

    2015-01-01

    目的:探讨肝脏局灶性结节性增生(FNH)和甲胎蛋白(AFP)阴性肝细胞癌(HCC)患者的 MRI 和 CT 平扫及动态增强表现。方法回顾性分析2012年4月-2014年4月北京市密云县医院收治的124例肝脏肿瘤患者的临床资料。结果74例 FNH患者中,54例患者接受 CT 检查,其中38例患者接受三期动态增强扫描,16例患者仅接受平扫;62例患者接受 MRI 检查,均接受平扫及增强扫描,其中应用钆贝葡胺(Gd -BOPTA)造影剂42例。50例 AFP 阴性 HCC 患者中,40例患者接受 CT 检查,其中10例患者只接受平扫;46例患者接受 MRI 平扫及增强扫描,其中采用 Gd -BOPTA 造影剂30例,30例30个病灶中延迟1~2 h 扫描均呈低信号。结论FNH 和 AFP 阴性 HCC 患者的 MRI 和 CT 平扫及动态增强表现各具特点,多种检查方法联合应用能够促进二者诊断率的显著提升。%Objective To investigate plain and dynamic enhanced magnetic resonance imaging (MRI)and computed tomography (CT) findings in patients with focal nodular hyperplasia (FNH)of the liver and hepatocellular carcinoma (HCC)patients with negative alpha -fe-toprotein (AFP).Methods A statistical analysis was performed on the clinical data of 124 cases of liver tumor admitted to Beijing Miyun County Hospital from April 2012 to April 2014.Results Fifty -five of the 74 patients with FNH underwent CT examination,among whom 38 patients received three -phase dynamic enhanced scan and 16 received only plain scan;62 cases had plain and enhanced MRI with the application of contrast agent Gd -BOPTA in 42 patients.Among the 50 HCC patients with negative AFP,CT examination was performed in 40 and 10 only had plain scan;46 patients received plain and enhanced MRI with the use of contrast agent Gd -BOPTA in 30.Delayed scan after 1 -2 h demonstrated low signal in 30 lesions of the 30 cases.Conclusion For patients with liver FNH and AFP -negative HCC pa

  3. Estimating kinetic parameters from dynamic contrast-enhanced T(1)-weighted MRI of a diffusable tracer: standardized quantities and symbols

    DEFF Research Database (Denmark)

    Tofts, P.S.; Brix, G; Buckley, D.L.

    1999-01-01

    We describe a standard set of quantity names and symbols related to the estimation of kinetic parameters from dynamic contrast-enhanced T(1)-weighted magnetic resonance imaging data, using diffusable agents such as gadopentetate dimeglumine (Gd-DTPA). These include a) the volume transfer constant K...

  4. Detection of biliary and vascular anatomy in living liver donors: Value of gadobenate dimeglumine enhanced MR and MDCT angiography

    Energy Technology Data Exchange (ETDEWEB)

    Artioli, Diana, E-mail: diansadiana@gmail.com [Ospedale Niguarda Ca' Granda, Piazza Ospedale Maggiore 3, 20162 Milano (Italy); Tagliabue, Marianna; Aseni, Paolo; Sironi, Sandro; Vanzulli, Angelo [Ospedale Niguarda Ca' Granda, Piazza Ospedale Maggiore 3, 20162 Milano (Italy)

    2010-11-15

    Objective: To evaluate the performance of magnetic resonance (MR) and multidetector computed tomography (MDCT) in the assessment of living donor's vascular and biliary anatomy, having surgical findings as reference standard. Methods: Thirty-two living liver donors underwent MR cholangiography (1.5-T; standard cholangiography pulse sequences and delayed acquisitions after administration of biliary contrast agent) for biliary anatomy evaluation. MDCT (16-row multidetector scanner, multiphase protocol, 3 mm slice thickness) was also performed in all cases for the assessment of vascular anatomy before transplantation. Hepatic veins (<4 mm in diameter) were not considered. MR and MDCT images interpretation was performed by two reviewers by consensus, based on source axial images, multiplanar reformats, and three-dimensional (3D) postprocessing images. Surgical intraoperative findings were used as standard of reference. Results: At surgery, 17 biliary anomalies, 3 portal anomalies, 32 venous and 8 arterial variants were found in the 32 patients. MR correctly identified 15/17 biliary anomalies, with a sensitivity of 88% and a specificity of 93%. MDCT correctly identified 8/8 arterial, 3/3 portal and 29/32 venous variants, with a sensitivity of 100% and 91%, respectively, and a specificity of 100%. Conclusions: MR and MDCT proved to be efficient in evaluating living liver donor's biliary and vascular anatomy.

  5. Contrast-enhanced specific absorption rate-efficient 3D cardiac cine with respiratory-triggered radiofrequency gating.

    Science.gov (United States)

    Henningsson, Markus; Chan, Raymond H; Goddu, Beth; Goepfert, Lois A; Razavi, Reza; Botnar, Rene M; Schaeffter, Tobias; Nezafat, Reza

    2013-04-01

    To investigate the use of radiofrequency (RF) gating in conjunction with a paramagnetic contrast agent to reduce the specific absorption rate (SAR) and increase the blood-myocardium contrast in balanced steady-state free precession (bSSFP) 3D cardiac cine. RF gating was implemented by synchronizing the RF-excitation with an external respiratory sensor (bellows), which could additionally be used for respiratory gating. For reference, respiratory-gated 3D cine images were acquired without RF gating. Free-breathing 3D cine images were acquired in eight healthy subjects before and after contrast injection (Gd-BOPTA) and compared to breath-hold 2D cine. RF-gated 3D cine reduced the SAR by nearly 40% without introducing significant artifacts while providing left ventricle (LV) measurements similar to those obtained with 2D cine. The contrast-to-noise ratio (CNR) was significantly higher for 3D cine compared to 2D cine, both before and after contrast injection; however, no statistically significant CNR increase was observed for the postcontrast 3D cine compared to the precontrast acquisitions. Respiratory-triggered RF gating significantly reduces SAR in 3D cine acquisitions, which may enable a more widespread clinical use of 3D cine. Furthermore, CNR of 3D bSSFP cine is higher than of 2D and administration of Gd-BOPTA does not improve the CNR of 3D cine. Copyright © 2012 Wiley Periodicals, Inc.

  6. Contrast ultrasound in hepatocellular carcinoma at a tertiary liver center: First Indian experience.

    Science.gov (United States)

    Laroia, Shalini Thapar; Bawa, Simranjeet Singh; Jain, Deepak; Mukund, Amar; Sarin, Shiv

    2013-06-28

    To assess the role of contrast enhanced ultrasonography in evaluation of hepatocellular carcinoma (HCC) at the first Indian tertiary liver center. Retrospective analysis of contrast enhanced ultrasound (CEUS) examinations over 24 mo for diagnosis, surveillance, characterization and follow up of 50 patients in the context of HCC was performed. The source and indication of referrals, change in referral rate, accuracy and usefulness of CEUS in a tertiary liver center equipped with a 64 slice dual energy computer tomography (CT) and 3 tesla magnetic resonance imaging (MRI) were studied. Sonovue (BR1, Bracco, Italy, a second generation contrast agent) was used for contrast US studies. Contrast enhanced CT/MRI or both were performed in all patients. The findings were taken as a baseline reference and correlation was done with respect to contrast US. Contrast enhanced MRI was performed using hepatocyte specific gadobenate dimeglumine (Gd-BOPTA). Iomeron (400 mg; w/v) was used for dynamic CT examinations. About 20 (40%) of the examinations were referred from clinicians for characterization of a mass from previous imaging. About 15 (30%) were performed for surveillance in chronic liver disease; 5 (10%) examinations were performed for monitoring lesions after radiofrequency ablation (RFA); 3 (6%) were post trans-arterial chemo-embolization (TACE) assessments and 3 (6%) were patients with h/o iodinated contrast allergy. About 2 (4%) were performed on hemodynamically unstable patients in the intensive care with raised alpha fetoprotein and 2 (4%) patients were claustrophobic. The number of patients referred from clinicians steadily increased from 12 in the first 12 mo of the study to 38 in the last 12 mo. CEUS was able to diagnose 88% of positive cases of HCC as per reference standards. In the surveillance group, specificity was 53.3% vs 100% by CT/MRI. Post RFA and TACE specificity of lesion characterization by CEUS was 100% in single/large mass assessment, similar to CT

  7. Contrast-enhanced 3D MR venography of thoracic central veins: preliminary experience; Kontrastmittelverstaerkte 3D-MR-Venographie der oberen Thoraxapertur: erste Erfahrungen

    Energy Technology Data Exchange (ETDEWEB)

    Goyen, M.; Barkhausen, J.; Kuehl, H.; Goehde, S.C.; Bosk, S.; Debatin, J.F.; Ruehm, S.G. [Universitaetsklinikum Essen (Germany). Zentralinst. fuer Roentgendiagnostik; Kroeger, K. [Universitaetsklinikum Essen (Germany). Klinik und Poliklinik fuer Angiologie

    2001-04-01

    koronarer Schnittfuehrung mit einer Akquisitionszeit von 3,74 s (TR 1,6 ms, TE 0,6 ms, Flipwinkel 15 , Slabdicke 110 mm, effektive Schichtdicke 2,75 mm, 40 Partitionen, FOV 360 mm, Matrix 140x256) eingesetzt. Ohne Testbolus wurden 20 ml Gd-BOPTA (MultiHance {sup trademark}, Bracco, Italien) gefolgt von 20 ml NaCl mit einer Flussrate von 4 ml/s injiziert (MEDRAD {sup trademark}, Pittsburgh, USA). 10 Sekunden nach Beginn der KM-Injektion wurden 6 3D-Datensaetze in unmittelbarer Folge waehrend einer einzigen Atemanhalteperiode (24 s) akquiriert. Ergebnisse: Die kontrastmittelverstaerkte MR-Venographie lieferte bei allen Patienten diagnostisch verwertbare Bildsequenzen. Im Vergleich zur Duplexsonographie wurden Thrombosen, postthrombotische Veraenderungen sowie funktionelle Abflussstoerungen zuverlaessig erkannt. Schlussfolgerung: Das vorgestellte Verfahren erlaubt die diagnostische Darstellung der Venen der oberen Thoraxapertur. Die dynamische Akquisition von 3D-Datensaetzen ermoeglicht die Darstellung der arteriellen und venoesen Gefaesssysteme in den unterschiedlichen Kontrastmitteldurchflutungsphasen von frueh-arteriell bis spaet-venoes. Der repetitive Einsatz der Technik mit unterschiedlichen Armpositionen ermoeglicht ferner eine Darstellung funktioneller Gefaessstenosen. (orig.)

  8. Comparison of the iron oxide-based blood-pool contrast medium VSOP-C184 with gadopentetate dimeglumine for first-pass magnetic resonance angiography of the aorta and renal arteries in pigs.

    Science.gov (United States)

    Schnorr, Jörg; Wagner, Susanne; Abramjuk, Claudia; Wojner, Ines; Schink, Tania; Kroencke, Thomas J; Schellenberger, Eyk; Hamm, Bernd; Pilgrimm, Herbert; Taupitz, Matthias

    2004-09-01

    VSOP-C184 at a dose of 0.045 mmol Fe/kg has been shown to be an efficient blood pool contrast medium for equilibrium magnetic resonance angiography (MRA) that can be administered as a bolus. The present study was performed to determine whether VSOP-C184 is also suitable for first-pass MRA. Fifteen MRA examinations at 1.5 T were performed in minipigs using a fast 3D fast low-angle shot (FLASH) sequence (repetition time = 4.5 ms, echo time = 1.7 ms, excitation angle = 25 degrees, matrix 256, body phased-array coil). The citrate-stabilized iron oxide preparation VSOP-C184 was investigated (total particle diameter: 7.0 +/- 0.15 nm; core size: 4 nm) and compared with gadopentetate dimeglumine (Gd-DTPA). The following doses were tested: VSOP-C184: 0.015, 0.025, and 0.035 mmol Fe/kg; Gd-DTPA: 0.1 and 0.2 mmol Gd/kg; n = 3 examinations/dose. Data were analyzed quantitatively (signal enhancement (ENH) and vessel edge definition (VED)) and qualitatively. First-pass MRA using the 3 doses of VSOP-C184 yielded the following ENH: aorta: 9.4 +/- 2.6; 12.31 +/- 1.2; 16.53 +/- 1.7; renal arteries: 7.6 +/- 2.2; 9.9 +/- 1.0; 13.2 +/- 0.5. The values for the 2 doses of Gd-DTPA were aorta: 12.9 +/- 1.0; 16.8 +/- 2.2; renal arteries: 11.2 +/- 1.23; 11.3 +/- 1.7. VED for the 3 doses of VSOP-C184 was aorta: 106.3 +/- 31.0; 135.3 +/- 58.8; 141.3 +/- 71.0; renal arteries: 102.2 +/- 24.3; 146.8 +/- 63.0; 126.9 +/- 37.6 and for the 2 doses of Gd-DTPA, aorta: 157.2 +/- 47.8; 164.2 +/- 36.8; renal arteries: 165.9 +/- 30.4; 170.3 +/- 38.2 respectively. The differences between VSOP-C184 and Gd-DTPA are clinically not relevant and statistically not significant (p > or = .05). Qualitative evaluation of image quality, contrast, and delineation of vessels showed the results obtained with VSOP-C184 at doses of 0.025 and 0.035 mmol Fe/kg to be similar to those of Gd-DTPA at 0.1 and 0.2 mmol Gd/kg. VSOP-C184 is suitable for first-pass MRA at doses of 0.025 and 0.035 mmol Fe/kg and thus, in addition to

  9. Is enhanced MRI helpful in brainstem infarction?

    Energy Technology Data Exchange (ETDEWEB)

    Jeong, Y. M.; Shin, G. H.; Choi, W. S. [Kyung Hee University Hospital, Seoul (Korea, Republic of)

    1994-12-15

    To determine the role of MR contrast enhancement in evaluating time course of brainstem infarction. MR imaging with IV administration of gadopentetate dimeglumine was retrospectively reviewed in 43 patients with clinically and radiologically documented brainstem infarctions. The pattern of infarction was classified into spotty and patchy. Presence of parenchymal enhancement in infarction was evaluated. By location, there were 34 pontine, 3 midbrain, 6 medullary infarctions. The age of the infarctions ranged from 1 day to 9 months, with 5 patients scanned within 3 days and 10 scanned within 2 weeks of clinical ictus. Abnormalities on T2-weighted images were encountered in every case, with spotty pattern in 14 cases and patchy pattern in 29 cases. Parenchymal contrast enhancement was seen in 9 cases(20%), primarily occurring between days 8 and 20. MR contrast enhancement in brainstem infarction was infrequent that it may not be useful in the estimation of the age of infarction.

  10. 兔脾内肝细胞移植的磁共振示踪研究%Magnetic resonance tracking of intrasplenic hepatocyte transplantation in rabbits

    Institute of Scientific and Technical Information of China (English)

    刘飒华; 何爱清; 刘丽华; 李灼日

    2013-01-01

    decreased from 1d to 32d group. Liver cells was not found in the control group in the spleen. Conslusion Magnetic resonance imaging can be used in tracing of hepatocytes transplantation after Gd-BOPTA enhanced delayed phase.

  11. Dynamic gadolinium-enhanced MR imaging in active and inactive immunoinflammatory gonarthritis

    DEFF Research Database (Denmark)

    Østergaard, Mikkel; Lorenzen, I; Henriksen, O

    1994-01-01

    examined 16 clinically active (CAG), 7 clinically inactive (CIG) and 4 healthy knees. The synovium of a preselected slice was outlined. Its area and relative signal intensity increase after gadopentetate dimeglumine on T1-SE and FLASH (at each time t) were calculated. The CAG knees showed a mean signal...... intensity increase on early dynamic FLASH images higher by far than the CIG knees, while no significant difference was found on spin-echo images obtained 5 to 15 min after contrast injection. The early signal enhancement probably reflects the perfusion and capillary permeability of the synovium. The area...

  12. Dynamic gadolinium-enhanced MR imaging in active and inactive immunoinflammatory gonarthritis

    DEFF Research Database (Denmark)

    Østergaard, Mikkel; Lorenzen, I; Henriksen, O

    1994-01-01

    examined 16 clinically active (CAG), 7 clinically inactive (CIG) and 4 healthy knees. The synovium of a preselected slice was outlined. Its area and relative signal intensity increase after gadopentetate dimeglumine on T1-SE and FLASH (at each time t) were calculated. The CAG knees showed a mean signal...... intensity increase on early dynamic FLASH images higher by far than the CIG knees, while no significant difference was found on spin-echo images obtained 5 to 15 min after contrast injection. The early signal enhancement probably reflects the perfusion and capillary permeability of the synovium. The area...

  13. Contrast-Enhanced MR Angiography (CEMRA) in Peripheral Arterial Occlusive Disease (PAOD): conventional moving table technique versus hybrid technique; Kontrastverstaerkte MR-Angiographie (CEMRA) bei peripherer AVK (pAVK): konventionelle Tischverschiebetechnik versus Hybrid-Technik

    Energy Technology Data Exchange (ETDEWEB)

    Kalle, T. von; Gerlach, A.; Hatopp, A.; Klinger, S.; Prodehl, P.; Arlat, I.P. [Katharinenhospital, Stuttgart (Germany). Radiologisches Inst.

    2004-01-01

    Patients and Methods: 80 patients (males n = 60, females n = 20, median age = 70 years, diabetics n = 27) with PAOD were examined with a 1,5T system (40 mT/m) using a dedicated phased array peripheral vascular coil. Protocol A consisted of a single injection of Gd-BOPTA with consecutive craniocaudal image acquisition and protocol B of two injections, with the first injection of Gd-BOPTA followed by image acquisition of the popliteocrural and pedal segments and the second injection followed by acquiring the aortoiliac and femoral segments (hybrid technique). The evaluation of the arterial system was directed to the iliac, femoral, popliteocrural and pedal arteries. Results: The visualization of the entire aortopedal vascular system was of diagnostically good or satisfactory quality in 16 of 40 patients using protocol A and in 29 of 40 patients using protocol B (iliac 40 vs. 37, femoral 40 vs. 40, popliteocrural 35 vs. 37, pedal 16 vs. 29); without the pedal station the number increased to 35 of 40 patients for both protocols. The reason of diagnostic limitations was an arteriovenous overlap in 24 of 80 cases, with 19 of 40 cases for protocol A and 5 of 40 for protocol B, located exclusively in the cruropedal region. Conclusion: Moving table hybrid CEMRA is superior to conventional technique in craniocaudal direction by producing less venous overlap of arteries and is especially more suitable for the diagnostic evaluation of the cruropedal region. (orig.) [German] Patienten und Methodik: Untersucht wurden 80 Patienten (maennl. n = 60, weibl. n = 20, mittl. Alter 70 J., Diabetiker n = 27) mit pAVK an einem 1,5-Tesla-Geraet (40 mT/m) mit dedizierter Phased-Array-Oberflaechen-Gefaessspule. Protokoll A beinhaltete eine Kontrastmittel-Injektion (Gd-BOPTA) mit konsekutiver kraniokaudaler Bildakquisition. In Protokoll B erfolgte die Akquisition zunaechst der Unterschenkel- und Fussetage mittels einer ersten, anschliessend der Abdomen-Becken- und Oberschenkeletage mittels

  14. Enhancement of abdominal structures on MRI at 1.5 and 3 T: a retrospective intraindividual crossover comparison

    Energy Technology Data Exchange (ETDEWEB)

    AlObaidy, Mamdoh [King Faisal Specialist Hospital and Research Center, Department of Radiology, Riyadh (Saudi Arabia); University of North Carolina at Chapel Hill, Department of Radiology, Chapel Hill, NC (United States); Ramalho, Miguel; Velloni, Fernanda; Matos, Antonio P.; Herman, Kevin; Semelka, Richard C. [University of North Carolina at Chapel Hill, Department of Radiology, Chapel Hill, NC (United States)

    2017-04-15

    To quantitatively compare the extent of enhancement of abdominal structures on MRI in an intraindividual fashion at 1.5 and 3 T. HIPAA-compliant, retrospective, longitudinal, intraindividual, crossover study, with waived informed consent, of consecutive individuals scanned at both 1.5 and 3 T closed-bore magnets using gadobenate dimeglumine during different phases of enhancement at tightly controlled arterial phase timing. Quantitative ROI measurements and qualitative sub-phase arterial phase assignments were independently performed by two radiologists. Qualitative discrepancies were resolved by a senior radiologist. Final population included 60 patients [41 female and 19 male; age, 49.35 ± 18.31 years (range 16-81); weight, 78.88 ± 20.3 kg (range 44.5-136)]. Similar enhancement peak patterns were noted at both field strengths. Interobserver agreement of quantitative evaluations was substantial. Significantly higher amplitudes of enhancement peaks were noted for all abdominal solid organs during all phases at 3 T, except for the pancreas (p = 0.17-0.30). Significantly higher amplitudes of enhancement peaks of the abdominal aorta at 1.5 T were noted. Similar peak patterns of enhancement for abdominal structures were observed at 1.5 and 3 T, with solid abdominal organs showing a higher percentage enhancement at 3 T, while unexpectedly higher aortic higher percentage enhancement was observed at 1.5 T. (orig.)

  15. Contrast-enhanced magnetic resonance imaging for the detection of acute haemorrhagic necrotizing pancreatitis

    Energy Technology Data Exchange (ETDEWEB)

    Piironen, A. [Department of Radiology, Helsinki University Central Hospital, Helsinki (Finland); Kivisaari, R. [Department of Radiology, Helsinki University Central Hospital, Helsinki (Finland); Pitkaeranta, P. [Department of Radiology, Helsinki University Central Hospital, Helsinki (Finland); Poutanen, V.P. [Department of Radiology, Helsinki University Central Hospital, Helsinki (Finland); Laippala, P. [School of Public Health/Biometry Unit, Tampere University, Tampere (Finland); Laurila, P. [Department of Pathology, Helsinki Univ. (Finland); Kivisaari, L. [Department of Radiology, Helsinki University Central Hospital, Helsinki (Finland)

    1997-02-01

    Eleven piglets with haemorrhagic necrotizing pancreatitis and nine piglets with oedematous pancreatitis were imaged using a multi-breath-hold TurboFLASH (TR 6.5 ms, TE 3 ms, TI 300 ms, flip angle 8 , three slices) pre-excited T1-weighted sequence with an IV bolus injection of gadopentetate dimeglumine (Gd-DTPA, 0.3 mmol/kg) as a contrast agent to show dynamic contrast enhancement of the pancreas by MRI. All piglets were imaged according to the same protocol before inducing the disease. Following the IV Gd-DTPA bolus, time-enhancement curve of the pancreas during haemorrhagic necrotizing pancreatitis was significantly lower than during oedematous pancreatitis. The enhancement curves for the healthy piglets and piglets with oedematous pancreatitis did not differ significantly. Each piglet served as its own control. Because the results of this initial study are similar to those obtained with contrast-enhanced CT, we conclude that our results may encourage further clinical trials, and contrast-enhanced dynamic MRI may be an alternative to the established method of CT for diagnosing acute haemorrhagic necrotizing pancreatitis. (orig.). With 3 figs.

  16. High-relaxivity contrast-enhanced magnetic resonance neuroimaging: a review

    Energy Technology Data Exchange (ETDEWEB)

    Giesel, Frederik L. [German Cancer Research Centre (DKFZ), Department of Radiology E010, Heidelberg (Germany); University of Heidelberg, Nuclear Medicine, Heidelberg (Germany); Mehndiratta, Amit [German Cancer Research Centre (DKFZ), Department of Radiology E010, Heidelberg (Germany); Harvard Medical School, Department of Radiology, Massachusetts General Hospital, Boston, MA (United States); Essig, Marco [German Cancer Research Centre (DKFZ), Department of Radiology E010, Heidelberg (Germany)

    2010-10-15

    Evaluation of brain lesions using magnetic resonance imaging (MRI) provides information that is critical for accurate diagnosis, prognosis, therapeutic intervention and monitoring response. Conventional contrast-enhanced MR neuroimaging using gadolinium (Gd) contrast agents primarily depicts disruption of the blood-brain barrier, demonstrating location and extent of disease, and also the morphological details at the lesion site. However, conventional imaging results do not always accurately predict tumour aggressiveness. Advanced functional MRI techniques such as dynamic contrast-enhanced perfusion-weighted imaging utilise contrast agents to convey physiological information regarding the haemodynamics and neoangiogenic status of the lesion that is often complementary to anatomical information obtained through conventional imaging. Most of the Gd contrast agents available have similar T1 and T2 relaxivities, and thus their contrast-enhancing capabilities are comparable. Exceptions are gadobenate-dimeglumine, Gd-EOB-DTPA, Gadobutrol and gadofosveset, which, owing to their transient-protein-binding capability, possess almost twice (and more) the T1 and T2 relaxivities as other agents at all magnetic field strengths. Numerous comparative studies have demonstrated the advantages of the increased relaxivity in terms of enhanced image contrast, image quality and diagnostic confidence. Here we summarise the benefits of higher relaxivity for the most common neuroimaging applications including MRI, perfusion-weighted imaging and MRA for evaluation of brain tumours, cerebrovascular disease and other CNS lesions. (orig.)

  17. Delayed gadolinium-enhanced MRI of cartilage (dGEMRIC) of cadaveric shoulders: comparison of contrast dynamics in hyaline and fibrous cartilage after intraarticular gadolinium injection.

    Science.gov (United States)

    Wiener, E; Hodler, J; Pfirrmann, C W A

    2009-01-01

    Delayed gadolinium-enhanced magnetic resonance imaging of cartilage (dGEMRIC) is a novel method to investigate cartilaginous and fibrocartilaginous structures. To investigate the contrast dynamics in hyaline and fibrous cartilage of the glenohumeral joint after intraarticular injection of gadopentetate dimeglumine. Transverse T(1) maps were acquired on a 1.5T scanner before and after intraarticular injection of 2.0 mmol/l gadopentetate dimeglumine in five cadaveric shoulders using a dual flip angle three-dimensional gradient echo (3D-GRE) sequence. The acquisition time for the T(1) maps was 5 min 5 s for the whole shoulder. Measurements were repeated every 15 min over 2.5 hours. Regions of interest (ROIs) covering the glenoid cartilage and the labrum were drawn to assess the temporal evolution of the relaxation parameters. T(1) of unenhanced hyaline cartilage of the glenoid was 568+/-34 ms. T(1) of unenhanced fibrous cartilage of the labrum was 552+/-38 ms. Significant differences (P=0.002 and 0.03) in the relaxation parameters were already measurable after 15 min. After 2 to 2.5 hours, hyaline and fibrous cartilage still demonstrated decreasing relaxation parameters, with a larger range of the T(1)(Gd) values in fibrous cartilage. T(1) and triangle Delta R(1) values of hyaline and fibrous cartilage after 2.5 hours were 351+/-16 ms and 1.1+/-0.09 s(-1), and 332+/-31 ms and 1.2+/-0.1 s(-1), respectively. A significant decrease in T(1)(Gd) was found 15 min after intraarticular contrast injection. Contrast accumulation was faster in hyaline than in fibrous cartilage. After 2.5 hours, contrast accumulation showed a higher rate of decrease in hyaline cartilage, but neither hyaline nor fibrous cartilage had reached equilibrium.

  18. Delayed Gadolinium-Enhanced MRI of Cartilage (dGEMRIC) of Cadaveric Shoulders: Comparison of Contrast Dynamics in Hyaline and Fibrous Cartilage after Intraarticular Gadolinium Injection

    Energy Technology Data Exchange (ETDEWEB)

    Wiener, E. (Dept. of Radiology, Charite Universitaetsmedizin Berlin (Germany)); Hodler, J.; Pfirrmann, C.W.A. (Dept. of Radiology, Orthopedic Univ. Hospital Balgrist, Zuerich (Switzerland))

    2009-01-15

    Background: Delayed gadolinium-enhanced magnetic resonance imaging of cartilage (dGEMRIC) is a novel method to investigate cartilaginous and fibrocartilaginous structures. Purpose: To investigate the contrast dynamics in hyaline and fibrous cartilage of the glenohumeral joint after intraarticular injection of gadopentetate dimeglumine. Material and Methods: Transverse T1 maps were acquired on a 1.5T scanner before and after intraarticular injection of 2.0 mmol/l gadopentetate dimeglumine in five cadaveric shoulders using a dual flip angle three-dimensional gradient echo (3D-GRE) sequence. The acquisition time for the T1 maps was 5 min 5 s for the whole shoulder. Measurements were repeated every 15 min over 2.5 hours. Regions of interest (ROIs) covering the glenoid cartilage and the labrum were drawn to assess the temporal evolution of the relaxation parameters. Results: T1 of unenhanced hyaline cartilage of the glenoid was 568+-34 ms. T1 of unenhanced fibrous cartilage of the labrum was 552+-38 ms. Significant differences (P=0.002 and 0.03) in the relaxation parameters were already measurable after 15 min. After 2 to 2.5 hours, hyaline and fibrous cartilage still demonstrated decreasing relaxation parameters, with a larger range of the T1(Gd) values in fibrous cartilage. T1 and ?R1 values of hyaline and fibrous cartilage after 2.5 hours were 351+-16 ms and 1.1+-0.09/s, and 332+-31 ms and 1.2+-0.1/s, respectively. Conclusion: A significant decrease in T1(Gd) was found 15 min after intraarticular contrast injection. Contrast accumulation was faster in hyaline than in fibrous cartilage. After 2.5 hours, contrast accumulation showed a higher rate of decrease in hyaline cartilage, but neither hyaline nor fibrous cartilage had reached equilibrium

  19. The Evaluation of Liver Function Using Liver-Specific MR Contrast Agents%MR特异性对比剂肝功能评价研究

    Institute of Scientific and Technical Information of China (English)

    冯汝静; 黄仲奎

    2013-01-01

    Objective To evaluate the application value of liver-specific contrast agents in evaluating liver function. Methods Thirty six patients with liver dysfunction underwent MRI enhanced examination using liver specific contrast a-gent,including Gd BOPTA in 28 cases and Gd EOB DTPA in 12 cases, as well as MR conventional raulti phase enhanced scan. The liver function were evaluated with the biliary display in the hepatobiliary excretion phase. Results According to the visibility score of biliary in the hepatobiliary excretion phase images, 33 patients' liver function can be classified as grade A (grade > 16 points) in 17 cases,grade B (6 to 15 points) in 10 cases,grade C (6 to 15 points)in 6 cases. The consistency of image grading and clinical Child-pugh grading for liver function were good in the 33 patients (K = 0. 570, P = 0. 000). Especially, excellent consistency was presented in 10 cases using Gd EOB DTPA agent (K = 0. 804, P = 0.000). Conclusion The liver function could be evaluated by the liver-specific contrast agent enhanced MR images.%目的 探讨MRI特异性对比剂对肝功能评价的应用价值.方法 选择2011年至2012年行肝脏MRI检查的33例肝功能障碍患者资料.行肝脏常规MRI平扫、肝脏MRI特异性对比剂[钆贝葡胺(Gd-BOPTA)26例,钆塞酸二钠(Gd-EOB-DTPA) 10例]增强,对肝胆排泄期的各级胆管显示情况进行5级评分,再根据各级胆管显示总评分进行肝功能MRI分级.结果 33例患者的肝功能MR分级与临床Child-Pugh分级一致性良好(K=0.570,P=o.ooo),其中10例Gd-EOB-DTPA增强肝功能MR分级与临床Child-Pugh分级吻合程度极佳(K=0.804,P=0.000).结论 观察肝脏MRI特异性对比剂增强肝胆排泄期的胆管显示情况,可以评价整个肝脏肝功能情况.

  20. Contrast-Enhanced Magnetic Resonance Cholangiography: Practical Tips and Clinical Indications for Biliary Disease Management.

    Science.gov (United States)

    Palmucci, Stefano; Roccasalva, Federica; Piccoli, Marina; Fuccio Sanzà, Giovanni; Foti, Pietro Valerio; Ragozzino, Alfonso; Milone, Pietro; Ettorre, Giovanni Carlo

    2017-01-01

    Since its introduction, MRCP has been improved over the years due to the introduction of several technical advances and innovations. It consists of a noninvasive method for biliary tree representation, based on heavily T2-weighted images. Conventionally, its protocol includes two-dimensional single-shot fast spin-echo images, acquired with thin sections or with multiple thick slabs. In recent years, three-dimensional T2-weighted fast-recovery fast spin-echo images have been added to the conventional protocol, increasing the possibility of biliary anatomy demonstration and leading to a significant benefit over conventional 2D imaging. A significant innovation has been reached with the introduction of hepatobiliary contrasts, represented by gadoxetic acid and gadobenate dimeglumine: they are excreted into the bile canaliculi, allowing the opacification of the biliary tree. Recently, 3D interpolated T1-weighted spoiled gradient echo images have been proposed for the evaluation of the biliary tree, obtaining images after hepatobiliary contrast agent administration. Thus, the acquisition of these excretory phases improves the diagnostic capability of conventional MRCP-based on T2 acquisitions. In this paper, technical features of contrast-enhanced magnetic resonance cholangiography are briefly discussed; main diagnostic tips of hepatobiliary phase are showed, emphasizing the benefit of enhanced cholangiography in comparison with conventional MRCP.

  1. Dynamic Contrast-Enhanced MRI of Cervical Cancers: Temporal Percentile Screening of Contrast Enhancement Identifies Parameters for Prediction of Chemoradioresistance

    Energy Technology Data Exchange (ETDEWEB)

    Andersen, Erlend K.F. [Department of Medical Physics, Oslo University Hospital, Oslo (Norway); Hole, Knut Hakon; Lund, Kjersti V. [Department of Radiology, Oslo University Hospital, Oslo (Norway); Sundfor, Kolbein [Department of Gynaecological Oncology, Oslo University Hospital, Oslo (Norway); Kristensen, Gunnar B. [Department of Gynaecological Oncology, Oslo University Hospital, Oslo (Norway); Institute for Medical Informatics, Oslo University Hospital, Oslo (Norway); Lyng, Heidi [Department of Radiation Biology, Oslo University Hospital, Oslo (Norway); Malinen, Eirik, E-mail: eirik.malinen@fys.uio.no [Department of Medical Physics, Oslo University Hospital, Oslo (Norway); Department of Physics, University of Oslo, Oslo (Norway)

    2012-03-01

    Purpose: To systematically screen the tumor contrast enhancement of locally advanced cervical cancers to assess the prognostic value of two descriptive parameters derived from dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI). Methods and Materials: This study included a prospectively collected cohort of 81 patients who underwent DCE-MRI with gadopentetate dimeglumine before chemoradiotherapy. The following descriptive DCE-MRI parameters were extracted voxel by voxel and presented as histograms for each time point in the dynamic series: normalized relative signal increase (nRSI) and normalized area under the curve (nAUC). The first to 100th percentiles of the histograms were included in a log-rank survival test, resulting in p value and relative risk maps of all percentile-time intervals for each DCE-MRI parameter. The maps were used to evaluate the robustness of the individual percentile-time pairs and to construct prognostic parameters. Clinical endpoints were locoregional control and progression-free survival. The study was approved by the institutional ethics committee. Results: The p value maps of nRSI and nAUC showed a large continuous region of percentile-time pairs that were significantly associated with locoregional control (p < 0.05). These parameters had prognostic impact independent of tumor stage, volume, and lymph node status on multivariate analysis. Only a small percentile-time interval of nRSI was associated with progression-free survival. Conclusions: The percentile-time screening identified DCE-MRI parameters that predict long-term locoregional control after chemoradiotherapy of cervical cancer.

  2. Can cerebrovascular reactivity be assessed by dynamic susceptibility contrast-enhanced MRI?

    Energy Technology Data Exchange (ETDEWEB)

    Berthezene, Y.; Meyer, R.; Froment, J.C. [Department of Radiology, Creatis UMR CNRS 5515, Neurological Hospital, Lyon (France); Nighoghossian, N.; Trouillas, P. [Neurology, Cerebrovascular Disease and Ataxia Research Center, Neurological Hospital, Lyon (France); Damien, J.; Cinotti, L. [Department of Nuclear Medicine, Neurological Hospital, Lyon (France); Adeleine, P. [Medical Informatics Laboratory, UFR Alexis Carrel, Lyon (France)

    1998-01-01

    s The acetazolamide (ACZ) test is performed to evaluate the decrease in cerebral perfusion pressure (CPP) by investigation of vasomotor reactivity (VMR). Our aim was to study cerebral blood flow and blood volume changes induced by the ACZ test in healthy control subjects using dynamic susceptibility contrast-enhanced gradient-echo MRI (DSC-MRI). A FLASH sequence was used to produce susceptibility-weighted images during an intravenous injection of 0.1 mmol/kg gadopentetate dimeglumine (Gd-DTPA). After the first dynamic study, 1 g acetazolamide was given intravenously and 10 min later a second bolus of Gd-DTPA was injected. Using the indicator-dilution theory, relative cerebral blood volume and relative cerebral blood flow were estimated. In healthy subjects the ACZ test induced a significant increase in relative blood volume (from 80.5 {+-} 10.7 to 113.4 {+-} 11.9) and relative blood flow (from 5.73 {+-} 0.96 to 7.5 {+-} 0.97), symmetrically in the cerebral hemispheres. This approach might be promising in the understanding of cerebral haemodynamics in patients with vascular disorders. (orig.) With 1 fig., 3 tabs., 24 refs.

  3. Magnetic resonance guided focused ultrasound surgery (MRgFUS) of bone metastases: From primary pain palliation to local tumor control

    Science.gov (United States)

    Napoli, A.; Leonardi, A.; Andrani, F.; Boni, F.; Anzidei, M.; Catalano, C.

    2017-03-01

    Purpose: To evaluate the clinical performance of MRgFUS in primary pain palliation of painful bone metastases and in local tumor control. Materials and Methods: We enrolled 26 consecutive patients (female/male 12/14; age: 64.7±7.5yrs) with painful bone metastases. Before and 3 months after MRgFUS treatment pain severity and pain interference scores were assessed according to Brief Pain Inventory-Quality of Life (BPI-QoL) criteria and patients underwent both CT and MRI. Local tumor control was evaluated according to lesion size, density and perfusion at CT, dynamic contrast enhancement at MRI (Discovery 750HD, GE; Gd-Bopta, Bracco) and metabolic activity at PET or scintigraphy. Patients were classified as responders or non-responders. Results: No treatment-related adverse events were recorded during the study. As statistically significant difference between baseline and follow-up values for both pain severity and pain interference scores was observed (pbreast primary cancer) there was nearly absence of metabolic activity after treatment (mean SUV=1.2). Conclusion: MRgFUS can be safely and effectively used as the primary treatment for pain palliation in patients with painful bone metastases; moreover our experience demonstrated also a potential role for the MRgFUS in local tumor control.

  4. Gadofluorine M-enhanced MRI shows involvement of circumventricular organs in neuroinflammation

    Directory of Open Access Journals (Sweden)

    Glumm Robert

    2010-10-01

    Full Text Available Abstract Background Circumventricular organs (CVO are cerebral areas with incomplete endothelial blood-brain barrier (BBB and therefore regarded as "gates to the brain". During inflammation, they may exert an active role in determining immune cell recruitment into the brain. Methods In a longitudinal study we investigated in vivo alterations of CVO during neuroinflammation, applying Gadofluorine M- (Gf enhanced magnetic resonance imaging (MRI in experimental autoimmune encephalomyelitis, an animal model of multiple sclerosis. SJL/J mice were monitored by Gadopentate dimeglumine- (Gd-DTPA and Gf-enhanced MRI after adoptive transfer of proteolipid-protein-specific T cells. Mean Gf intensity ratios were calculated individually for different CVO and correlated to the clinical disease course. Subsequently, the tissue distribution of fluorescence-labeled Gf as well as the extent of cellular inflammation was assessed in corresponding histological slices. Results We could show that the Gf signal intensity of the choroid plexus, the subfornicular organ and the area postrema increased significantly during experimental autoimmune encephalomyelitis, correlating with (1 disease severity and (2 the delay of disease onset after immunization. For the choroid plexus, the extent of Gf enhancement served as a diagnostic criterion to distinguish between diseased and healthy control mice with a sensitivity of 89% and a specificity of 80%. Furthermore, Gf improved the detection of lesions, being particularly sensitive to optic neuritis. In correlated histological slices, Gf initially accumulated in the extracellular matrix surrounding inflammatory foci and was subsequently incorporated by macrophages/microglia. Conclusion Gf-enhanced MRI provides a novel highly sensitive technique to study cerebral BBB alterations. We demonstrate for the first time in vivo the involvement of CVO during the development of neuroinflammation.

  5. Radiation-Induced Liver Damage: Correlation of Histopathology with Hepatobiliary Magnetic Resonance Imaging, a Feasibility Study

    Energy Technology Data Exchange (ETDEWEB)

    Seidensticker, Max, E-mail: max.seidensticker@med.ovgu.de [Universitätsklinik Magdeburg, Klinik für Radiologie und Nuklearmedizin (Germany); Burak, Miroslaw [Pomeranian Medical University, Department of Diagnostic Imaging and Interventional Radiology (Poland); Kalinski, Thomas [Universitätsklinik Magdeburg, Institut für Pathologie (Germany); Garlipp, Benjamin [Universitätsklinik Magdeburg, Klinik für Allgemein-, Viszeral- und Gefäßchirurgie (Germany); Koelble, Konrad [Philipps Universität Marburg, Fachbereich Medizin der, Abteilung für Neuropathologie (Germany); Wust, Peter [Charité Universitätsmedizin Berlin, Klinik für Radioonkologie und Strahlentherapie (Germany); Antweiler, Kai [Universitätsklinik Magdeburg, Institut für Biometrie und Medizinische Informatik (Germany); Seidensticker, Ricarda; Mohnike, Konrad; Pech, Maciej; Ricke, Jens [Universitätsklinik Magdeburg, Klinik für Radiologie und Nuklearmedizin (Germany)

    2015-02-15

    PurposeRadiotherapy of liver malignancies shows promising results (radioembolization, stereotactic irradiation, interstitial brachytherapy). Regardless of the route of application, a certain amount of nontumorous liver parenchyma will be collaterally damaged by radiation. The functional reserve may be significantly reduced with an impact on further treatment planning. Monitoring of radiation-induced liver damage by imaging is neither established nor validated. We performed an analysis to correlate the histopathological presence of radiation-induced liver damage with functional magnetic resonance imaging (MRI) utilizing hepatobiliary contrast media (Gd-BOPTA).MethodsPatients undergoing local high-dose-rate brachytherapy for whom a follow-up hepatobiliary MRI within 120 days after radiotherapy as well as an evaluable liver biopsy from radiation-exposed liver tissue within 7 days before MRI were retrospectively identified. Planning computed tomography (CT)/dosimetry was merged to the CT-documentation of the liver biopsy and to the MRI. Presence/absence of radiation-induced liver damage (histopathology) and Gd-BOPTA uptake (MRI) as well as the dose applied during brachytherapy at the site of tissue sampling was determined.ResultsFourteen biopsies from eight patients were evaluated. In all cases with histopathological evidence of radiation-induced liver damage (n = 11), no uptake of Gd-BOPTA was seen. In the remaining three, cases no radiation-induced liver damage but Gd-BOPTA uptake was seen. Presence of radiation-induced liver damage and absence of Gd-BOPTA uptake was correlated with a former high-dose exposition.ConclusionsAbsence of hepatobiliary MRI contrast media uptake in radiation-exposed liver parenchyma may indicate radiation-induced liver damage. Confirmatory studies are warranted.

  6. Transient Severe Motion Artifact Related to Gadoxetate Disodium-Enhanced Liver MRI: Frequency and Risk Evaluation at a German Institution.

    Science.gov (United States)

    Well, Lennart; Rausch, Vanessa Hanna; Adam, Gerhard; Henes, Frank Oliver; Bannas, Peter

    2017-07-01

    Purpose Varying frequencies (5 - 18 %) of contrast-related transient severe motion (TSM) imaging artifacts during gadoxetate disodium-enhanced arterial phase liver MRI have been reported. Since previous reports originated from the United States and Japan, we aimed to determine the frequency of TSM at a German institution and to correlate it with potential risk factors and previously published results. Materials and Methods Two age- and sex-matched groups were retrospectively selected (gadoxetate disodium n = 89; gadobenate dimeglumine n = 89) from dynamic contrast-enhanced MRI examinations in a single center. Respiratory motion-related artifacts in non-enhanced and dynamic phases were assessed independently by two readers blinded to contrast agents on a 4-point scale. Scores of ≥ 3 were considered as severe motion artifacts. Severe motion artifacts in arterial phases were considered as TSM if scores in all other phases were  0.05). Conclusion We revealed a high frequency of TSM after injection of gadoxetate disodium at a German institution, substantiating the importance of a diagnosis-limiting phenomenon that so far has only been reported from the United States and Japan. In accordance with previous studies, we did not identify associated risk factors for TSM. Key Points:  · Gadoxetate disodium causes TSM in a relevant number of patients.. · The frequency of TSM is similar between the USA, Japan and Germany.. · To date, no validated risk factors for TSM could be identified.. Citation Format · Well L, Rausch VH, Adam G et al. Transient Severe Motion Artifact Related to Gadoxetate Disodium-Enhanced Liver MRI: Frequency and Risk Evaluation at a German Institution. Fortschr Röntgenstr 2017; 189: 651 - 660. © Georg Thieme Verlag KG Stuttgart · New York.

  7. Myocardial delayed contrast enhancement in patients with arterial hypertension: Initial results of cardiac MRI

    Energy Technology Data Exchange (ETDEWEB)

    Andersen, Kjel [Institute of Diagnostic Radiology, University Hospital Duesseldorf, Moorenstr. 5, 40225 Duesseldorf (Germany)], E-mail: kjel_andersen@web.de; Hennersdorf, Marcus [Department of Cardiology, University Hospital Duesseldorf, Moorenstr. 5, 40225 Duesseldorf (Germany)], E-mail: hennersdorf@med.uni-duesseldorf.de; Cohnen, Mathias [Institute of Diagnostic Radiology, University Hospital Duesseldorf, Moorenstr. 5, 40225 Duesseldorf (Germany)], E-mail: cohnen@med.uni-duesseldorf.de; Blondin, Dirk [Institute of Diagnostic Radiology, University Hospital Duesseldorf, Moorenstr. 5, 40225 Duesseldorf (Germany)], E-mail: blondin@med.uni-duesseldorf.de; Moedder, Ulrich [Institute of Diagnostic Radiology, University Hospital Duesseldorf, Moorenstr. 5, 40225 Duesseldorf (Germany)], E-mail: moedder@uni-duesseldorf.de; Poll, Ludger W. [Institute of Diagnostic Radiology, University Hospital Duesseldorf, Moorenstr. 5, 40225 Duesseldorf (Germany)], E-mail: poll@gmx.de

    2009-07-15

    Purpose: In arterial hypertension left ventricular hypertrophy comprises myocyte hypertrophy, interstitial fibrosis and structural alterations of the coronary microcirculation. MRI enables the detection of myocardial fibrosis, infarction and scar tissue by delayed enhancement (DE) after contrast media application. Aim of this study was to investigate patients with arterial hypertension but without known coronary disease or previous myocardial infarction to detect areas of DE. Methods and material: Twenty patients with arterial hypertension with clinical symptoms of myocardial ischemia, but without history of myocardial infarction and normal coronary arteries during coronary angiography were investigated on a 1.0 T superconducting magnet (Gyroscan T10-NT, Intera Release 8.0, Philips). Fast gradient-echo cine sequences and T2-weighted STIR-sequences were acquired. Fifteen minutes after injection of Gadobenate dimeglumine inversion recovery gradient-echo sequences were performed for detection of myocardial DE. Presence or absence of DE on MRI was correlated with clinical data and the results of echocardiography and electrocardiography, respectively. Results: Nine of 20 patients showed DE in the interventricular septum and the anteroseptal left ventricular wall. In 6 patients, DE was localized intramurally and in 3 patients subendocardially. There was a significant correlation between myocardial DE and ST-segment depressions during exercise and between DE and left-ventricular enddiastolic pressure. Patients with intermittent atrial fibrillation showed a myocardial DE more often than patients without atrial fibrillation. Conclusion: In our series, 45% of patients with arterial hypertension showed DE on cardiac MRI. In this clinical setting, delayed enhancement may be due to coronary microangiopathy. The more intramurally localization of DE, however, rather indicates myocardial interstitial fibrosis.

  8. Indirect MR arthrography of anterior shoulder instability in the ABER and the apprehension test positions: a prospective comparative study of two different shoulder positions during MRI using intravenous gadodiamide contrast for enhancement of the joint fluid

    Energy Technology Data Exchange (ETDEWEB)

    Wintzell, G.; Larsson, S. [Uppsala University Hospital (Sweden). Dept. of Orthopaedics; Larsson, H. [Nacka-Soeder Hospital, Stockholm (Sweden). Dept. of Radiology

    1998-09-01

    The value of MRI for the evaluation of anterior shoulder instability can be enhanced by shoulder positions that stress the stabilising structures. The ABER position is one that has been described in combination with intra-articular gadopentetate dimeglumine arthrography. We believe that MRI in the Apprehension test position with 90 abduction and maximal tolerable external rotation provides maximum tension on the anterior stabilising structures and with this technique it is sufficient to use indirect gadodiamide arthrography following intravenous injection of the contrast medium. The purpose of this study was to make a prospective comparative evaluation of the ABER and Apprehension test positions when using indirect arthrography with intravenous gadodiamide administration in shoulders with anterior instability. Results. Both the ABER and the Apprehension test position were useful techniques in detecting capsulolabral pathology and Hill-Sachs lesions. The Apprehension test position produced significantly better gadodiamide-enhanced joint fluid in the region of pathology in both the capsulolabral lesion and the Hill-Sachs lesion. It also visualised the size of the Hill-Sachs lesion significantly better than did the ABER position. (orig.)

  9. Application of Benchtop-magnetic resonance imaging in a nude mouse tumor model

    Directory of Open Access Journals (Sweden)

    Mäder Karsten

    2011-07-01

    Full Text Available Abstract Background MRI plays a key role in the preclinical development of new drugs, diagnostics and their delivery systems. However, very high installation and running costs of existing superconducting MRI machines limit the spread of MRI. The new method of Benchtop-MRI (BT-MRI has the potential to overcome this limitation due to much lower installation and almost no running costs. However, due to the low field strength and decreased magnet homogeneity it is questionable, whether BT-MRI can achieve sufficient image quality to provide useful information for preclinical in vivo studies. It was the aim of the current study to explore the potential of BT-MRI on tumor models in mice. Methods We used a prototype of an in vivo BT-MRI apparatus to visualise organs and tumors and to analyse tumor progression in nude mouse xenograft models of human testicular germ cell tumor and colon carcinoma. Results Subcutaneous xenografts were easily identified as relative hypointense areas in transaxial slices of NMR images. Monitoring of tumor progression evaluated by pixel extension analyses based on NMR images correlated with increasing tumor volume calculated by calliper measurement. Gd-BOPTA contrast agent injection resulted in a better differentiation between parts of the urinary tissues and organs due to fast elimination of the agent via kidneys. In addition, interior structuring of tumors could be observed. A strong contrast enhancement within a tumor was associated with a central necrotic/fibrotic area. Conclusions BT-MRI provides satisfactory image quality to visualize organs and tumors and to monitor tumor progression and structure in mouse models.

  10. Low-dose contrast-enhanced time-resolved MR angiography at 3T: diagnostic accuracy for treatment planning and follow-up of vascular malformations.

    Science.gov (United States)

    Anzidei, M; Cavallo Marincola, B; Napoli, A; Saba, L; Zaccagna, F; Lucatelli, P; Fanelli, F; Bassetti, E; Salvatori, F M; Catalano, C; Passariello, R

    2011-12-01

    To assess the accuracy of low-dose contrast-enhanced time-resolved 3T magnetic resonance angiography (MRA) for the morphological and functional assessment of vascular malformations (VM), and to evaluate its diagnostic potential for the depiction of treatment-induced changes. Twenty-five patients with known VM underwent MRA to evaluate the location and extent of lesions and their haemodynamic characteristics. Three-dimensional (3D) T1-weighted time-resolved sequences were acquired following the administration of 0.05mmol/kg of gadobenate dimeglumine. VM were classified according to their morphology and haemodynamic characteristics. All patients thereafter underwent conventional angiography to confirm the diagnosis and to treat the lesions (embolization or sclerotherapy). Follow-up MRA was performed 30 days after treatment to assess morphological and functional changes. A visual analogue scale (VAS) was used to clinically assess the severity of symptoms before and after therapy. Based on haemodynamic characteristics, VM were classified as predominantly arterial [4 (16%)], artero-venous [19 (76%)] or venous [2 (8%)]. Twenty-three (92%) lesions were classified as high-flow VM and two (8%) as low-flow VM. Intralesional thrombosis was present in 17 (68%) lesions before therapy and in 10 lesions (40%) after therapy. The median VAS scores were 5±1 before treatment and 4±2 after treatment. Very good correlation (Spearman's correlation coefficient: rho=0.87; p=0.000) was noted between the reduction of lesion size on follow-up MRA and pain relief as assessed by VAS. Low-dose contrast-enhanced time-resolved 3T MRA can be used to define morphological and functional aspects of VM accurately during treatment planning and follow-up, and can identify post-therapy changes that positively correlate with treatment outcome. 2011 The Royal College of Radiologists. Published by Elsevier Ltd. All rights reserved.

  11. Low-dose contrast-enhanced time-resolved MR angiography at 3 T: Diagnostic accuracy for treatment planning and follow-up of vascular malformations

    Energy Technology Data Exchange (ETDEWEB)

    Anzidei, M., E-mail: michele.anzidei@gmail.com [Department of Radiological Sciences, University of Rome ' La Sapienza' , Rome (Italy); Cavallo Marincola, B.; Napoli, A. [Department of Radiological Sciences, University of Rome ' La Sapienza' , Rome (Italy); Saba, L. [University of Cagliari, Polo Ospedaliero Monserrato (Italy); Zaccagna, F.; Lucatelli, P.; Fanelli, F.; Bassetti, E.; Salvatori, F.M.; Catalano, C.; Passariello, R. [Department of Radiological Sciences, University of Rome ' La Sapienza' , Rome (Italy)

    2011-12-15

    Aim: To assess the accuracy of low-dose contrast-enhanced time-resolved 3 T magnetic resonance angiography (MRA) for the morphological and functional assessment of vascular malformations (VM), and to evaluate its diagnostic potential for the depiction of treatment-induced changes. Materials and methods: Twenty-five patients with known VM underwent MRA to evaluate the location and extent of lesions and their haemodynamic characteristics. Three-dimensional (3D) T1-weighted time-resolved sequences were acquired following the administration of 0.05 mmol/kg of gadobenate dimeglumine. VM were classified according to their morphology and haemodynamic characteristics. All patients thereafter underwent conventional angiography to confirm the diagnosis and to treat the lesions (embolization or sclerotherapy). Follow-up MRA was performed 30 days after treatment to assess morphological and functional changes. A visual analogue scale (VAS) was used to clinically assess the severity of symptoms before and after therapy. Results: Based on haemodynamic characteristics, VM were classified as predominantly arterial [4 (16%)], artero-venous [19 (76%)] or venous [2 (8%)]. Twenty-three (92%) lesions were classified as high-flow VM and two (8%) as low-flow VM. Intralesional thrombosis was present in 17 (68%) lesions before therapy and in 10 lesions (40%) after therapy. The median VAS scores were 5 {+-} 1 before treatment and 4 {+-} 2 after treatment. Very good correlation (Spearman's correlation coefficient: rho = 0.87; p = 0.000) was noted between the reduction of lesion size on follow-up MRA and pain relief as assessed by VAS. Conclusion: Low-dose contrast-enhanced time-resolved 3 T MRA can be used to define morphological and functional aspects of VM accurately during treatment planning and follow-up, and can identify post-therapy changes that positively correlate with treatment outcome.

  12. Gadobutrol Versus Gadopentetate Dimeglumine or Gadobenate Dimeglumine Before DCE-MRI in Diagnosing Patients With Multiple Sclerosis, Grade II-IV Glioma, or Brain Metastases

    Science.gov (United States)

    2016-11-15

    Adult Anaplastic (Malignant) Meningioma; Adult Anaplastic Astrocytoma; Adult Anaplastic Ependymoma; Adult Anaplastic Oligodendroglioma; Adult Brain Stem Glioma; Adult Choroid Plexus Neoplasm; Adult Diffuse Astrocytoma; Adult Ependymoblastoma; Adult Ependymoma; Adult Giant Cell Glioblastoma; Adult Glioblastoma; Adult Gliosarcoma; Adult Grade II Meningioma; Adult Medulloblastoma; Adult Mixed Glioma; Adult Oligodendroglioma; Adult Papillary Meningioma; Adult Pineal Gland Astrocytoma; Adult Pineoblastoma; Adult Primary Melanocytic Lesion of Meninges; Adult Supratentorial Primitive Neuroectodermal Tumor; Malignant Adult Intracranial Hemangiopericytoma; Metastatic Malignant Neoplasm in the Brain; Multiple Sclerosis; Recurrent Adult Brain Neoplasm

  13. Contrast enhanced IR-SSFP examination compared with T1-weighted turbo spin-echo imaging of cardiac tumors and tumorlike lesions

    Energy Technology Data Exchange (ETDEWEB)

    Bauner, K.U., E-mail: Kerstin.Bauner@med.uni-muenchen.de [Department of Clinical Radiology, University Hospitals - Campus Grosshadern, Ludwig-Maximilian University, Marchioninistr. 15, 81377 Munich (Germany); Sandner, T.; Notohamiprodjo, M. [Department of Clinical Radiology, University Hospitals - Campus Grosshadern, Ludwig-Maximilian University, Marchioninistr. 15, 81377 Munich (Germany); Schmoeckel, M. [Department of Cardiac Surgery, University Hospitals - Campus Grosshadern, Ludwig-Maximilian University, Marchioninistr. 15, 81377 Munich (Germany); Reiser, M.F.; Huber, A.M. [Department of Clinical Radiology, University Hospitals - Campus Grosshadern, Ludwig-Maximilian University, Marchioninistr. 15, 81377 Munich (Germany)

    2011-04-15

    Purpose: To show that the use of an early and delayed contrast enhanced multislice inversion recovery steady state free precession (SS-IR-SSFP) is a valuable substitute for conventional post-contrast fat saturated turbo spin-echo (TSE) T1-weighted images in the assessment of cardiac tumors. Materials and methods: 34 consecutive patients referred for MRI in order to assess cardiac tumors were examined. Shortly after administration of gadopenetate dimeglumine (Gd-DTPA) images were obtained using a SS-IR-SSFP sequence. The inversion time (TI) was set at 350 ms to achieve a good demarcation of intracavitary tumor spread. Hereafter 9 slices of a T1w TSE sequence were obtained. Finally a SS-IR-SSFP sequence with an optimized TI to null normal myocardium was employed. Quantitative comparisons were performed by calculating contrast to noise ratios of tumor/myocardium (CNR{sub tumor/myo}) and CNR of tumor/left ventricular cavity (CNR{sub tumor/LVC}). Image quality was assessed regarding overall image quality, artifacts and tumor conspicuity. Results: Neither calculation of CNR{sub tumor/LVC} when comparing the early IR-SSFP and T1w TSE, nor calculation of CNR{sub tumor/myo} when comparing the late IR-SSFP and T1w TSE sequence resulted in statistically significant differences. However, qualitative assessments revealed significant superior results for the early and the late IR-SSFP images compared to the T1-weighted TSE images (p < 0.001). Conclusions: Image quality and tumor conspicuity were superior and image degradation by artifacts was less on IR-SSFP images compared to TSE images without loss of CNR. Thus the use of IR-SSFP sequences is an attractive alternative imaging method compared to post-contrast T1w TSE imaging in the assessment of cardiac tumors.

  14. Complications after liver transplantation: evaluation with magnetic resonance imaging, magnetic resonance cholangiography, and 3-dimensional contrast-enhanced magnetic resonance angiography in a single session

    Energy Technology Data Exchange (ETDEWEB)

    Boraschi, P.; Donati, F.; Gigoni, R. [Pisa Univ. Hospital, Second Dept. of Radiology, Pisa (Italy)], E-mail: p.boraschi@do.med.unipi.it; Salemi, S. [Univ. of Pisa, Diagnostic and Interventional Radiology, Pisa (Italy); Urbani, L.; Filipponi, F. [Univ. of Pisa, Liver Transplant Unit of the Dept. of Oncology, Transplants and Advanced Technologies in Medicine, Pisa (Italy); Falaschi, F. [Pisa Univ. Hospital, Second Dept. of Radiology, Pisa (Italy); Bartolozzi, C. [Univ. of Pisa, Diagnostic and Interventional Radiology, Pisa (Italy)

    2008-12-15

    To evaluate a comprehensive magnetic resonance imaging (MRI) protocol as noninvasive diagnostic modality for simultaneous detection of parenchymal, biliary, and vascular complications after liver transplantation. Fifty-two liver transplant recipients suspected to have parenchymal, biliary, and (or) vascular complications underwent our MRI protocol at 1.5T unit using a phased array coil. After preliminary acquisition of axial T{sub 1}w and T{sub 2}w sequences, magnetic resonance cholangiography (MRC) was performed through a breath-hold, thin- and thick-slab, single-shot T{sub 2}w sequence in the coronal plane. Contrast-enhanced magnetic resonance angiography (CEMRA) was obtained using a 3-dimensional coronal spoiled gradient-echo sequence, which enabled acquisition of 32 partitions 2.0 mm thick. A fixed dose of 20 ml gadobenate dimeglumine was administered at 2 mL/s. A post-contrast T{sub 1}w sequence was also performed. Two observers in conference reviewed source images and 3-dimensional reconstructions to determine the presence of parenchymal, biliary, and vascular complications. MRI findings were correlated with surgery, endoscopic retrograde cholangiography (ERC), biopsy, digital subtraction angiography (DSA), and imaging follow-up. MRI revealed abnormal findings in 32 out of 52 patients (61%), including biliary complications (anastomotic and nonanastomotic strictures, and lithiasis) in 31, vascular disease (hepatic artery stenosis and thrombosis) in 9, and evidence of hepatic abscess and hematoma in 2. ERC confirmed findings of MRC in 30 cases, but suggested disease underestimation in 2. DSA confirmed 7 magnetic resonance angiogram (MRA) findings, but suggested disease overestimation in 2. MRI combined with MRC and CEMRA can provide a comprehensive assessment of parenchymal, biliary, and vascular complications in most recipients of liver transplantation. (author)

  15. Accuracy and feasibility of dynamic contrast-enhanced 3D MR imaging in the assessment of lung perfusion: comparison with Tc-99 MAA perfusion scintigraphy.

    Science.gov (United States)

    Yilmaz, E; Akkoclu, A; Degirmenci, B; Cooper, R A; Sengun, B; Gulcu, A; Osma, E; Ucan, E S

    2005-08-01

    The aim of this study was to correlate findings of perfusion magnetic resonance imaging (MRI) and perfusion scintigraphy in cases where there was a suspicion of abnormal pulmonary vasculature, and to evaluate the usefulness of MRI in the detection of perfusion deficits of the lung. In all, 17 patients with suspected abnormality of the pulmonary vasculature underwent dynamic contrast-enhanced MRI. T1-weighted 3D fast-field echo pulse sequences were obtained (TR/TE 3.3/1.58 ms; flip angle 30 degrees; slice thickness 12 to 15 mm). The dynamic study was acquired in the coronal plane following administration of 0.1 mmol/kg gadopentetate dimeglumine. A total of 8 to 10 sections repeated 20 to 25 times at intervals of 1s were performed. Perfusion lung scintigraphy was carried out a maximum of 48 h before the MR examination in all cases. Two radiologists, who were blinded to the clinical data and results of other imaging methods, reviewed all coronal sections. MR perfusion images were independently assessed in terms of segmental or lobar perfusion defects in the 85 lobes of the 17 individuals, and the findings were compared with the results of scintigraphy. Of the 17 patients, 8 were found to have pulmonary emboli, 2 chronic obstructive pulmonary disease with emphysema, 2 bullous emphysema, 2 Takayasu arteritis and 1 had a hypoplastic pulmonary artery. Pulmonary perfusion was completely normal in 2 cases. In 35 lobes, perfusion defects were detected using both methods, in 4 with MR alone and in 9 only with scintigraphy. There was good agreement between MRI and scintigraphy findings (kappa=0.695). Pulmonary perfusion MRI is a new alternative to scintigraphy in the evaluation of pulmonary perfusion for various lung disorders. In addition, this technique allows measurement and quantification of pulmonary perfusion abnormalities.

  16. Segmental Difference of the Hepatic Fibrosis from Chronic Viral Hepatitis due to Hepatitis B versus C Virus Infection: Comparison Using Dual Contrast Material-Enhanced MRI

    Energy Technology Data Exchange (ETDEWEB)

    Shin, Jae Ho; Yu, Jeong Sik; Chung, Jae Joon; Kim, Joo Hee; Kim, Ki Whang [Gangnam Severance Hospital, Yensei University College of Medicine, Seoul (Korea, Republic of)

    2011-08-15

    We wanted to identify the geographic differences in hepatic fibrosis and their associations with the atrophy-hypertrophy complex in patients with chronic viral hepatitis using the dual-contrast material-enhanced MRI (DC-MRI) with gadopentetate dimeglumine and ferucarbotran. Patients with chronic C (n = 22) and B-viral hepatitis (n = 35) were enrolled for determining the subjective grade of fibrosis (the extent and thickness of fibrotic reticulations) in the right lobe (RL), the caudate lobe (CL), the medial segment (MS) and the lateral segment (LS) of the liver, with using a 5-grade scale, on the gradient echo T2-weighted images of DC-MRI. The fibrosis grades of different segments were compared using the Kruskal-Wallis test followed by post-hoc analysis to establish the segment-by-segment differences. The incidences of two pre-established morphologic signs of cirrhosis were also compared with each other between the two groups of patients. There were significant intersegmental differences in fibrosis grades of the C-viral group (p = 0.005), and the CL showed lower fibrosis grades as compared with the grades of the RL and MS, whereas all lobes were similarly affected in the B-viral group (p = 0.221). The presence of a right posterior hepatic notch was significantly higher in the patients with intersegmental differences of fibrosis between the RL and the CL (19 out of 25, 76%) than those without such differences (6 out of 32, 19%) (p < 0.001). An expanded gallbladder fossa showed no significant relationship (p = 0.327) with the segmental difference of the fibrosis grades between the LS and the MS. The relative lack of fibrosis in the CL with more advanced fibrosis in the RL can be a distinguishing feature to differentiate chronic C-viral hepatitis from chronic B-viral hepatitis and this is closely related to the presence of a right posterior hepatic notch.

  17. Immediate Adverse Reactions to Gadolinium-Based MR Contrast Media: A Retrospective Analysis on 10,608 Examinations

    Science.gov (United States)

    Fusco, Roberta; dell'Aprovitola, Nicoletta; Catalano, Orlando; Filice, Salvatore; Schiavone, Vincenzo; Izzo, Francesco; Cuomo, Arturo

    2016-01-01

    Background and Purpose. Contrast media (CM) for magnetic resonance imaging (MRI) may determine the development of acute adverse reactions. Objective was to retrospectively assess the frequency and severity of adverse reactions associated with gadolinium-based contrast agents (GBCAs) injection in patients who underwent MRI. Material and Methods. At our center 10608 MRI examinations with CM were performed using five different GBCAs: Gd-BOPTA (MultiHance), Gd-DTPA (Magnevist), Gd-EOBDTPA (Primovist), Gd-DOTA (Dotarem), and Gd-BTDO3A (Gadovist). Results. 32 acute adverse reactions occurred, accounting for 0.3% of all administration. Twelve reactions were associated with Gd-DOTA injection (0.11%), 9 with Gd-BOPTA injection (0.08%), 6 with Gd-BTDO3A (0.056%), 3 with Gd-EOB-DTPA (0.028%), and 2 with Gd-DTPA (0.018%). Twenty-four reactions (75.0%) were mild, four (12.5%) moderate, and four (12.5%) severe. The most severe reactions were seen associated with use of Gd-BOPTA, with 3 severe reactions in 32 total reactions. Conclusion. Acute adverse reactions are generally rare with the overall adverse reaction rate of 0.3%. The most common adverse reactions were not severe, consisting in skin rash and hives. PMID:27652261

  18. Tip enhancement

    CERN Document Server

    Kawata, Satoshi

    2007-01-01

    This book discusses the recent advances in the area of near-field Raman scattering, mainly focusing on tip-enhanced and surface-enhanced Raman scattering. Some of the key features covered here are the optical structuring and manipulations, single molecule sensitivity, analysis of single-walled carbon nanotubes, and analytic applications in chemistry, biology and material sciences. This book also discusses the plasmonic materials for better enhancement, and optical antennas. Further, near-field microscopy based on second harmonic generation is also discussed. Chapters have been written by some of the leading scientists in this field, who present some of their recent work in this field.·Near-field Raman scattering·Tip-enhanced Raman spectroscopy·Surface-enhanced Raman spectroscopy·Nano-photonics·Nanoanalysis of Physical, chemical and biological materials beyond the diffraction limits·Single molecule detection

  19. Intraindividual comparison of T1 relaxation times after gadobutrol and Gd-DTPA administration for cardiac late enhancement imaging

    Energy Technology Data Exchange (ETDEWEB)

    Doeblin, Patrick, E-mail: Patrick.doeblin@charite.de [Department of Cardiology, Charité – Universitätsmedizin Berlin, Charité Campus Benjamin Franklin, Berlin (Germany); Schilling, Rene, E-mail: rene.schilling@charite.de [Department of Radiology, Charité – Universitätsmedizin Berlin, Charité Campus Mitte, Berlin (Germany); Wagner, Moritz, E-mail: moritz.wagner@charite.de [Department of Radiology, Charité – Universitätsmedizin Berlin, Charité Campus Mitte, Berlin (Germany); Luhur, Reny, E-mail: renyluhur@yahoo.com [Department of Radiology, Charité – Universitätsmedizin Berlin, Charité Campus Mitte, Berlin (Germany); Huppertz, Alexander, E-mail: alexander.huppertz@charite.de [Department of Radiology, Charité – Universitätsmedizin Berlin, Charité Campus Mitte, Berlin (Germany); Imaging Science Institute, Charité, Berlin (Germany); Hamm, Bernd, E-mail: bernd.hamm@charite.de [Department of Radiology, Charité – Universitätsmedizin Berlin, Charité Campus Mitte, Berlin (Germany); Taupitz, Matthias, E-mail: matthias.taupitz@harite.de [Department of Radiology, Charité – Universitätsmedizin Berlin, Charité Campus Mitte, Berlin (Germany); and others

    2014-04-15

    Purpose: To evaluate T1-relaxation times of chronic myocardial infarction (CMI) using gadobutrol and gadopentetate dimeglumine (Gd-DTPA) over time and to determine the optimal imaging window for late enhancement imaging with both contrast agents. Material and methods: Twelve patients with CMI were prospectively included and examined on a 1.5 T magnetic resonance (MR) system using relaxivity-adjusted doses of gadobutrol (0.15 mmol/kg) and Gd-DTPA (0.2 mmol/kg) in random order. T1-relaxation times of remote myocardium (RM), infarcted myocardium (IM), and left ventricular cavity (LVC) were assessed from short-axis TI scout imaging using the Look–Locker approach and compared intraindividually using a Wilcoxon paired signed-rank test (α < 0.05). Results: Within 3 min of contrast agent administration (CA), IM showed significantly lower T1-relaxation times than RM with both contrast agents, indicating beginning cardiac late enhancement. Differences between gadobutrol and Gd-DTPA in T1-relaxation times of IM and RM were statistically not significant through all time points. However, gadobutrol led to significantly higher T1-relaxation times of LVC than Gd-DTPA from 6 to 9 min (220 ± 15 ms vs. 195 ± 30 ms p < 0.01) onwards, resulting in a significantly greater ΔT1 of IM to LVC at 9–12 min (−20 ± 35 ms vs. 0 ± 35 ms, p < 0.05) and 12–15 min (−25 ± 45 ms vs. −10 ± 60 ms, p < 0.05). Using Gd-DTPA, comparable ΔT1 values were reached only after 25–35 min. Conclusion: This study indicates good delineation of IM to RM with both contrast agents as early as 3 min after administration. However, we found significant differences in T1 relaxation times with greater ΔT1 IM–LVC using 0.15 mmol/kg gadobutrol compared to 0.20 mmol/kg Gd-DTPA after 9–15 min post-CA suggesting earlier differentiability of IM and LVC using gadobutrol.

  20. Speech enhancement

    CERN Document Server

    Benesty, Jacob; Chen, Jingdong

    2006-01-01

    We live in a noisy world! In all applications (telecommunications, hands-free communications, recording, human-machine interfaces, etc.) that require at least one microphone, the signal of interest is usually contaminated by noise and reverberation. As a result, the microphone signal has to be ""cleaned"" with digital signal processing tools before it is played out, transmitted, or stored.This book is about speech enhancement. Different well-known and state-of-the-art methods for noise reduction, with one or multiple microphones, are discussed. By speech enhancement, we mean not only noise red

  1. A model of the dual effect of gadopentetate dimeglumine on dynamic brain MR images

    NARCIS (Netherlands)

    Barbier, EL; den Boer, JA; Rozeboom, AR; Sau, J; Bonmartin, A

    1999-01-01

    An optimized dynamic gradient echo sequence with two echoes is used to obtain data that can be analyzed with indicator dilution theory as well as with pharmacokinetic theory. Taking advantage of the simultaneity of T*(2) and T-1 information, both theories can be employed and merged to interpret cons

  2. Speech Enhancement

    DEFF Research Database (Denmark)

    Benesty, Jacob; Jensen, Jesper Rindom; Christensen, Mads Græsbøll;

    of methods and have been introduced in somewhat different contexts. Linear filtering methods originate in stochastic processes, while subspace methods have largely been based on developments in numerical linear algebra and matrix approximation theory. This book bridges the gap between these two classes......Speech enhancement is a classical problem in signal processing, yet still largely unsolved. Two of the conventional approaches for solving this problem are linear filtering, like the classical Wiener filter, and subspace methods. These approaches have traditionally been treated as different classes...... of methods by showing how the ideas behind subspace methods can be incorporated into traditional linear filtering. In the context of subspace methods, the enhancement problem can then be seen as a classical linear filter design problem. This means that various solutions can more easily be compared...

  3. EDITORIAL: Enhancing nanolithography Enhancing nanolithography

    Science.gov (United States)

    Demming, Anna

    2012-01-01

    Lithography was invented in late 18th century Bavaria by an ambitious young playwright named Alois Senefelder. Senefelder experimented with stone, wax, water and ink in the hope of finding a way of reproducing text so that he might financially gain from a wider distribution of his already successful scripts. His discovery not only facilitated the profitability of his plays, but also provided the world with an affordable printing press that would ultimately democratize the dissemination of art, knowledge and literature. Since Senefelder, experiments in lithography have continued with a range of innovations including the use of electron beams and UV that allow increasingly higher-resolution features [1, 2]. Applications for this have now breached the limits of paper printing into the realms of semiconductor and microelectronic mechanical systems technology. In this issue, researchers demonstrate a technique for fabricating periodic features in poly(3,4-ethylene dioxythiophene)-poly(styrenesulfonate) (PEDOT-PSS) [3]. Their method combines field enhancements from silica nanospheres with laser-interference lithography to provide a means of patterning a polymer that has the potential to open the market of low-end, high-volume microelectronics. Laser-interference lithography has already been used successfully in patterning. Researchers in Korea used laser-interference lithography to generate stamps for imprinting a two-dimensional photonic crystal structure into green light emitting diodes (LEDs) [4]. The imprinted patterns comprised depressions 100 nm deep and 180 nm wide with a periodicity of 295 nm. In comparison with unpatterned LEDs, the intensity of photoluminescence was enhanced by a factor of seven in the LEDs that had the photonic crystal structures imprinted in them. The potential of exploiting field enhancements around nanostructures for new technologies has also attracted a great deal of attention. Researchers in the USA and Australia have used the field

  4. Intra-individual comparison of different gadolinium-based contrast agents in the quantitative evaluation of C6 glioma with dynamic contrast-enhanced magnetic resonance imaging.

    Science.gov (United States)

    Li, Ying; Liu, Gang; Lou, Xin; Chen, Zhiye; Ma, Lin

    2017-01-01

    This experiment aimed to compare the ionic (Gadodiamide, Gd-DTPA-BMA) and non-ionic (Gadopentetate dimeglumine, Gd-DTPA) gadolinium-based contrast agents (GBCA) in the quantitative evaluation of C6 glioma with dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI). A C6 glioma model was established in 12 Wistar rats, and magnetic resonance (MR) scans were performed six days after tumor implantation. Imaging was performed using a 3.0-T MR scanner with a 7-inch handmade circular coil. Pre-contrast T1 mapping and dynamic contrast-enhanced T1WI after a bolus injection (0.2 mL s(-1)) of GBCA at 0.4 mmol kg(-1) were performed. Each rat received two DCE-MRI scans, 24 h apart. The first and second scans were performed using Gd-DTPA-BMA and Gd-DTPA, respectively. Image data were processed using the Patlak model. Both K (trans) and V p maps were generated. Tumors were manually segmented on all 3D K (trans) and V p maps. Pixel counts and mean values were recorded for use in a paired t-test. Three radiologists independently performed the tumor segmentation and value calculation. The agreements from different observers were subjective to the intra-class correlation coefficient (ICC). Readers demonstrated that the pixel counts of tumors in K (trans) maps were higher with Gd-DTPA-BMA than with Gd-DTPA (P0.05, all readers). The pixel counts of tumors in V p maps, as well as V p values, showed no obvious difference between the two agents (P>0.05, all readers). Excellent interobserver measurement reproducibility and reliability were demonstrated in the ICC tests. The Gd-DTPA-BMA contrast agent had significantly higher pixel counts of glioma in the K (trans) maps, and an increased tendency for average K (trans) values, indicating that DCE-MRI with Gd-DTPA-BMA may be more suitable and sensitive for the evaluation of glioma.

  5. Enhancement in Sport, and Enhancement outside Sport.

    Science.gov (United States)

    Douglas, Thomas

    2007-12-01

    Sport is one of the first areas in which enhancement has become commonplace. It is also one of the first areas in which the use of enhancement technologies has been heavily regulated. Some have thus seen sport as a testing ground for arguments about whether to permit enhancement. However, I argue that there are fairness-based objections to enhancement in sport that do not apply as strongly in some other areas of human activity. Thus, I claim that there will often be a stronger case for permitting enhancement outside of sport than for permitting enhancement in sport. I end by considering some methodological implications of this conclusion.

  6. Enhancement in Sport, and Enhancement outside Sport

    OpenAIRE

    Douglas, Thomas

    2007-01-01

    Sport is one of the first areas in which enhancement has become commonplace. It is also one of the first areas in which the use of enhancement technologies has been heavily regulated. Some have thus seen sport as a testing ground for arguments about whether to permit enhancement. However, I argue that there are fairness-based objections to enhancement in sport that do not apply as strongly in some other areas of human activity. Thus, I claim that there will often be a stronger case for permit...

  7. Justice, fairness, and enhancement.

    Science.gov (United States)

    Savulescu, Julian

    2006-12-01

    This article begins by considering four traditional definitions of enhancement, then proposes a fifth, the Welfarist definition. It then considers fairness-based objections to enhancement, using the example of performance enhancement in sport. In so doing it defines sport and the values proper to it, surveys alternative theories of justice, considers the natural distribution of capabilities and disabilities, and draws a distinction between social, psychological, and biological enhancement. The article advances a new argument that justice requires enhancement.

  8. Nephrogenic systemic fibrosis: change in incidence following a switch in gadolinium agents and adoption of a gadolinium policy--report from two U.S. universities.

    Science.gov (United States)

    Altun, Ersan; Martin, Diego R; Wertman, Rebecca; Lugo-Somolinos, Aida; Fuller, Edwin R; Semelka, Richard C

    2009-12-01

    To determine the incidence of nephrogenic systemic fibrosis (NSF) in tertiary care centers of two U.S. universities following the switch from the use of gadodiamide to gadobenate dimeglumine and gadopentetate dimeglumine, and the adoption of restrictive gadolinium-based contrast agent (GBCA) policies. Institutional review board approval with waiver of informed consent was obtained for this Health Insurance Portability and Accountability Act-compliant retrospective study. NSF patients were identified between January 2000 and December 2006 at center A and between October 2003 and February 2007 at center B (preadoption periods); and from June 2007 to June 2008 at both centers (postadoption period). The numbers of patients who underwent gadolinium-enhanced magnetic resonance at each center, patients at risk for NSF at center A, and dialysis patients at center B were identified in the pre- and postadoption periods. Gadodiamide was the only agent used in the preadoption period. Gadobenate dimeglumine and gadopentetate dimeglumine were the agents used in the postadoption period. A restrictive GBCA policy that limits the use and dose of GBCAs in patients with risk factors was adopted in the postadoption period. Follow-up lasted 9 months from July 2008 to March 2009. Corresponding incidences were determined and compared with the Fisher exact test. Respective total benchmark incidence of NSF at both centers, at-risk incidence of NSF at center A, and dialysis incidence of NSF at center B were 37 of 65 240, 28 of 925, and nine of 312 in the preadoption period and zero of 25 167, zero of 147, and zero of 402 in the postadoption period. All three incidences demonstrated significant differences (P < .0001, .024, and .001, respectively) between the pre- and postadoption periods. Following the switch from gadodiamide to gadobenate dimeglumine and gadopentetate dimeglumine, and the adoption of restrictive GBCA policies, no NSF cases were observed at either center.

  9. Oxygen-enhanced combustion

    CERN Document Server

    Baukal, Charles E

    2013-01-01

    Combustion technology has traditionally been dominated by air/fuel combustion. However, two developments have increased the significance of oxygen-enhanced combustion-new technologies that produce oxygen less expensively and the increased importance of environmental regulations. Advantages of oxygen-enhanced combustion include less pollutant emissions as well as increased energy efficiency and productivity. Oxygen-Enhanced Combustion, Second Edition compiles information about using oxygen to enhance industrial heating and melting processes. It integrates fundamental principles, applications, a

  10. Does breast MRI background parenchymal enhancement indicate metabolic activity? Qualitative and 3D quantitative computer imaging analysis.

    Science.gov (United States)

    Mema, Eralda; Mango, Victoria L; Guo, Xiaotao; Karcich, Jenika; Yeh, Randy; Wynn, Ralph T; Zhao, Binsheng; Ha, Richard S

    2017-06-24

    To investigate whether the degree of breast magnetic resonance imaging (MRI) background parenchymal enhancement (BPE) is associated with the amount of breast metabolic activity measured by breast parenchymal uptake (BPU) of 18F-FDG on positron emission tomography / computed tomography (PET/CT). An Institutional Review Board (IRB)-approved retrospective study was performed. Of 327 patients who underwent preoperative breast MRI from 1/1/12 to 12/31/15, 73 patients had 18F-FDG PET/CT evaluation performed within 1 week of breast MRI and no suspicious findings in the contralateral breast. MRI was performed on a 1.5T or 3.0T system. The imaging sequence included a triplane localizing sequence followed by sagittal fat-suppressed T2 -weighted sequence, and a bilateral sagittal T1 -weighted fat-suppressed fast spoiled gradient-echo sequence, which was performed before and three times after a rapid bolus injection (gadobenate dimeglumine, Multihance; Bracco Imaging; 0.1 mmol/kg) delivered through an IV catheter. The unaffected contralateral breast in these 73 patients underwent BPE and BPU assessments. For PET/CT BPU calculation, a 3D region of interest (ROI) was drawn around the glandular breast tissue and the maximum standardized uptake value (SUVmax ) was determined. Qualitative MRI BPE assessments were performed on a 4-point scale, in accordance with BI-RADS categories. Additional 3D quantitative MRI BPE analysis was performed using a previously published in-house technique. Spearman's correlation test and linear regression analysis was performed (SPSS, v. 24). The median time interval between breast MRI and 18F-FDG PET/CT evaluation was 3 days (range, 0-6 days). BPU SUVmax mean value was 1.6 (SD, 0.53). Minimum and maximum BPU SUVmax values were 0.71 and 4.0. The BPU SUVmax values significantly correlated with both the qualitative and quantitative measurements of BPE, respectively (r(71) = 0.59, P Qualitatively assessed high BPE group (BI-RADS 3/4) had significantly

  11. Intraparenchymal ultrasound application and improved distribution of infusate with convection-enhanced delivery in rodent and nonhuman primate brain.

    Science.gov (United States)

    Mano, Yui; Saito, Ryuta; Haga, Yoichi; Matsunaga, Tadao; Zhang, Rong; Chonan, Masashi; Haryu, Shinya; Shoji, Takuhiro; Sato, Aya; Sonoda, Yukihiko; Tsuruoka, Noriko; Nishiyachi, Keisuke; Sumiyoshi, Akira; Nonaka, Hiroi; Kawashima, Ryuta; Tominaga, Teiji

    2016-05-01

    OBJECT Convection-enhanced delivery (CED) is an effective drug delivery method that delivers high concentrations of drugs directly into the targeted lesion beyond the blood-brain barrier. However, the drug distribution attained using CED has not satisfactorily covered the entire targeted lesion in tumors such as glioma. Recently, the efficacy of ultrasound assistance was reported for various drug delivery applications. The authors developed a new ultrasound-facilitated drug delivery (UFD) system that enables the application of ultrasound at the infusion site. The purpose of this study was to demonstrate the efficacy of the UFD system and to examine effective ultrasound profiles. METHODS The authors fabricated a steel bar-based device that generates ultrasound and enables infusion of the aqueous drug from one end of the bar. The volume of distribution (Vd) after infusion of 10 ml of 2% Evans blue dye (EBD) into rodent brain was tested with different frequencies and applied voltages: 252 kHz/30 V; 252 kHz/60 V; 524 kHz/13 V; 524 kHz/30 V; and 524 kHz/60 V. In addition, infusion of 5 mM gadopentetate dimeglumine (Gd-DTPA) was tested with 260 kHz/60 V, the distribution of which was evaluated using a 7-T MRI unit. In a nonhuman primate (Macaca fascicularis) study, 300 μl of 1 mM Gd-DTPA/EBD was infused. The final distribution was evaluated using MRI. Two-sample comparisons were made by Student t-test, and 1-way ANOVA was used for multiple comparisons. Significance was set at p < 0.05. RESULTS After infusion of 10 μl of EBD into the rat brain using the UFD system, the Vds of EBD in the UFD groups were significantly larger than those of the control group. When a frequency of 252 kHz was applied, the Vd of the group in which 60 V was applied was significantly larger than that of the group in which 30 V was used. When a frequency of 524 kHz was applied, the Vd tended to increase with application of a higher voltage; however, the differences were not significant (1-way

  12. Clinical phase II study with Gd-DTPA (dimeglumine gadopentetate, SHL 451 A) in brain tumor and cerebral infarction

    Energy Technology Data Exchange (ETDEWEB)

    Yoshikawa, Kohki; Aoki, Shigeki; Machida, Tohru and others

    1988-06-01

    A clinical phase II study with Gd-DTPA, the first contrast medium for MRI, was performed in 109 cases, a total of 114 studies mainly with brain tumor. In this study, one of the three concentrations of Gd-DTPA, 0.05 mmol/kg, 0.10 mmol/kg or 0.15 mmol/kg was used in each patient. It was elucidated that especially 0.10 and 0.15 Gd-DTPA were useful in detecting disruption or abscence of BBB and distinguishing tumor from edema. The side-effect observed was only a slight urticaria which was seen with 0.15 mmol/kg Gd-DTPA. Accordingly, it was estimated that the standard concentration of Gd-DTPA would be 0.10 mmol/kg. As this contrast medium was safe, and clinically useful in detecting diseases of the central nervous system, it was concluded that the shift to the clinical phase III trial is possible.

  13. Smart Image Enhancement Process

    Science.gov (United States)

    Jobson, Daniel J. (Inventor); Rahman, Zia-ur (Inventor); Woodell, Glenn A. (Inventor)

    2012-01-01

    Contrast and lightness measures are used to first classify the image as being one of non-turbid and turbid. If turbid, the original image is enhanced to generate a first enhanced image. If non-turbid, the original image is classified in terms of a merged contrast/lightness score based on the contrast and lightness measures. The non-turbid image is enhanced to generate a second enhanced image when a poor contrast/lightness score is associated therewith. When the second enhanced image has a poor contrast/lightness score associated therewith, this image is enhanced to generate a third enhanced image. A sharpness measure is computed for one image that is selected from (i) the non-turbid image, (ii) the first enhanced image, (iii) the second enhanced image when a good contrast/lightness score is associated therewith, and (iv) the third enhanced image. If the selected image is not-sharp, it is sharpened to generate a sharpened image. The final image is selected from the selected image and the sharpened image.

  14. Enhancing human capacities

    CERN Document Server

    Savulescu, Julian; Kahane, Guy

    2011-01-01

    Enhancing Human Capacities is the first to review the very latest scientific developments in human enhancement. It is unique in its examination of the ethical and policy implications of these technologies from a broad range of perspectives. Presents a rich range of perspectives on enhancement from world leading ethicists and scientists from Europe and North America The most comprehensive volume yet on the science and ethics of human enhancement Unique in providing a detailed overview of current and expected scientific advances in this area Discusses both general conceptual and ethical issues

  15. Contrast enhanced cartilage imaging: Comparison of ionic and non-ionic contrast agents

    Energy Technology Data Exchange (ETDEWEB)

    Wiener, Edzard [Department of Radiology, Technical University Munich, Ismaninger Str. 22, D-81675 Munich (Germany)]. E-mail: ewiener@roe.med.tu-muenchen.de; Woertler, Klaus [Department of Radiology, Technical University Munich, Ismaninger Str. 22, D-81675 Munich (Germany); Weirich, Gregor [Institute of Pathology, Technical University Munich, Troger Str. 18, D-81675 Munich (Germany); Rummeny, Ernst J. [Department of Radiology, Technical University Munich, Ismaninger Str. 22, D-81675 Munich (Germany); Settles, Marcus [Department of Radiology, Technical University Munich, Ismaninger Str. 22, D-81675 Munich (Germany)

    2007-07-15

    Our objective was to compare relaxation effects, dynamics and spatial distributions of ionic and non-ionic contrast agents in articular cartilage at concentrations typically used for direct MR arthrography at 1.5 T. Dynamic MR-studies over 11 h were performed in 15 bovine patella specimens. For each of the contrast agents gadopentetate dimeglumine, gadobenate dimeglumine, gadoteridol and mangafodipir trinatrium three patellae were placed in 2.5 mmol/L contrast solution. Simultaneous measurements of T {sub 1} and T {sub 2} were performed every 30 min using a high-spatial-resolution 'MIX'-sequence. T {sub 1}, T {sub 2} and {delta}R {sub 1}, {delta}R {sub 2} profile plots across cartilage thickness were calculated to demonstrate the spatial and temporal distributions. The charge is one of the main factors which controls the amount of the contrast media diffusing into intact cartilage, but independent of the charge, the spatial distribution across cartilage thickness remains highly inhomogeneous even after 11 h of diffusion. The absolute {delta}R {sub 2}-effect in cartilage is at least as large as the {delta}R {sub 1}-effect for all contrast agents. Maximum changes were 5-12 s{sup -1} for {delta}R {sub 1} and 8-15 s{sup -1} for {delta}R {sub 2}. This study indicates that for morphologically intact cartilage only the amount of contrast agents within cartilage is determined by the charge but not the spatial distribution across cartilage thickness. In addition, {delta}R {sub 2} can be considered for quantification of contrast agent concentrations, since it is of the same magnitude and less time consuming to measure than {delta}R {sub 1}.

  16. Enhanced superconductivity of fullerenes

    Energy Technology Data Exchange (ETDEWEB)

    Washington, II, Aaron L.; Teprovich, Joseph A.; Zidan, Ragaiy

    2017-06-20

    Methods for enhancing characteristics of superconductive fullerenes and devices incorporating the fullerenes are disclosed. Enhancements can include increase in the critical transition temperature at a constant magnetic field; the existence of a superconducting hysteresis over a changing magnetic field; a decrease in the stabilizing magnetic field required for the onset of superconductivity; and/or an increase in the stability of superconductivity over a large magnetic field. The enhancements can be brought about by transmitting electromagnetic radiation to the superconductive fullerene such that the electromagnetic radiation impinges on the fullerene with an energy that is greater than the band gap of the fullerene.

  17. Personal Identity in Enhancement

    Directory of Open Access Journals (Sweden)

    Jana Podroužková

    2015-09-01

    Full Text Available The aim of this paper is to introduce the concept of human enhancement, its methods and its relation to personal identity. Also several approaches to personal identity will be described. Transhumanism is a special think tank supporting human enhancement through modern technologies and some of its representatives claim, that even great changes to human organisms will not affect their personal identity. I will briefly describe the most important means of human enhancment and consider the problem of personal identity for each of them separately.

  18. Enhanced Magnetic Model 2015

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The Enhanced Magnetic Model (EMM) extends to degree and order 720, resolving magnetic anomalies down to 56 km wavelength. The higher resolution of the EMM results in...

  19. Technology Enhanced Learning

    NARCIS (Netherlands)

    Klemke, Roland; Specht, Marcus

    2013-01-01

    Klemke, R., & Specht, M. (2013, 26-27 September). Technology Enhanced Learning. Presentation at the fourth international conference on eLearning (eLearning 2013), Belgrade, Serbia. http://econference.metropolitan.ac.rs/

  20. Ogallala Bedrock Data Enhancement

    Data.gov (United States)

    Kansas Data Access and Support Center — This data set provides an enhanced estimate of the bedrock elevation of the Ogallala Aquifer in Kansas based on lithologic logs from a variety of sources. The data...

  1. Enhanced Magnetic Model 2010

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The Enhanced Magnetic Model (EMM) extends to degree and order 720, resolving magnetic anomalies down to 56 km wavelength. The higher resolution of the EMM results in...

  2. Canonical Strangeness Enhancement

    CERN Document Server

    Sollfrank, J; Redlich, Krzysztof; Satz, Helmut

    1998-01-01

    According to recent experimental data and theoretical developments we discuss three distinct topics related to strangeness enhancement in nuclear reactions. We investigate the compatibility of multi-strange particle ratios measured in a restricted phase space with thermal model parameters extracted recently in 4pi. We study the canonical suppression as a possible reason for the observed strangeness enhancement and argue that a connection between QGP formation and the undersaturation of strangeness is not excluded.

  3. Resonance Enhanced Tunneling

    CERN Document Server

    Matsumoto, S; Matsumoto, Sh.

    2000-01-01

    Time evolution of tunneling in thermal medium is examined using the real-time semiclassical formalism previously developed. Effect of anharmonic terms in the potential well is shown to give a new mechanism of resonance enhanced tunneling. If the friction from environment is small enough, this mechanism may give a very large enhancement for the tunneling rate. The case of the asymmetric wine bottle potential is worked out in detail.

  4. Enhanced metabolite generation

    Science.gov (United States)

    Chidambaram, Devicharan [Middle Island, NY

    2012-03-27

    The present invention relates to the enhanced production of metabolites by a process whereby a carbon source is oxidized with a fermentative microbe in a compartment having a portal. An electron acceptor is added to the compartment to assist the microbe in the removal of excess electrons. The electron acceptor accepts electrons from the microbe after oxidation of the carbon source. Other transfers of electrons can take place to enhance the production of the metabolite, such as acids, biofuels or brewed beverages.

  5. E-nhance Lectures

    OpenAIRE

    Naber, Larissa; Köhle, Monika

    2006-01-01

    Ever more lecturers find themselves forced to Web-enhance their courses out of economic pressure or prestige. Universities trapped between rising student numbers and decreasing budgets are turning to e-learning as the one-stop solution, with little concern for student or teacher needs. An e-(nhanced) learning environment can only be successful if it fulfils students' and lecturers' needs alike. The student needs to be supported in various stages of learning, whereas the lecturer cannot afford...

  6. Transform image enhancement

    Science.gov (United States)

    Aghagolzadeh, Sabzali; Ersoy, Okan K.

    1992-03-01

    Blockwise transform image enhancement techniques are discussed. Previously, transform image enhancement has usually been based on the discrete Fourier transform (DFT) applied to the whole image. Two major drawbacks with the DFT are high complexity of implementation involving complex multiplications and additions, with intermediate results being complex numbers, and the creation of severe block effects if image enhancement is done blockwise. In addition, the quality of enhancement is not very satisfactory. It is shown that the best transforms for transform image coding, namely, the scrambled real discrete Fourier transform, the discrete cosine transform, and the discrete cosine-III transform, are also the best for image enhancement. Three techniques of enhancement discussed in detail are alpha- rooting, modified unsharp masking, and filtering motivated by the human visual system response (HVS). With proper modifications, it is observed that unsharp masking and HVS- motivated filtering without nonlinearities are basically equivalent. Block effects are completely removed by using an overlap-save technique in addition to the best transform.

  7. Magnetic resonance imaging of liver metastases: experimental comparison of anionic and conventional superparamagnetic iron oxide particles with a hepatobiliary contrast medium during dynamic and uptake phases.

    Science.gov (United States)

    Kaufels, Nicola; Korn, Ronny; Wagner, Susanne; Schink, Tania; Hamm, Bernd; Taupitz, Matthias; Schnorr, Jörg

    2008-07-01

    To assess the contrast-enhancing effects of citrate-coated superparamagnetic iron oxide particles (VSOP-C184) in a rat liver tumor model using dynamic and delayed magnetic resonance imaging in comparison to carboxydextran-coated particles (ferucarbotran) and a hepatobiliary contrast medium (gadobenate dimeglumine). A total of 32 male rats with liver tumors (CC-531 colorectal carcinoma) were examined at 1.5 T with a T1-weighted dynamic series (3D gradient echo sequence) and T1-weighted and T2*-weighted images (2D gradient echo sequences) before and 15 and 90 minutes after injection. VSOP-C184 was investigated at doses of 0.015, 0.045, and 0.06 mmol Fe/kg, ferucarbotran at 0.015 mmol Fe/kg, and gadobenate dimeglumine at 0.025, 0.05, and 0.1 mmol Gd/kg. Liver-tumor contrast-to-noise ratio (CNR) was calculated and statistically compared. T1-weighted dynamic images: VSOP-C184 has significantly higher CNR values at a dose of 0,015 mmol Fe/kg than ferucarbotran at the same dose (P = 0.001). VSOP-C184 produces a significantly higher CNR at a dose of 0.045 mmol Fe/kg than gadobenate dimeglumine at a dose of 0.05 mmol Gd/kg (P = 0.019). At a dose of 0.06 mmol Fe/kg, the CNR for VSOP-C184 is significantly lower than that of gadobenate dimeglumine (0.1 mmol Gd/kg) (P = 0.005).T2-weighted delayed images: CNR values of VSOP-C184 are similar to those of ferucarbotran and are significantly higher than those of gadobenate dimeglumine (P VSOP-C184 produces a high contrast comparable to that of a hepatobiliary contrast medium in addition to its contrast-enhancing effect in T2-weighted imaging.

  8. Enhancer networks revealed by correlated DNAse hypersensitivity states of enhancers.

    Science.gov (United States)

    Malin, Justin; Aniba, Mohamed Radhouane; Hannenhalli, Sridhar

    2013-08-01

    Mammalian gene expression is often regulated by distal enhancers. However, little is known about higher order functional organization of enhancers. Using ∼100 K P300-bound regions as candidate enhancers, we investigated their correlated activity across 72 cell types based on DNAse hypersensitivity. We found widespread correlated activity between enhancers, which decreases with increasing inter-enhancer genomic distance. We found that correlated enhancers tend to share common transcription factor (TF) binding motifs, and several chromatin modification enzymes preferentially interact with these TFs. Presence of shared motifs in enhancer pairs can predict correlated activity with 73% accuracy. Also, genes near correlated enhancers exhibit correlated expression and share common function. Correlated enhancers tend to be spatially proximal. Interestingly, weak enhancers tend to correlate with significantly greater numbers of other enhancers relative to strong enhancers. Furthermore, strong/weak enhancers preferentially correlate with strong/weak enhancers, respectively. We constructed enhancer networks based on shared motif and correlated activity and show significant functional enrichment in their putative target gene clusters. Overall, our analyses show extensive correlated activity among enhancers and reveal clusters of enhancers whose activities are coordinately regulated by multiple potential mechanisms involving shared TF binding, chromatin modifying enzymes and 3D chromatin structure, which ultimately co-regulate functionally linked genes.

  9. Human nature and enhancement.

    Science.gov (United States)

    Buchanan, Allen

    2009-03-01

    Appeals to the idea of human nature are frequent in the voluminous literature on the ethics of enhancing human beings through biotechnology. Two chief concerns about the impact of enhancements on human nature have been voiced. The first is that enhancement may alter or destroy human nature. The second is that if enhancement alters or destroys human nature, this will undercut our ability to ascertain the good because, for us, the good is determined by our nature. The first concern assumes that altering or destroying human nature is in itself a bad thing. The second concern assumes that human nature provides a standard without which we cannot make coherent, defensible judgments about what is good. I will argue (1) that there is nothing wrong, per se, with altering or destroying human nature, because, on a plausible understanding of what human nature is, it contains bad as well as good characteristics and there is no reason to believe that eliminating some of the bad would so imperil the good as to make the elimination of the bad impermissible, and (2) that altering or destroying human nature need not result in the loss of our ability to make judgments about the good, because we possess a conception of the good by which we can and do evaluate human nature. I will argue that appeals to human nature tend to obscure rather than illuminate the debate over the ethics of enhancement and can be eliminated in favor of more cogent considerations.

  10. Enhanced nurse call systems.

    Science.gov (United States)

    2001-04-01

    This Evaluation focuses on high-end computerized nurse call systems--what we call enhanced systems. These are highly flexible systems that incorporate microprocessor and communications technologies to expand the capabilities of the nurse call function. Enhanced systems, which vary in configuration from one installation to the next, typically consist of a basic system that provides standard nurse call functionality and a combination of additional enhancements that provide the added functionality the facility desires. In this study, we examine the features that distinguish enhanced nurse call systems from nonenhanced systems, focusing on their application and benefit to healthcare facilities. We evaluated seven systems to determine how well they help (1) improve patient care, as well as increase satisfaction with the care provided, and (2) improve caregiver efficiency, as well as increase satisfaction with the work environment. We found that all systems meet these objectives, but not all systems perform equally well for all implementations. Our ratings will help facilities identify those systems that offer the most effective features for their intended use. The study also includes a Technology Management Guide to help readers (1) determine whether they'll benefit from the capabilities offered by enhanced systems and (2) target a system for purchase and equip the system for optimum performance and cost-effective operation.

  11. Christian Self-Enhancement.

    Science.gov (United States)

    Gebauer, Jochen E; Sedikides, Constantine; Schrade, Alexandra

    2017-02-16

    People overestimate themselves in domains that are central to their self-concept. Critically, the psychological status of this "self-centrality principle" remains unclear. One view regards the principle as an inextricable part of human nature and, thus, as universal and resistant to normative pressure. A contrasting view regards the principle as liable to pressure (and subsequent modification) from self-effacement norms, thus questioning its universality. Advocates of the latter view point to Christianity's robust self-effacement norms, which they consider particularly effective in curbing self-enhancement, and ascribe Christianity an ego-quieting function. Three sets of studies examined the self-centrality principle among Christians. Studies 1A and 1B (N = 2,118) operationalized self-enhancement as better-than-average perceptions on the domains of commandments of faith (self-centrality: Christians ≫ nonbelievers) and commandments of communion (self-centrality: Christians > nonbelievers). Studies 2A-2H (N = 1,779) operationalized self-enhancement as knowledge overclaiming on the domains of Christianity (self-centrality: Christians ≫ nonbelievers), communion (self-centrality: Christians > nonbelievers), and agency (self-centrality: Christians ≈ nonbelievers). Studies 3A-3J (N = 1,956) operationalized self-enhancement as grandiose narcissism on the domains of communion (self-centrality: Christians > nonbelievers) and agency (self-centrality: Christians ≈ nonbelievers). The results converged across studies, yielding consistent evidence for Christian self-enhancement. Relative to nonbelievers, Christians self-enhanced strongly in domains central to the Christian self-concept. The results also generalized across countries with differing levels of religiosity. Christianity does not quiet the ego. The self-centrality principle is resistant to normative pressure, universal, and rooted in human nature. (PsycINFO Database Record

  12. Cavity-enhanced spectroscopies

    CERN Document Server

    van Zee, Roger

    2003-01-01

    ""Cavity-Enhanced Spectroscopy"" discusses the use of optical resonators and lasers to make sensitive spectroscopic measurements. This volume is written by the researcchers who pioneered these methods. The book reviews both the theory and practice behind these spectroscopic tools and discusses the scientific discoveries uncovered by these techniques. It begins with a chapter on the use of optical resonators for frequency stabilization of lasers, which is followed by in-depth chapters discussing cavity ring-down spectroscopy, frequency-modulated, cavity-enhanced spectroscopy, intracavity spectr

  13. Enhanced Piezoelectric Shunt Design

    Directory of Open Access Journals (Sweden)

    Chul H. Park

    2003-01-01

    Full Text Available Piezoceramic material connected to an electronic shunt branch circuit has formed a successful vibration reduction device. One drawback of the conventional electronic shunt circuit is the large inductance required when suppressing low frequency vibration modes. Also, the large internal resistance associated with this large inductance exceeds the optimal design resistance needed for low frequency vibration suppression. To solve this problem, a modified and enhanced piezoelectric shunt circuit is designed and analyzed by using mechanical-electrical analogies to present the physical interpretation. The enhanced shunt circuit developed in this paper is proved to significantly reduce the targeted vibration mode of a cantilever beam, theoretically and experimentally.

  14. Biomedical enhancements as justice.

    Science.gov (United States)

    Nam, Jeesoo

    2015-02-01

    Biomedical enhancements, the applications of medical technology to make better those who are neither ill nor deficient, have made great strides in the past few decades. Using Amartya Sen's capability approach as my framework, I argue in this article that far from being simply permissible, we have a prima facie moral obligation to use these new developments for the end goal of promoting social justice. In terms of both range and magnitude, the use of biomedical enhancements will mark a radical advance in how we compensate the most disadvantaged members of society.

  15. Teaching to Enhance Research

    Science.gov (United States)

    Harland, Tony

    2016-01-01

    In this paper, I present a conceptual argument for "teaching-led research" in which university lecturers construct courses that directly and positively influence their research, while at the same time, safeguard and enhance the student experience. A research-pedagogy for higher education considers the link between teaching and research,…

  16. Simulations of Enhanced Confinement

    Science.gov (United States)

    Dorland, W.; Kotschenreuther, M.; Liu, Q. P.; Jones, C. S.; Beer, M. A.; Hammett, G. W.

    1996-11-01

    Most existing tokamaks routinely achieve enhanced confinement regimes. Designs for new, larger tokamaks therefore are typically predicated upon reliable enhanced confinement performance. However, most enhanced confinement regimes rely (to some degree) upon sheared E×B flows to stabilize the turbulence that otherwise limits the confinement. For example, the pedestal H-mode transport barrier is typically attributed to shear stabilization [Biglari, Diamond and Terry, Phys. Fl. B, 2 1 (1990)]. Unfortunately, it is easily shown that sheared E×B stabilization of microinstabilities such as the ITG mode does not scale favorably with machine size. Here, using nonlinear gyrofluid simulations in general geometry, we attempt to quantify the confinement enhancement that can be expected from velocity shear stabilization for conventional reactor plasmas. We also consider other microinstability stabilization mechanisms(See related presentations by Beer, Kotschenreuther, Manickam, and Ramos, this conference.) (strong density peaking, Shafranov shift stabilization, dots) and unconventional reactor configurations.^2 Experimental datasets from JET, DIII-D, C-Mod and TFTR are analyzed, and ITER operation is considered.

  17. Enhanced processive cellulases

    Energy Technology Data Exchange (ETDEWEB)

    Adney, William S.; Beckham, Gregg T.; Jarvis, Eric; Himmel, Michael E.; Decker, Stephen R.; Linger, Jeffrey G.; Podkaminer, Kara; Baker, John O.; Taylor, II, Larry; Xu, Qi; Singh, Arjun

    2017-06-20

    Nucleic acid sequences encoding chimeric polypeptides that exhibit enhanced cellulase activities are disclosed herein. These nucleic acids may be expressed in hosts such as fungi, which in turn may be cultured to produce chimeric polypeptides. Also disclosed are chimeric polypeptides and their use in the degradation of cellulosic materials.

  18. Enhanced Optical Filter Design

    CERN Document Server

    Cushing, David

    2011-01-01

    This book serves as a supplement to the classic texts by Angus Macleod and Philip Baumeister, taking an intuitive approach to the enhancement of optical coating (or filter) performance. Drawing from 40 years of experience in thin film design, Cushing introduces the basics of thin films, the commonly used materials and their deposition, the major coatings and their applications, and improvement methods for each.

  19. Music Enhances Learning.

    Science.gov (United States)

    Campabello, Nicolette; De Carlo, Mary Jane; O'Neil, Jean; Vacek, Mary Jill

    An action research project implemented musical strategies to affect and enhance student recall and memory. The target population was three suburban elementary schools near a major midwestern city: (1) a kindergarten classroom contained 32-38 students; (2) a second grade classroom contained 23 students and five Individualized Education Program…

  20. Competence Enhancement Behavior Management

    Science.gov (United States)

    Farmer, Thomas W.; Goforth, Jennifer B.; Hives, Jacqueline; Aaron, Annie; Jackson, Frances; Sgammato, Adrienne

    2006-01-01

    Competence Enhancement Behavior Management is presented as a framework for supporting students with challenging behaviors in general education classrooms. This approach emphasizes classroom management and discipline strategies that (a) help to build positive relations with students, (b) communicate to students that they are important, and (c)…

  1. Enhanced Attenuation: Chlorinated Organics

    Science.gov (United States)

    2008-04-01

    three sites, and lactate, whey powder, barometric pumping, and nutrient- enhanced biosparging at one site each. Full-scale applications were reported... applicable health and safety risks and precautions with respect to particular materials, conditions, or procedures in specific applications of any technology...Consequently, ITRC recommends also consulting applicable standards, laws, regulations, suppliers of materials, and material safety data sheets for

  2. Measuring and Enhancing Creativity

    Science.gov (United States)

    Mahboub, Kamyar C.; Portillo, Margaret B.; Liu, Yinhui; Chandraratna, Susantha

    2004-01-01

    The purpose of this study was to assess ways by which creativity may be enhanced in a design-oriented course. In order to demonstrate the validity of the approach, a statistically based study was employed. Additionally, the experiment was replicated in two design-oriented fields at the University of Kentucky. These fields were civil engineering…

  3. Enhancing learning with technology

    NARCIS (Netherlands)

    Specht, Marcus; Klemke, Roland

    2013-01-01

    Specht, M., & Klemke, R. (2013, 26-27 September). Enhancing Learning with Technology. In D. Milosevic (Ed.), Proceedings of the fourth international conference on eLearning (eLearning 2013) (pp. 37-45). Belgrade Metropolitan University, Belgrade, Serbia. http://econference.metropolitan.ac.rs/

  4. Wedgelet Enhanced Appearance Models

    DEFF Research Database (Denmark)

    Darkner, Sune; Larsen, Rasmus; Stegmann, Mikkel Bille;

    2004-01-01

    . The wedgelet regression trees employed are based on triangular domains and estimated using cross validation. The wedgelet regression trees are functional descriptions of the intensity information and serve to 1) reduce noise and 2) produce a compact textural description. The wedgelet enhanced appearance model...

  5. Teaching to Enhance Research

    Science.gov (United States)

    Harland, Tony

    2016-01-01

    In this paper, I present a conceptual argument for "teaching-led research" in which university lecturers construct courses that directly and positively influence their research, while at the same time, safeguard and enhance the student experience. A research-pedagogy for higher education considers the link between teaching and research,…

  6. Piezoelectrically Enhanced Photocathodes

    Science.gov (United States)

    Beach, Robert A.; Nikzad, Shouleh; Bell, Lloyd Douglas; Strittmatter, Robert

    2011-01-01

    Doping of photocathodes with materials that have large piezoelectric coefficients has been proposed as an alternative means of increasing the desired photoemission of electrons. Treating cathode materials to increase emission of electrons is called "activation" in the art. It has been common practice to activate photocathodes by depositing thin layers of suitable metals (usually, cesium). Because cesium is unstable in air, fabrication of cesiated photocathodes and devices that contain them must be performed in sealed tubes under vacuum. It is difficult and costly to perform fabrication processes in enclosed, evacuated spaces. The proposed piezoelectrically enhanced photocathodes would have electron-emission properties similar to those of cesiated photocathodes but would be stable in air, and therefore could be fabricated more easily and at lower cost. Candidate photocathodes include nitrides of elements in column III of the periodic table . especially compounds of the general formula Al(x)Ga(1.x)N (where 0< or = x < or =.1). These compounds have high piezoelectric coefficients and are suitable for obtaining response to ultraviolet light. Fabrication of a photocathode according to the proposal would include inducement of strain in cathode layers during growth of the layers on a substrate. The strain would be induced by exploiting structural mismatches among the various constituent materials of the cathode. Because of the piezoelectric effect in this material, the strain would give rise to strong electric fields that, in turn, would give rise to a high concentration of charge near the surface. Examples of devices in which piezoelectrically enhanced photocathodes could be used include microchannel plates, electron- bombarded charge-coupled devices, image tubes, and night-vision goggles. Piezoelectrically enhanced photocathode materials could also be used in making highly efficient monolithic photodetectors. Highly efficient and stable piezoelectrically enhanced

  7. Contrast-enhanced breast MR imaging of claustrophobic or oversized patients using an open low-field magnet.

    Science.gov (United States)

    Calabrese, M; Brizzi, D; Carbonaro, L; Chiaramondia, M; Kirchin, M A; Sardanelli, F

    2009-03-01

    A number of women who should undergo magnetic resonance (MR) imaging of the breast cannot use this diagnostic tool due to claustrophobia or excessive body size for the restricted confines of standard closed MR systems. Our aim was to evaluate the performance of open low-field magnet breast MR imaging in such patients using a high-relaxivity contrast agent. Of 397 consecutive patients undergoing breast MR imaging, 379 (95.5%) were studied at 1.5 T. Due to claustrophobia (n=15) or large body size (n=3), 18 patients (4.5%) were studied on a 0.2-T open magnet using a body coil. A 3D dynamic T1-weighted gradient-echo 94-s sequence was acquired with intravenous injection of gadobenate dimeglumine (0.1 mmol/kg). The standard of reference was pathological examination for 16 lesions classified with a maximal Breast Imaging Reporting and Data System (BI-RADS) score from 3 to 5, fine-needle aspiration cytology and >or=2-year follow-up for two lesions classified as BI-RADS 3, and >or=2-years follow-up for five lesions classified as BI-RADS 2. Diagnostic MR image quality was achieved for 20/23 lesions in 15/18 patients. Three lesions (two invasive cancers and a cyst) were not assessed due to patient movement and considered as two false negatives and one false positive. Thus, an 86% sensitivity [13/15; 95% confidence interval (CI): 70%-100%], an 87% specificity (7/8; 95% CI: 65%-100%) and an 87% accuracy (20/23; 95% CI: 73%-100%) were obtained. The intraclass correlation coefficient between MR and pathologic lesion size was 0.845. In claustrophobic or oversized patients, open low-field breast MR with gadobenate dimeglumine yields good diagnostic performance.

  8. Superposition Enhanced Nested Sampling

    Directory of Open Access Journals (Sweden)

    Stefano Martiniani

    2014-08-01

    Full Text Available The theoretical analysis of many problems in physics, astronomy, and applied mathematics requires an efficient numerical exploration of multimodal parameter spaces that exhibit broken ergodicity. Monte Carlo methods are widely used to deal with these classes of problems, but such simulations suffer from a ubiquitous sampling problem: The probability of sampling a particular state is proportional to its entropic weight. Devising an algorithm capable of sampling efficiently the full phase space is a long-standing problem. Here, we report a new hybrid method for the exploration of multimodal parameter spaces exhibiting broken ergodicity. Superposition enhanced nested sampling combines the strengths of global optimization with the unbiased or athermal sampling of nested sampling, greatly enhancing its efficiency with no additional parameters. We report extensive tests of this new approach for atomic clusters that are known to have energy landscapes for which conventional sampling schemes suffer from broken ergodicity. We also introduce a novel parallelization algorithm for nested sampling.

  9. Enhanced magnetocaloric effect material

    Science.gov (United States)

    Lewis, Laura J. H.

    2006-07-18

    A magnetocaloric effect heterostructure having a core layer of a magnetostructural material with a giant magnetocaloric effect having a magnetic transition temperature equal to or greater than 150 K, and a constricting material layer coated on at least one surface of the magnetocaloric material core layer. The constricting material layer may enhance the magnetocaloric effect by restriction of volume changes of the core layer during application of a magnetic field to the heterostructure. A magnetocaloric effect heterostructure powder comprising a plurality of core particles of a magnetostructural material with a giant magnetocaloric effect having a magnetic transition temperature equal to or greater than 150 K, wherein each of the core particles is encapsulated within a coating of a constricting material is also disclosed. A method for enhancing the magnetocaloric effect within a giant magnetocaloric material including the step of coating a surface of the magnetocaloric material with a constricting material is disclosed.

  10. Enhanced oil recovery

    Energy Technology Data Exchange (ETDEWEB)

    Chakma, A.; Rafiq Islam, M.; Berruti, F.

    1991-01-01

    Some forty to sixty percent of the original oil in place typically remains trapped in the reservoir after primary and secondary recoveries. Enhanced oil recovery refers to the recovery of the residual oil by different techniques. Many of the existing and proposed enhanced oil recovery techniques require sound understanding of basic chemical engineering principles such as fluid flow, heat and mass transfer, interfacial phenomena etc. Chemical EOR techniques require a good understanding of interfacial phenomena, chemical reaction, multicomponent absorption. Understanding of the fundamentals of the various EOR processes is not adequate. EOR is increasingly attracting a growing number of chemical engineers and, as a result, some of the fundamental aspect of EOR are now being investigated. However, much more remains to be done and chemical engineers can play an important role in providing a better understanding of EOR fundamentals. This volume presents selected papers on EOR presented at AICHE meetings.

  11. Vibration enhanced quantum transport

    CERN Document Server

    Semião, F L; Milburn, G J

    2009-01-01

    In this paper, we study the role of a collective vibrational motion in the phenomenon of electronic energy transfer (EET) between chromophores with different electronic transition frequencies. Previous experimental work on EET in conjugated polymer samples has suggested that the common structural framework of the macromolecule introduce correlations in the energy gap fluctuations which cause coherent EET. We present a simple model describing the coupling between the chromophores and a common vibrational mode, and find that vibration can indeed lead to an enhancement in the transport of excitations across the quantum network. Furthermore, in our model phase information is partially retained in the transfer process from a donor to an acceptor, as experimentally demonstrated in the conjugated polymer system. Consequently, this mechanism of vibration enhanced quantum transport might find applications in quantum information transfer of qubit states or entanglement.

  12. Coherence-Enhanced Spaser

    CERN Document Server

    Dorfman, Konstantin E; Voronine, Dmitri V; Genevet, Patrice; Capasso, Federico; Scully, Marlan O

    2012-01-01

    We investigate surface plasmon amplification in a silver nanoshell coupled to an externally driven three-level gain medium, and show that quantum coherence significantly enhances the generation of surface plasmons. Surface plasmon amplification by stimulated emission of radiation is achieved in the absence of population inversion on the spasing transition, which reduces the pump requirements. The coherent drive allows us to control the dynamics, and holds promise for quantum control of nanoplasmonic devices.

  13. Light enhances learned fear.

    Science.gov (United States)

    Warthen, Daniel M; Wiltgen, Brian J; Provencio, Ignacio

    2011-08-16

    The ability to learn, remember, and respond to emotional events is a powerful survival strategy. However, dysregulated behavioral and physiological responses to these memories are maladaptive. To fully understand learned fear and the pathologies that arise during response malfunction we must reveal the environmental variables that influence learned fear responses. Light, a ubiquitous environmental feature, modulates cognition and anxiety. We hypothesized that light modulates responses to learned fear. Using tone-cued fear conditioning, we found that light enhances behavioral responses to learned fear in C57BL/6J mice. Mice in light freeze more in response to a conditioned cue than mice in darkness. The absence of significant freezing during a 2-wk habituation period and during intertrial intervals indicated that light specifically modulates freezing to the learned acoustic cue rather than the context of the experimental chamber. Repeating our assay in two photoreceptor mutant models, Pde6b(rd1/rd1) and Opn4(-/-) mice, revealed that light-dependent enhancement of conditioned fear is driven primarily by the rods and/or cones. By repeating our protocol with an altered lighting regimen, we found that lighting conditions acutely modulate responses when altered between conditioning and testing. This is manifested either as an enhancement of freezing when light is added during testing or as a depression of freezing when light is removed during testing. Acute enhancement, but not depression, requires both rod/cone- and melanopsin-dependent photoreception. Our results demonstrate a modulation by light of behavioral responses to learned fear.

  14. Beyond enhanced recovery?

    DEFF Research Database (Denmark)

    Jørgensen, Christoffer C; Kehlet, Henrik

    2014-01-01

    We read with great interest the special article by Smart and Daniels discussing several important topics of perioperative care, especially regarding lack of consensus on the definition of "postoperative recovery", and need for further understanding of the pathogenic mechanisms. However, we disagr...... that a "new, clearly defined standard of what "recovery" actually is", demands "a look beyond enhanced recovery"(1) for several reasons. This article is protected by copyright. All rights reserved....

  15. Sleep for cognitive enhancement

    Directory of Open Access Journals (Sweden)

    Susanne eDiekelmann

    2014-04-01

    Full Text Available Sleep is essential for effective cognitive functioning. Loosing even a few hours of sleep can have detrimental effects on a wide variety of cognitive processes such as attention, language, reasoning, decision making, learning and memory. While sleep is necessary to ensure normal healthy cognitive functioning, it can also enhance performance beyond the boundaries of the normal condition. This article discusses the enhancing potential of sleep, mainly focusing on the domain of learning and memory. Sleep is known to facilitate the consolidation of memories learned before sleep as well as the acquisition of new memories to be learned after sleep. According to a widely held model this beneficial effect of sleep relies on the neuronal reactivation of memories during sleep that is associated with sleep-specific brain oscillations (slow oscillations, spindles, ripples as well as a characteristic neurotransmitter milieu. Recent research indicates that memory processing during sleep can be boosted by (i cueing memory reactivation during sleep, (ii stimulating sleep-specific brain oscillations, and (iii targeting specific neurotransmitter systems pharmacologically. Olfactory and auditory cues can be used, for example, to increase reactivation of associated memories during post-learning sleep. Intensifying neocortical slow oscillations (the hallmark of slow wave sleep by electrical or auditory stimulation and modulating specific neurotransmitters such as noradrenaline and glutamate likewise facilitates memory processing during sleep. With this evidence in mind, this article concludes by discussing different methodological caveats and ethical issues that should be considered when thinking about using sleep for cognitive enhancement in everyday applications.

  16. Enhanced airglow at Titan

    Science.gov (United States)

    Royer, Emilie; Esposito, Larry; Wahlund, Jan-Erik

    2016-06-01

    The Cassini Ultraviolet Imaging Spectrograph (UVIS) instrument made thousand of observations of Titan since its arrival in the Saturnian system in 2004, but only few of them have been analyzed yet. Using the imaging capability of UVIS combined to a big data analytics approach, we have been able to uncover an unexpected pattern in this observations: on several occasions the Titan airglow exhibits an enhanced brightness by approximately a factor of 2, generally combined with a lower altitude of the airglow emission peak. These events typically last from 10 to 30 minutes and are followed and preceded by an airglow of regular and expected level of brightness and altitude. Observations made by the Cassini Plasma Spectrometer (CAPS) instrument onboard Cassini allowed us to correlate the enhanced airglow observed on T-32 with an electron burst. The timing of the burst and the level of energetic electrons (1 keV) observed by CAPS correspond to a brighter and lower than typical airglow displayed on the UVIS data. Furthermore, during T-32 Titan was inside the Saturn's magnetosheath and thus more subject to bombardment by energetic particles. However, our analysis demonstrates that the presence of Titan inside the magnetosheath is not a necessary condition for the production of an enhanced airglow, as we detected other similar events while Titan was within Saturn's magnetosphere. The study presented here aims to a better understanding of the interactions of Titan's upper atmosphere with its direct environment.

  17. Cognitive diversity and moral enhancement.

    Science.gov (United States)

    Gyngell, Chris; Easteal, Simon

    2015-01-01

    One debate in contemporary bioethics centers on whether the development of cognitive enhancement technologies (CETs) will hasten the need for moral enhancement. In this article we provide a new argument in favor of pursuing these enhancement technologies together. The widespread availability of CETs will likely increase population-level cognitive diversity. Different people will choose to enhance different aspects of their cognition, and some won't enhance themselves at all. Although this has the potential to be beneficial for society, it could also result in harms as people become more different from one another. Aspects of our moral psychology make it difficult for people to cooperate and coordinate actions with those who are very different from themselves. These moral failings could be targeted by moral enhancement technologies, which may improve cooperation among individuals. Moral enhancement technologies will therefore help society maximize the benefits, and reduce the costs, associated with widespread access to cognitive enhancements.

  18. Cell Growth Enhancement

    Science.gov (United States)

    1992-01-01

    Exogene Corporation uses advanced technologies to enhance production of bio-processed substances like proteins, antibiotics and amino acids. Among them are genetic modification and a genetic switch. They originated in research for Jet Propulsion Laboratory. Extensive experiments in cell growth through production of hemoglobin to improve oxygen supply to cells were performed. By improving efficiency of oxygen use by cells, major operational expenses can be reduced. Greater product yields result in decreased raw material costs and more efficient use of equipment. A broad range of applications is cited.

  19. Optical waveguide enhanced photovoltaics.

    Science.gov (United States)

    Rühle, Sven; Greenwald, Shlomit; Koren, Elad; Zaban, Arie

    2008-12-22

    Enhanced light to electric power conversion efficiency of photovoltaic cells with a low absorbance was achieved using waveguide integration. We present a proof of concept using a very thin dye-sensitized solar cell which absorbed only a small fraction of the light at normal incidence. The glass substrate in conjunction with the solar cells reflecting back contact formed a planar waveguide, which lead to more than four times higher conversion efficiency compared to conventional illumination at normal incidence. This illumination concept leads to a new type of multi-junction PV systems based on enforced spectral splitting along the waveguide.

  20. Enhancing LAN performance

    CERN Document Server

    Held, Gilbert

    2004-01-01

    Enhancing LAN Performance, Fourth Edition explains how to connect geographically separated LANs with appropriate bandwidth, the issues to consider when weighing the use of multiport or dualport devices, how to estimate traffic for new networks, the effects of configuration changes on the performance of Ethernet and Token Ring networks, the design of switch-based networks that prevent traffic bottlenecks, and other critical topics. It provides the tools to address these issues in relation to specific network requirements. This volume develops mathematical models of various LAN performance issue

  1. Universal threshold enhancement

    CERN Document Server

    Patkós, András; Szépfalusy, P; Szep, Zs.

    2003-01-01

    By assuming certain analytic properties of the propagator, it is shown that universal features of the spectral function including threshold enhancement arise if a pole describing a particle at high temperature approaches in the complex energy plane the threshold position of its two-body decay with the variation of T. The case is considered, when one can disregard any other decay processes. The quality of the proposed description is demonstrated by comparing it with the detailed large N solution of the linear sigma model around the pole-threshold coincidence.

  2. ICT Enhanced Buildings Potentials

    DEFF Research Database (Denmark)

    Christiansson, Per

    2007-01-01

    with focus on virtual building models support, new services and user environment definitions and development, virtual spaces and augmented reality, intelligent building components, application ontologies, and ICT systems integration to illustrate ICT enhanced buildings potentials and R&D needs.  ...... component systems that are accessed and integrated in the real world of building use in different contexts. The ICT systems may be physically or virtually embedded in the building. Already in 1982 AT&T established the 'intelligent buildings', IB, concept due to marketing reasons and the Informart building...

  3. Enhancing an R-matrix

    CERN Document Server

    MacKaay, M A

    1996-01-01

    In order to construct a representation of the tangle category one needs an enhanced R-matrix. In this paper we define a sufficient and necessary condition for enhancement that can be checked easily for any R-matrix. If the R-matrix can be enhanced, we also show how to construct the additional data that define the enhancement. As a direct consequence we find a sufficient condition for the construction of a knot invariant.

  4. Natural Enhancement of Color Image

    Directory of Open Access Journals (Sweden)

    Chen Shaohua

    2010-01-01

    Full Text Available A new algorithm of Natural Enhancement of Color Image (NECI is proposed. It is inspired by multiscale Retinex model. There are four steps to realize this enhancement. At first, the image appearance is rendered by content-dependent global mapping for light cast correction, and then a modified Retinex filter is applied to enhance the local contrast. Histogram rescaling is used afterwards for normalization purpose. At last, the texture details of image are enhanced by emphasizing the high-frequency components of image using multichannel decomposition of Cortex Transform. In the contrast enhancement step, luminance channel is firstly enhanced, and then a weighing map is calculated by collecting luminance enhancement information and applied to chrominance channel in color space CIELCh which enables a proportional enhancement of chrominance. It avoids the problem of unbalanced enhancement in classical RGB independent channel operation. In this work, it is believed that image enhancement should avoid dramatic modifications to image such as light condition changes, color temperature alteration, or additional artifacts introduced or amplified. Disregarding light conditions of the scene usually leads to unnaturally sharpened images or dramatic white balance changes. In the proposed method, the ambience of image (warm or cold color impression is maintained after enhancement, and no additional light sources are added to the scene, and no halo effect and blocking effect are amplified due to overenhancement. It realizes a Natural Enhancement of Color Image. Different types of natural scene images have been tested and an encouraging performance is obtained for the proposed method.

  5. Acoustically enhanced heat transport

    Energy Technology Data Exchange (ETDEWEB)

    Ang, Kar M.; Hung, Yew Mun; Tan, Ming K., E-mail: tan.ming.kwang@monash.edu [School of Engineering, Monash University Malaysia, 47500 Bandar Sunway, Selangor (Malaysia); Yeo, Leslie Y. [Micro/Nanophysics Research Laboratory, RMIT University, Melbourne, VIC 3001 (Australia); Friend, James R. [Department of Mechanical and Aerospace Engineering, University of California, San Diego, California 92093 (United States)

    2016-01-15

    We investigate the enhancement of heat transfer in the nucleate boiling regime by inducing high frequency acoustic waves (f ∼ 10{sup 6} Hz) on the heated surface. In the experiments, liquid droplets (deionized water) are dispensed directly onto a heated, vibrating substrate. At lower vibration amplitudes (ξ{sub s} ∼ 10{sup −9} m), the improved heat transfer is mainly due to the detachment of vapor bubbles from the heated surface and the induced thermal mixing. Upon increasing the vibration amplitude (ξ{sub s} ∼ 10{sup −8} m), the heat transfer becomes more substantial due to the rapid bursting of vapor bubbles happening at the liquid-air interface as a consequence of capillary waves travelling in the thin liquid film between the vapor bubble and the air. Further increases then lead to rapid atomization that continues to enhance the heat transfer. An acoustic wave displacement amplitude on the order of 10{sup −8} m with 10{sup 6} Hz order frequencies is observed to produce an improvement of up to 50% reduction in the surface temperature over the case without acoustic excitation.

  6. Acoustically enhanced heat transport

    Science.gov (United States)

    Ang, Kar M.; Yeo, Leslie Y.; Friend, James R.; Hung, Yew Mun; Tan, Ming K.

    2016-01-01

    We investigate the enhancement of heat transfer in the nucleate boiling regime by inducing high frequency acoustic waves (f ˜ 106 Hz) on the heated surface. In the experiments, liquid droplets (deionized water) are dispensed directly onto a heated, vibrating substrate. At lower vibration amplitudes (ξs ˜ 10-9 m), the improved heat transfer is mainly due to the detachment of vapor bubbles from the heated surface and the induced thermal mixing. Upon increasing the vibration amplitude (ξs ˜ 10-8 m), the heat transfer becomes more substantial due to the rapid bursting of vapor bubbles happening at the liquid-air interface as a consequence of capillary waves travelling in the thin liquid film between the vapor bubble and the air. Further increases then lead to rapid atomization that continues to enhance the heat transfer. An acoustic wave displacement amplitude on the order of 10-8 m with 106 Hz order frequencies is observed to produce an improvement of up to 50% reduction in the surface temperature over the case without acoustic excitation.

  7. Telemetry-Enhancing Scripts

    Science.gov (United States)

    Maimone, Mark W.

    2009-01-01

    Scripts Providing a Cool Kit of Telemetry Enhancing Tools (SPACKLE) is a set of software tools that fill gaps in capabilities of other software used in processing downlinked data in the Mars Exploration Rovers (MER) flight and test-bed operations. SPACKLE tools have helped to accelerate the automatic processing and interpretation of MER mission data, enabling non-experts to understand and/or use MER query and data product command simulation software tools more effectively. SPACKLE has greatly accelerated some operations and provides new capabilities. The tools of SPACKLE are written, variously, in Perl or the C or C++ language. They perform a variety of search and shortcut functions that include the following: Generating text-only, Event Report-annotated, and Web-enhanced views of command sequences; Labeling integer enumerations with their symbolic meanings in text messages and engineering channels; Systematic detecting of corruption within data products; Generating text-only displays of data-product catalogs including downlink status; Validating and labeling of commands related to data products; Performing of convenient searches of detailed engineering data spanning multiple Martian solar days; Generating tables of initial conditions pertaining to engineering, health, and accountability data; Simplified construction and simulation of command sequences; and Fast time format conversions and sorting.

  8. Direct vs. Indirect Moral Enhancement.

    Science.gov (United States)

    Schaefer, G Owen

    2015-09-01

    Moral enhancement is an ostensibly laudable project. Who wouldn't want people to become more moral? Still, the project's approach is crucial. We can distinguish between two approaches for moral enhancement: direct and indirect. Direct moral enhancements aim at bringing about particular ideas, motives or behaviors. Indirect moral enhancements, by contrast, aim at making people more reliably produce the morally correct ideas, motives or behaviors without committing to the content of those ideas, motives and/or actions. I will argue, on Millian grounds, that the value of disagreement puts serious pressure on proposals for relatively widespread direct moral enhancement. A more acceptable path would be to focus instead on indirect moral enhancements while staying neutral, for the most part, on a wide range of substantive moral claims. I will outline what such indirect moral enhancement might look like, and why we should expect it to lead to general moral improvement.

  9. Enhanced Geothermal Systems

    Energy Technology Data Exchange (ETDEWEB)

    Jeanloz, R. [The MITRE Corporation, McLean, VA (United States); Stone, H. [The MITRE Corporation, McLean, VA (United States); et al.

    2013-12-31

    DOE, through the Geothermal Technologies Office (GTO) within the Office of Energy Efficiency and Renewable Energy, requested this study, identifying a focus on: i) assessment of technologies and approaches for subsurface imaging and characterization so as to be able to validate EGS opportunities, and ii) assessment of approaches toward creating sites for EGS, including science and engineering to enhance permeability and increase the recovery factor. Two days of briefings provided in-depth discussion of a wide range of themes and challenges in EGS, and represented perspectives from industry, government laboratories and university researchers. JASON also contacted colleagues from universities, government labs and industry in further conversations to learn the state of the field and potential technologies relevant to EGS.

  10. Surface enhanced Raman scattering

    CERN Document Server

    Furtak, Thomas

    1982-01-01

    In the course of the development of surface science, advances have been identified with the introduction of new diagnostic probes for analytical characterization of the adsorbates and microscopic structure of surfaces and interfaces. Among the most recently de­ veloped techniques, and one around which a storm of controversy has developed, is what has now been earmarked as surface enhanced Raman scattering (SERS). Within this phenomenon, molecules adsorbed onto metal surfaces under certain conditions exhibit an anomalously large interaction cross section for the Raman effect. This makes it possible to observe the detailed vibrational signature of the adsorbate in the ambient phase with an energy resolution much higher than that which is presently available in electron energy loss spectroscopy and when the surface is in contact with a much larger amount of material than that which can be tolerated in infrared absorption experiments. The ability to perform vibrational spectroscopy under these conditions would l...

  11. Structure Size Enhanced Histogram

    Science.gov (United States)

    Wesarg, Stefan; Kirschner, Matthias

    Direct volume visualization requires the definition of transfer functions (TFs) for the assignment of opacity and color. Multi-dimensional TFs are based on at least two image properties, and are specified by means of 2D histograms. In this work we propose a new type of a 2D histogram which combines gray value with information about the size of the structures. This structure size enhanced (SSE) histogram is an intuitive approach for representing anatomical features. Clinicians — the users we are focusing on — are much more familiar with selecting features by their size than by their gradient magnitude value. As a proof of concept, we employ the SSE histogram for the definition of two-dimensional TFs for the visualization of 3D MRI and CT image data.

  12. Cavity enhanced atomic magnetometry

    CERN Document Server

    Crepaz, Herbert; Dumke, Rainer

    2015-01-01

    Atom sensing based on Faraday rotation is an indispensable method for precision measurements, universally suitable for both hot and cold atomic systems. Here we demonstrate an all-optical magnetometer where the optical cell for Faraday rotation spectroscopy is augmented with a low finesse cavity. Unlike in previous experiments, where specifically designed multipass cells had been employed, our scheme allows to use conventional, spherical vapour cells. Spherical shaped cells have the advantage that they can be effectively coated inside with a spin relaxation suppressing layer providing long spin coherence times without addition of a buffer gas. Cavity enhancement shows in an increase in optical polarization rotation and sensitivity compared to single-pass configurations.

  13. Enhancing the network synchronizability

    Institute of Scientific and Technical Information of China (English)

    ZHAO Ming; ZHOU Tao; CHEN Guan-rong; WANG Bing-hong

    2007-01-01

    The structural and dynamical properties, partic-ularly the small-world effect and scale-free feature, of com-plex networks have attracted tremendous interest and atten-tion in recent years. This article offers a brief review of one focal issue concerning the structural and dynamical behav-iors of complex network synchronization. In the presenta-tion, the notions of synchronization of dynamical systems on networks, stability of dynamical networks, and relationships between network structure and synchronizability, will be first introduced. Then, various technical methods for enhancing the network synchronizability will be discussed, which are roughly divided into two classes: Structural Modification and Coupling-Pattern Regulation, where the former includes three typical methods-dividing hub nodes, shortening average dis-tances, and deleting overload edges, while the latter mainly is a method of strengthening the hub-nodes' influence on the network.

  14. Teacher Enhancement Institute

    Science.gov (United States)

    Marshall-Bradley, Tina

    1994-01-01

    During the 1980's, a period of intense concern over educational quality in the United States, few indicators of U.S. student achievement garnered the interest of policy makers and pundits as successfully as the results of international testing in mathematics and science. This concern was so great that as a part of the Goals 2000 initiative, President George Bush indicated that 'By the year 2000, U.S. students should be first in the world in mathematics and science.' The Clinton Administration is placing a major emphasis, not only on rigorous academic standards and creating a new system for assessing students' progress, but also including professional development as a major focus. The argument being that teachers need more sustained, intensive training to prepare them to teach to higher standards. Executive order 12821 mandates that national laboratories 'assist in the mathematics and science education of our Nation's students, teachers, parents and the public by establishing programs at their agency to provide for training elementary and secondary school teachers to improve their knowledge of mathematics and science'. These and other issues led to the development of ideas for a project that addresses the need for excellence in mathematics, science and technology instruction. In response to these initiatives the NASA/LaRC Teacher Enhancement Institute was proposed. The TEI incorporated systemic reform perspectives, enhanced content knowledge for teachers, and teacher preparation. Emphasis was also placed on recruiting those educators who teach in impoverished urban school districts with at-risk student populations who have been traditionally under represented in science, mathematics, technology and engineering. Participants in the Teacher Enhancement Institute were 37 teachers from grades K-8, teaching in Region 2 in the state of Virginia, as well as 2 preservice teachers from Norfolk State University and one teacher from Dublin, Virginia, where a Science

  15. Surface enhanced thermo lithography

    KAUST Repository

    Coluccio, Maria Laura

    2017-01-13

    We used electroless deposition to fabricate clusters of silver nanoparticles (NPs) on a silicon substrate. These clusters are plasmonics devices that induce giant electromagnetic (EM) field increments. When those EM field are absorbed by the metal NPs clusters generate, in turn, severe temperature increases. Here, we used the laser radiation of a conventional Raman set-up to transfer geometrical patterns from a template of metal NPs clusters into a layer of thermo sensitive Polyphthalaldehyde (PPA) polymer. Temperature profile on the devices depends on specific arrangements of silver nanoparticles. In plane temperature variations may be controlled with (i) high nano-meter spatial precision and (ii) single Kelvin temperature resolution on varying the shape, size and spacing of metal nanostructures. This scheme can be used to generate strongly localized heat amplifications for applications in nanotechnology, surface enhanced thermo-lithography (SETL), biology and medicine (for space resolved cell ablation and treatment), nano-chemistry.

  16. Dimensional Enhancement via Supersymmetry

    CERN Document Server

    Faux, M G; Landweber, G D

    2009-01-01

    We explain how the representation theory associated with supersymmetry in diverse dimensions is encoded within the representation theory of supersymmetry in one time-like dimension. This is enabled by algebraic criteria, derived, exhibited, and utilized in this paper, which indicate which subset of one-dimensional supersymmetric models describe "shadows" of higher-dimensional models. This formalism delineates that minority of one-dimensional supersymmetric models which can "enhance" to accommodate extra dimensions. As a consistency test, we use our formalism to reproduce well-known conclusions about supersymmetric field theories using one-dimensional reasoning exclusively. And we introduce the notion of "phantoms" which usefully accommodate higher-dimensional gauge invariance in the context of shadow multiplets in supersymmetric quantum mechanics.

  17. Cavity enhanced atomic magnetometry.

    Science.gov (United States)

    Crepaz, Herbert; Ley, Li Yuan; Dumke, Rainer

    2015-10-20

    Atom sensing based on Faraday rotation is an indispensable method for precision measurements, universally suitable for both hot and cold atomic systems. Here we demonstrate an all-optical magnetometer where the optical cell for Faraday rotation spectroscopy is augmented with a low finesse cavity. Unlike in previous experiments, where specifically designed multipass cells had been employed, our scheme allows to use conventional, spherical vapour cells. Spherical shaped cells have the advantage that they can be effectively coated inside with a spin relaxation suppressing layer providing long spin coherence times without addition of a buffer gas. Cavity enhancement shows in an increase in optical polarization rotation and sensitivity compared to single-pass configurations.

  18. 人胰腺癌裸鼠皮下移植瘤模型MRI表现与病理对照研究%MRI Features and Pathology of Human Pancreatic Cancer Subcutaneously Implanted Tumor Model in Nude Mice

    Institute of Scientific and Technical Information of China (English)

    张梅花; 杨晓春; 沈钧康; 赵永华

    2015-01-01

    目的 探讨人胰腺癌裸鼠皮下移植瘤磁共振成像(MRI)检查技术及其影像学表现的病理机制.方法 建立人胰腺癌Patu8988细胞株裸鼠皮下移植瘤模型20只,细胞接种后2、4、6、7、8周随机抽取4只荷瘤鼠,进行大体观察、MRI检查和病理检查.大体观察荷瘤鼠和肿瘤的生长后进行MRI扫描,MRI平扫后,腹腔注射钆贝葡胺后4min行增强扫描,观察肿瘤影像学表现和周围组织情况;MRI检查后处死荷瘤鼠,解剖瘤灶,进行病理学研究,并与MR图像进行对照.结果 肿瘤接种成功率为100%.2周时瘤灶T1WI和T2WI信号较均匀,4~8周时瘤灶T1WI呈均匀等信号或稍高信号,T2WI呈不均匀混杂信号,增强扫描瘤灶不均匀强化,以瘤灶周缘强化明显,内可见斑片状无强化区,随着肿瘤的生长,其内无强化区逐渐扩大.结论 常规MR扫描技术能对胰腺癌皮下移植瘤的发生发展进行动态观察,移植瘤MRI表现可从病理学角度进行解释.%Objective To investigate the MRI features of human pancreatic cancer subcutaneously implanted tu-mor in nude mice and the pathomechanism of the MRI features. Methods Twenty nude mice were subcutaneously injected with human pancreatic cancer cells Patu8988 to establish the animal model. Every 4 mice were randomly sampled at 2, 4, 6, 7, and 8 weeks after inoculation of the cells to conduct gross observation, MR scanning, and pathological examination. After gross observation, the bearing tumors were scanned by MR and enhanced MR(4 min after Gd-BOPTA injection), and then the mice were sacrificed for pathological examination. MRI findings were compared with pathological findings. Results The successful rate of inoculation was 100%. The signal of two-week-old tumors showed iso-intensity on T1WI and T2WI, the signal of four- to eight-week-old tumors showed iso-intensity or slight hyper-intensity on T1WI, and mix-intensity on T2WI. The tumors were intensified at 4min postinjection of the

  19. Contrast-enhanced MR magnetization transfer technique. Improved tumor contrast, delineation, and visibility of malignant gliomas and brain metastases in radiochirurgical treatment planning; Kontrastmittelunterstuetzte MR ``Magnetization-transfer-Technik``. Verbesserter Tumorkontrast, Abgrenzbarkeit und Sichtbarkeit von intrakraniellen malignen Gliomen und Metastasen zur Tumorerkennung fuer die Radiochirurgie

    Energy Technology Data Exchange (ETDEWEB)

    Hawighorst, H.; Schreiber, W.; Knopp, M.V.; Brix, G.; Essig, M.; Kaick, G. van [Deutsches Krebsforschungszentrum (DKFZ), Heidelberg (Germany). Abt. Radiologische Diagnostik und Therapie; Debus, J.; Engenhart-Cabillic, R. [Radiologische Universitaetsklinik, Heidelberg (Germany). Abt. Strahlentherapie

    1997-12-01

    Patients and Methods: Thirty-two patients (mean age 47 years) with histologically proven or suspected high grade glioma (n=12) or metastatic brain lesions (n=20) were prospectively examined by MR imaging. After the administration of gadolinium dimeglumine (0.1 mmol/kg body weight) the lesions were imaged with T1-weighted MT-fast low angle shot (FLASH) pulse sequence and with a conventional T1-weighted SE sequence without MT saturation. Results: The mean CNR of enhancing lesions on T1-weighted MT-FLASH was 15{+-}5 compared to 11{+-}4 on SE images, representing a significant (p<.01) improvement. The mean tumor diameter of malignant gliomas was significantly (p<.01) larger measured on T1-weighted MT-FLASH images compared to those obtained from T1-weighted SE images and were comparable for metastatic lesions. Lesion conspicuity and delineation were improved in 50% of patients with high grade gliomas and in 35% of patients with brain metastases. Lesion conspicuity and delineation were improved in 50% of patients with high grade gliomas and in 35% of patients with brain metastases. Lesion conspicuity was markedly improved in the posterior fossa. Additional contrast enhancing lesions were detected in 10% of patients with metastases on MT-FLASH images. Conclusions: It is concluded that contrast-enhanced MT-FLASH images may improve lesion detection and delineation in the planning process of radiosurgery in patients with intracranial high grade gliomas or metastases or even alter the treatment approach. (orig./MG) [Deutsch] Patientengut und Methode: 32 Patienten (mittleres Alter 47 Jahre) mit hoehergradigen Gliomen (n=12) und Hirnmetastasen (n=20) unterschiedlicher Grunderkrankungen wurden prospektiv im Rahmen einer radiochirurgischen MR-Bestrahlungsplanung untersucht. Nach einem standardisierten Untersuchungsprotokoll wurden nach Kontrastmittelapplikation einer Standarddosis Gd-DTPA (0,1 mmol/kg Koerpergewicht) T1-gewichtete SE- und MT-FLASH-Sequenzen analysiert. Die Bilder

  20. Lignite Fuel Enhancement

    Energy Technology Data Exchange (ETDEWEB)

    Charles Bullinger; Nenad Sarunac

    2010-03-31

    Pulverized coal power plants which fire lignites and other low-rank high-moisture coals generally operate with reduced efficiencies and increased stack emissions due to the impacts of high fuel moisture on stack heat loss and pulverizer and fan power. A process that uses plant waste heat sources to evaporate a portion of the fuel moisture from the lignite feedstock in a moving bed fluidized bed dryer (FBD) was developed in the U.S. by a team led by Great River Energy (GRE). The demonstration was conducted with Department of Energy (DOE) funding under DOE Award Number DE-FC26-04NT41763. The objectives of GRE's Lignite Fuel Enhancement project were to demonstrate reduction in lignite moisture content by using heat rejected from the power plant, apply technology at full scale at Coal Creek Station (CCS), and commercialize it. The Coal Creek Project has involved several stages, beginning with lignite drying tests in a laboratory-scale FBD at the Energy Research Center (ERC) and development of theoretical models for predicting dryer performance. Using results from these early stage research efforts, GRE built a 2 ton/hour pilot-scale dryer, and a 75 ton/hour prototype drying system at Coal Creek Station. Operated over a range of drying conditions, the results from the pilot-scale and prototype-scale dryers confirmed the performance of the basic dryer design concept and provided the knowledge base needed to scale the process up to commercial size. Phase 2 of the GRE's Lignite Fuel Enhancement project included design, construction and integration of a full-scale commercial coal drying system (four FBDs per unit) with Coal Creek Units 1 and 2 heat sources and coal handling system. Two series of controlled tests were conducted at Coal Creek Unit 1 with wet and dried lignite to determine effect of dried lignite on unit performance and emissions. Wet lignite was fired during the first, wet baseline, test series conducted in September 2009. The second test series was

  1. Color image and video enhancement

    CERN Document Server

    Lecca, Michela; Smolka, Bogdan

    2015-01-01

    This text covers state-of-the-art color image and video enhancement techniques. The book examines the multivariate nature of color image/video data as it pertains to contrast enhancement, color correction (equalization, harmonization, normalization, balancing, constancy, etc.), noise removal and smoothing. This book also discusses color and contrast enhancement in vision sensors and applications of image and video enhancement.   ·         Focuses on enhancement of color images/video ·         Addresses algorithms for enhancing color images and video ·         Presents coverage on super resolution, restoration, in painting, and colorization.

  2. Backside configured surface plasmonic enhancement

    Energy Technology Data Exchange (ETDEWEB)

    Gu, Guiru; Lu, Xuejun, E-mail: xuejun-lu@uml.edu [Department of Electrical and Computer Engineering, University of Massachusetts Lowell, One University Avenue, Lowell, MA 01854 (United States); Vaillancourt, Jarrod [Applied NanoFemto Technologies, LLC, 181 Stedman St. 2, Lowell, MA 01851 (United States)

    2014-03-31

    In this work, we fabricated, measured and compared the quantum dots infrared photodetector enhancement by the top- and backside- configured plasmonic structures. The backside configured plasmonic structure can provide much higher device performance enhancement. Furthermore, the excitation of the surface plasmonic waves by the top- and backside- configured plasmonic structures was analyzed. Detailed simulation results of the electric field at different wavelength from top illumination and backside illumination were provided. The stronger electric field from the backside illumination attributed to the higher enhancement.

  3. Development of enhanced radioprotectors

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Jin Kyu; Chun, K. J.; Lee, Y. K.; Kim, Y. K.; Lee, B. H.; Song, H. S.; Lee, C. J.; Chung, K. M.; Shin, H. S.; Park, T. W

    2000-04-01

    Biological model systems such as TSH mutations, animals and their reproductive organs, and cultured cell lines and human peripheral lymphocytes have been set up for screening radioprotective or radiosensitizing activities of natural products. About 100 natural plants were in vivo and in vitro tested. Among them, Salvia miltiorrhiza, Areca catechu, Cornus officinalis, and portulaca oleracea showed 20 percent of radioprotective activities. On the other hand, Acanthopanax sessiliflous, Melia japonica, and Agastache rugosa revealed radiosensitizing activities. Experimental studies on the farnesyl transferase inhibitors showed the results that some of the inhibitors lead to higher levels of cell death after {gamma}-irradiation and increased radiosensitivity in H-ras-transformed NIH3T3 cells and MCF-10A human tumor cells. Molecular biochemical studies on the mechanism of radioprotection was carried out using cultured cells. The treatment of DTT increased cell survival after gamma-irradiation,decreased in the frequencies of micronucleus, and reduction in DNA fragmentation and apoptotic cells. Induction of apoptosis after irradiation was revealed by the changes in the relative cell death, increase in the relative amount of apoptotic cells, and the induction of DNA fragmentation. The result of mechanism studies will be applied to elucidate the radioprotection mechanism and to develop enhanced radioprotectors. Furthermore, our results indicate that use of antioxidants in combination can efficiently modulate the radiation-induced cell damage like apoptosis and can be applied to alleviate the cellular damage in tumor patients during radiotherapy. (author)

  4. Enhanced Design Alternative IV

    Energy Technology Data Exchange (ETDEWEB)

    N. E. Kramer

    1999-05-18

    This report evaluates Enhanced Design Alternative (EDA) IV as part of the second phase of the License Application Design Selection (LADS) effort. The EDA IV concept was compared to the VA reference design using criteria from the ''Design Input Request for LADS Phase II EDA Evaluations'' (CRWMS M&O 1999b) and (CRWMS M&O 1999f). Briefly, the EDA IV concept arranges the waste packages close together in an emplacement configuration known as ''line load''. Continuous pre-closure ventilation keeps the waste packages from exceeding the 350 C cladding and 200 C (4.3.13) drift wall temperature limits. This EDA concept keeps relatively high, uniform emplacement drift temperatures (post-closure) to drive water away from the repository and thus dry out the pillars between emplacement drifts. The waste package is shielded to permit human access to emplacement drifts and includes an integral filler inside the package to reduce the amount of water that can contact the waste form. Closure of the repository is desired 50 years after first waste is emplaced. Both backfill and a drip shields will be emplaced at closure to improve post-closure performance.

  5. Development of enhanced radioprotectors

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Jin Kyu; Park, K.B.; Lee, Y.I. [and others

    1999-04-01

    Biological model systems such as TSH mutations, animals and their reproductive organs, and cultured cell lines has been set up for screening radioprotective or radiosensitizing activities of natural products. About 100 natural plants were in vivo and in vitro tested. Among them, Salvia miltiorrhiza, Areca catechu, Cornus officinalis, and Portulaca oleracea showed 20% of radioprotective activities. On the other hand, Acanthopanax sessiliflous, Melia japonica, and Agastache rugosa revealed radiosensitizing activities. Experimental studies on the farnesyltransferase inhibitors showed the results that some of the inhibits lead to higher levels of cell death after {gamma} -irradiation and increased radiosensitivity in H-ras-transformed NIH3T3 cells and MCF-10A human tumor cells. Molecular biochemical studies on the mechanism of radioprotection was carried out using cultured cells. The treatment of DTT increased cell survival after gamma-irradiation, decreased in the frequencies of micronucleus, and reduction in DNA fragmentation and apoptotic cells. Induction of apoptosis after irradiation was revealed by the changes in the relative cell death, increase in the relative amount of apoptotic cells, and the induction of DNA fragmentation. Samples shown excellent radioprotective or radiosensitizing activities will be subjected to purification to develop radioprotectants and radiosensitizers applicable to human beings. The result of mechanism studies will be applied to elucidate the radioprotection mechanism and the develop enhanced radioprotectors. (author). 145 refs., 21 tabs., 29 figs.

  6. Enhanced Micellar Catalysis LDRD.

    Energy Technology Data Exchange (ETDEWEB)

    Betty, Rita G.; Tucker, Mark D; Taggart, Gretchen; Kinnan, Mark K.; Glen, Crystal Chanea; Rivera, Danielle; Sanchez, Andres; Alam, Todd Michael

    2012-12-01

    The primary goals of the Enhanced Micellar Catalysis project were to gain an understanding of the micellar environment of DF-200, or similar liquid CBW surfactant-based decontaminants, as well as characterize the aerosolized DF-200 droplet distribution and droplet chemistry under baseline ITW rotary atomization conditions. Micellar characterization of limited surfactant solutions was performed externally through the collection and measurement of Small Angle X-Ray Scattering (SAXS) images and Cryo-Transmission Electron Microscopy (cryo-TEM) images. Micellar characterization was performed externally at the University of Minnesotas Characterization Facility Center, and at the Argonne National Laboratory Advanced Photon Source facility. A micellar diffusion study was conducted internally at Sandia to measure diffusion constants of surfactants over a concentration range, to estimate the effective micelle diameter, to determine the impact of individual components to the micellar environment in solution, and the impact of combined components to surfactant phase behavior. Aerosolized DF-200 sprays were characterized for particle size and distribution and limited chemical composition. Evaporation rates of aerosolized DF-200 sprays were estimated under a set of baseline ITW nozzle test system parameters.

  7. Enhancing a Universe Below

    Energy Technology Data Exchange (ETDEWEB)

    Berge, Gunnar

    1998-12-31

    By understanding the past and by means of modern technology the petroleum resources can be exploited in an environmentally friendly and cost-effective way. Since the future of the oil and gas industry depends on the size and availability of the remaining resources and on the demand for the products, this presentation aims to overview these resources, globally and on the Norwegian Shelf. It also considers the uncertainty in the future demand for oil and gas. A key challenge for the industry is to enhance the value of these resources without compromising environmental values. The industry will also have to face issues such as deregulation of the energy markets, hydrocarbon taxation, etc. These challenges also provide possibilities for a proactive industry; how can we make the industry more competitive? New oil and gas fields are now being developed in deeper water, in harsh climate conditions and in vulnerable environments. These challenges call for technological development and strong focus on safety and environmental issues. Long-term commercial commitment and cooperation of the industry is essential for new technologies and for training. 2 figs.

  8. Multispectral histogram normalization contrast enhancement

    Science.gov (United States)

    Soha, J. M.; Schwartz, A. A.

    1979-01-01

    A multispectral histogram normalization or decorrelation enhancement which achieves effective color composites by removing interband correlation is described. The enhancement procedure employs either linear or nonlinear transformations to equalize principal component variances. An additional rotation to any set of orthogonal coordinates is thus possible, while full histogram utilization is maintained by avoiding the reintroduction of correlation. For the three-dimensional case, the enhancement procedure may be implemented with a lookup table. An application of the enhancement to Landsat multispectral scanning imagery is presented.

  9. What are super-enhancers?

    Science.gov (United States)

    Pott, Sebastian; Lieb, Jason D

    2015-01-01

    The term 'super-enhancer' has been used to describe groups of putative enhancers in close genomic proximity with unusually high levels of Mediator binding, as measured by chromatin immunoprecipitation and sequencing (ChIP-seq). Here we review the identification and composition of super-enhancers, describe links between super-enhancers, gene regulation and disease, and discuss the functional significance of enhancer clustering. We also provide our perspective regarding the proposition that super-enhancers are a regulatory entity conceptually distinct from what was known before the introduction of the term. Our opinion is that there is not yet strong evidence that super-enhancers are a novel paradigm in gene regulation and that use of the term in this context is not currently justified. However, the term likely identifies strong enhancers that exhibit behaviors consistent with previous models and concepts of transcriptional regulation. In this respect, the super-enhancer definition is useful in identifying regulatory elements likely to control genes important for cell type specification.

  10. PENETRATION ENHANCERS: A NOVEL STRATEGY FOR ENHANCING TRANSDERMAL DRUG DELIVERY

    Directory of Open Access Journals (Sweden)

    Singla Vikas

    2011-12-01

    Full Text Available Skin penetration enhancers have been used to improve bioavailability and increase the range of drugs to be administered by topical and transdermal route. Enhancement in skin penetration via modification of the stratum corneum by hydration, or via use of chemical enhancers acting on the structure of the stratum corneum lipids and keratin, partitioning and solubility effects. The mechanism of action of penetration enhancers are used as an aid in potential clinical applications. Synthetic chemicals generally used for this purposes are rapidly losing their value in transdermal patches due to reports of their absorption into the systemic circulation and subsequent possible toxic effect upon long term application. Terpenes are included in the list of Generally Recognized as Safe (GRAS substances and have low irritancy potential. In this review, we have discussed the chemical penetration as well as natural penetration enhancement technology for transdermal drug delivery as well as the probable mechanisms of action.

  11. Enhancers, enhancers - from their discovery to today's universe of transcription enhancers.

    Science.gov (United States)

    Schaffner, Walter

    2015-04-01

    Transcriptional enhancers are short (200-1500 base pairs) DNA segments that are able to dramatically boost transcription from the promoter of a target gene. Originally discovered in simian virus 40 (SV40), a small DNA virus, transcription enhancers were soon also found in immunoglobulin genes and other cellular genes as key determinants of cell-type-specific gene expression. Enhancers can exert their effect over long distances of thousands, even hundreds of thousands of base pairs, either from upstream, downstream, or from within a transcription unit. The number of enhancers in eukaryotic genomes correlates with the complexity of the organism; a typical mammalian gene is likely controlled by several enhancers to fine-tune its expression at different developmental stages, in different cell types and in response to different signaling cues. Here, I provide a personal account of how enhancers were discovered more than 30 years ago, and also address the amazing development of the field since then.

  12. Plasmon Enhanced Photoemission

    Energy Technology Data Exchange (ETDEWEB)

    Polyakov, Aleksandr [Univ. of California, Berkeley, CA (United States)

    2012-05-08

    this work, the structure consisted of rectangular nano-grooves (NGs) arranged in a subwavelength grating on a metal surface is presented that provides a dramatic increase in the metal’s absorption, field localization, and field enhancement. When light is polarized perpendicular to the orientation of the grooves a standing SPP wave is excited along the vertical walls in the NGs, that act as Fabry-Perot resonators. By adjusting the geometry of the NGs and the period of the subwavelength grating the resonance can be fine tuned to a desired position, for example, the laser fundamental wavelength, anywhere from the UV to the near infrared (NIR). Two types of gratings are presented: (a) a gold grating with period of 600 nm, and (b) an aluminum-gold grating with a period of 100 nm; both with resonance at 720 nm. In each case, strong on-resonance absorption was observed, with over 98% for grating (b). Unlike the grating-coupled SPP waves, where the angle is well defined by the momentum matching condition, the resonant NGs allow coupling to the standing modes at a range of angles of incidence, referred to as the angular bandwidth. A new model for the on-resonance absorption based on the ensamble action of the NGs is presented that serves as the basis for a design of an NG grating with an ultrawide spectral as well as angular bandwidth. For sample (b), the angular bandwidth is 80 degrees, corresponding to an opening angle of 160 degrees. The photoemission enhancement for such a grating was measured to be seven orders of magnitude for a four-photon photoemission. This is an incredible result demonstrating the power of the plasmonic grating presented, which is an efficient light trapper and field enhancer for a non-linear processes. These results demonstrate that the metal photocathode prepared with a NG grating on the metal surface will provide sufficient pulse charge driven by a 1 μJ 15fs pulsed laser at 800 nm for the optimum FEL operation.

  13. Motif signatures of transcribed enhancers

    KAUST Repository

    Kleftogiannis, Dimitrios

    2017-09-14

    In mammalian cells, transcribed enhancers (TrEn) play important roles in the initiation of gene expression and maintenance of gene expression levels in spatiotemporal manner. One of the most challenging questions in biology today is how the genomic characteristics of enhancers relate to enhancer activities. This is particularly critical, as several recent studies have linked enhancer sequence motifs to specific functional roles. To date, only a limited number of enhancer sequence characteristics have been investigated, leaving space for exploring the enhancers genomic code in a more systematic way. To address this problem, we developed a novel computational method, TELS, aimed at identifying predictive cell type/tissue specific motif signatures. We used TELS to compile a comprehensive catalog of motif signatures for all known TrEn identified by the FANTOM5 consortium across 112 human primary cells and tissues. Our results confirm that distinct cell type/tissue specific motif signatures characterize TrEn. These signatures allow discriminating successfully a) TrEn from random controls, proxy of non-enhancer activity, and b) cell type/tissue specific TrEn from enhancers expressed and transcribed in different cell types/tissues. TELS codes and datasets are publicly available at http://www.cbrc.kaust.edu.sa/TELS.

  14. Metaheuristic applications to speech enhancement

    CERN Document Server

    Kunche, Prajna

    2016-01-01

    This book serves as a basic reference for those interested in the application of metaheuristics to speech enhancement. The major goal of the book is to explain the basic concepts of optimization methods and their use in heuristic optimization in speech enhancement to scientists, practicing engineers, and academic researchers in speech processing. The authors discuss why it has been a challenging problem for researchers to develop new enhancement algorithms that aid in the quality and intelligibility of degraded speech. They present powerful optimization methods to speech enhancement that can help to solve the noise reduction problems. Readers will be able to understand the fundamentals of speech processing as well as the optimization techniques, how the speech enhancement algorithms are implemented by utilizing optimization methods, and will be given the tools to develop new algorithms. The authors also provide a comprehensive literature survey regarding the topic.

  15. Resolution Enhancement of Multilook Imagery

    Energy Technology Data Exchange (ETDEWEB)

    Galbraith, Amy E. [Univ. of Arizona, Tucson, AZ (United States)

    2004-07-01

    This dissertation studies the feasibility of enhancing the spatial resolution of multi-look remotely-sensed imagery using an iterative resolution enhancement algorithm known as Projection Onto Convex Sets (POCS). A multi-angle satellite image modeling tool is implemented, and simulated multi-look imagery is formed to test the resolution enhancement algorithm. Experiments are done to determine the optimal con guration and number of multi-angle low-resolution images needed for a quantitative improvement in the spatial resolution of the high-resolution estimate. The important topic of aliasing is examined in the context of the POCS resolution enhancement algorithm performance. In addition, the extension of the method to multispectral sensor images is discussed and an example is shown using multispectral confocal fluorescence imaging microscope data. Finally, the remote sensing issues of atmospheric path radiance and directional reflectance variations are explored to determine their effect on the resolution enhancement performance.

  16. Enhanced incoherent scatter plasma lines

    Directory of Open Access Journals (Sweden)

    H. Nilsson

    Full Text Available Detailed model calculations of auroral secondary and photoelectron distributions for varying conditions have been used to calculate the theoretical enhancement of incoherent scatter plasma lines. These calculations are compared with EISCAT UHF radar measurements of enhanced plasma lines from both the E and F regions, and published EISCAT VHF radar measurements. The agreement between the calculated and observed plasma line enhancements is good. The enhancement from the superthermal distribution can explain even the very strong enhancements observed in the auroral E region during aurora, as previously shown by Kirkwood et al. The model calculations are used to predict the range of conditions when enhanced plasma lines will be seen with the existing high-latitude incoherent scatter radars, including the new EISCAT Svalbard radar. It is found that the detailed structure, i.e. the gradients in the suprathermal distribution, are most important for the plasma line enhancement. The level of superthermal flux affects the enhancement only in the region of low phase energy where the number of thermal electrons is comparable to the number of suprathermal electrons and in the region of high phase energy where the suprathermal fluxes fall to such low levels that their effect becomes small compared to the collision term. To facilitate the use of the predictions for the different radars, the expected signal- to-noise ratios (SNRs for typical plasma line enhancements have been calculated. It is found that the high-frequency radars (Søndre Strømfjord, EISCAT UHF should observe the highest SNR, but only for rather high plasma frequencies. The VHF radars (EISCAT VHF and Svalbard will detect enhanced plasma lines over a wider range of frequencies, but with lower SNR.

  17. Environmental engineering education enhancement

    Science.gov (United States)

    Caporali, E.

    2012-04-01

    Since higher education plays a central role in the development of both human beings and modern societies, enhancing social, cultural and economic development, active citizenship, ethical values and expertises for a sustainable growth, environment respectful, the European Commission promotes a wide range of programmes. Among the EC programmes, the TEMPUS - Trans European Mobility Programme for University Studies, with the support of the DG EAC of the European Commission, has contributed to many aspects of general interest for higher education. Curricula harmonization, LifeLong Learning Programme development, ICT use, quality assessment, accreditation, innovation learning methods, growth of networks of institutions trusting each other, are the focused aspects. Such a solid cooperation framework is surely among the main outcomes of the TEMPUS Projects leaded by the University of Firenze UNIFI (Italy), DEREC - Development of Environment and Resources Engineering Curriculum (2005-2008), and its spin-off DEREL - Development of Environment and Resources Engineering Learning (2010-2013), and VICES - Videoconferencing Educational Services (2009-2012). DEREC and DEREL TEMPUS projects, through the co-operation of Universities in Italy, Austria, Germany, Greece, Macedonia, Albania and Serbia, are aimed at the development of first and second level curricula in "Environment and Resources Engineering" at the Ss. Cyril and Methodius University - UKIM Skopje (MK). In the DEREC Project the conditions for offering a joint degree title in the field of Environmental Engineering between UNIFI and UKIM Skopje were fulfilled and a shared educational programme leading to the mutual recognition of degree titles was defined. The DEREL project, as logical continuation of DEREC, is aimed to introduce a new, up-to-date, postgraduate second level curriculum in Environment and Resources Engineering at UKIM Skopje, University of Novi Sad (RS) and Polytechnic University of Tirana (AL). following

  18. Fuzzy-Contextual Contrast Enhancement.

    Science.gov (United States)

    Parihar, Anil; Verma, Om; Khanna, Chintan

    2017-02-08

    This paper presents contrast enhancement algorithms based on fuzzy contextual information of the images. We introduce fuzzy similarity index and fuzzy contrast factor to capture the neighborhood characteristics of a pixel. A new histogram, using fuzzy contrast factor of each pixel is developed, and termed as the fuzzy dissimilarity histogram (FDH). A cumulative distribution function (CDF) is formed with normalized values of FDH and used as a transfer function to obtain the contrast enhanced image. The algorithm gives good contrast enhancement and preserves the natural characteristic of the image. In order to develop a contextual intensity transfer function, we introduce a fuzzy membership function based on fuzzy similarity index and coefficient of variation of the image. The contextual intensity transfer function is designed using the fuzzy membership function to achieve final contrast enhanced image. The overall algorithm is referred as the fuzzy contextual contrast-enhancement (FCCE) algorithm. The proposed algorithms are compared with conventional and state-of-art contrast enhancement algorithms. The quantitative and visual assessment of the results is performed. The results of quantitative measures are statistically analyzed using t-test. The exhaustive experimentation and analysis show the proposed algorithm efficiently enhances contrast and yields in natural visual quality images.

  19. Resolution enhancement in tilted coordinates

    Science.gov (United States)

    Hariri Naghadeh, Diako; Keith Morley, Christopher

    2016-11-01

    Deconvolution is applied to remove source wavelet effects from seismograms. The results are resolution enhancement that enables detection of thin layers. Following enhancement of resolution, low frequency and high angle reflectors, particularly at great depth, appear as low amplitude and semi-invisible reflectors that are difficult to track and pick. A new approach to enhance resolution is introduced that estimates a derivative using continuous wavelet transform in tilted coordinates. The results are compared with sparse spike deconvolution, curvelet deconvolution and inverse quality filtering in wavelet domain. The positive consequence of the new method is to increase sampling of high dip features by changing the coordinate system from Cartesian to tilted. To compare those methods a complex data set was chosen that includes high angle faults and chaotic mass transport complex. Image enhancement using curvelet deconvolution shows a chaotic system as a non-chaotic one. The results show that sparse spike deconvolution and inverse quality filtering in wavelet domain are able to enhance resolution more than curvelet deconvolution especially at great depth but it is impossible to follow steep dip reflectors after resolution enhancement using these methods, especially when their apparent dips are more than 45°. By estimating derivatives in a continuous wavelet transform from tilted data sets similar resolution enhancement as the other deconvolution methods is achieved but additionally steep dipping reflectors are imaged much better than others. Subtracted results of the enhanced resolution data set using new method and the other introduced methods show that steeply dipping reflectors are highlighted as a particular ability of the new method. The results show that high frequency recovery in Cartesian co-ordinate is accompanied by inability to image steeply dipping reflectors especially at great depths. Conversely recovery of high frequency data and imaging of the data

  20. Resolution enhancement techniques in microscopy

    Science.gov (United States)

    Cremer, Christoph; Masters, Barry R.

    2013-05-01

    We survey the history of resolution enhancement techniques in microscopy and their impact on current research in biomedicine. Often these techniques are labeled superresolution, or enhanced resolution microscopy, or light-optical nanoscopy. First, we introduce the development of diffraction theory in its relation to enhanced resolution; then we explore the foundations of resolution as expounded by the astronomers and the physicists and describe the conditions for which they apply. Then we elucidate Ernst Abbe's theory of optical formation in the microscope, and its experimental verification and dissemination to the world wide microscope communities. Second, we describe and compare the early techniques that can enhance the resolution of the microscope. Third, we present the historical development of various techniques that substantially enhance the optical resolution of the light microscope. These enhanced resolution techniques in their modern form constitute an active area of research with seminal applications in biology and medicine. Our historical survey of the field of resolution enhancement uncovers many examples of reinvention, rediscovery, and independent invention and development of similar proposals, concepts, techniques, and instruments. Attribution of credit is therefore confounded by the fact that for understandable reasons authors stress the achievements from their own research groups and sometimes obfuscate their contributions and the prior art of others. In some cases, attribution of credit is also made more complex by the fact that long term developments are difficult to allocate to a specific individual because of the many mutual connections often existing between sometimes fiercely competing, sometimes strongly collaborating groups. Since applications in biology and medicine have been a major driving force in the development of resolution enhancing approaches, we focus on the contribution of enhanced resolution to these fields.

  1. Dural enhancement in pituitary macroadenomas

    Energy Technology Data Exchange (ETDEWEB)

    Cattin, F. [Dept. of Neuroradiology, University Hospital of Besancon (France); Dept. of Neuroradiology, Jean Minjoz Hospital, Besancon (France); Bonneville, F.; Andrea, I.; Barrali, E.; Bonneville, J.F. [Dept. of Neuroradiology, University Hospital of Besancon (France)

    2000-07-01

    We describe the normal dural enhancement patterns of the sellar region and determine whether the duramater is affected by pituitary macroadenomas. Dural enhancement appeared to be usually abnormal in 20 patients with pituitary macroadenoma compared with 20 control patients, mainly at the planum sphenoidale and carotid sulcus. However dural changes are subtle and their recognition requires knowledge of the normal enhancement patterns. Dural changes, reported in a variety of inflammatory and infectious dural diseases and after surgery, are not specific and may be also seen in pituitary macroadenomas. (orig.)

  2. Speech enhancement theory and practice

    CERN Document Server

    Loizou, Philipos C

    2013-01-01

    With the proliferation of mobile devices and hearing devices, including hearing aids and cochlear implants, there is a growing and pressing need to design algorithms that can improve speech intelligibility without sacrificing quality. Responding to this need, Speech Enhancement: Theory and Practice, Second Edition introduces readers to the basic problems of speech enhancement and the various algorithms proposed to solve these problems. Updated and expanded, this second edition of the bestselling textbook broadens its scope to include evaluation measures and enhancement algorithms aimed at impr

  3. Enhanced Master Station History Report

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The Enhanced Master Station History Report (EMSHR) is a compiled list of basic, historical information for every station in the station history database, beginning...

  4. [1990 annual waterfowl enhancement report

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — A memorandum from the Upper Souris NWR Refuge Manager to the regional office prefaces the attachment of the station's Annual Waterfowl Enhancement Report forms. The...

  5. Field enhancement induced laser ablation

    DEFF Research Database (Denmark)

    Fiutowski, Jacek; Maibohm, Christian; Kjelstrup-Hansen, Jakob

    Sub-diffraction spatially resolved, quantitative mapping of strongly localized field intensity enhancement on gold nanostructures via laser ablation of polymer thin films is reported. Illumination using a femtosecond laser scanning microscope excites surface plasmons in the nanostructures...

  6. Ultrasonic enhancement of battery diffusion.

    Science.gov (United States)

    Hilton, R; Dornbusch, D; Branson, K; Tekeei, A; Suppes, G J

    2014-03-01

    It has been demonstrated that sonic energy can be harnessed to enhance convection in Galvanic cells during cyclic voltammetry; however, the practical value of this approach is limited due to the lack of open volumes for convection patterns to develop in most batteries. This study evaluates the ability of ultrasonic waves to enhance diffusion in membrane separators commonly used in sandwich-architecture batteries. Studies include the measuring of open-circuit performance curves to interpret performances in terms of reductions in concentration overpotentials. The use of a 40 kHz sonicator bath can consistently increase the voltage of the battery and reduce overpotential losses up to 30%. This work demonstrates and quantifies battery enhancement due to enhanced diffusion made possible with ultrasonic energy.

  7. Enhanced Brine Dewatering System Project

    Data.gov (United States)

    National Aeronautics and Space Administration — The purpose of the Enhanced Brine Dewatering System (EBDS) is to provide a scalable means of completely recovering usable water from byproducts created by reverse...

  8. Cognitive enhancement: a brief overview

    African Journals Online (AJOL)

    Keywords: ADHD, attention deficit/hyperactivity disorder, cognitive enhancement, high workload, narcolepsy, stress ... as effective and easier alternatives to more time-consuming ... reduce fatigue, thereby increasing training and/or learning.

  9. Moderate eugenics and human enhancement.

    Science.gov (United States)

    Selgelid, Michael J

    2014-02-01

    Though the reputation of eugenics has been tarnished by history, eugenics per se is not necessarily a bad thing. Many advocate a liberal new eugenics--where individuals are free to choose whether or not to employ genetic technologies for reproductive purposes. Though genetic interventions aimed at the prevention of severe genetic disorders may be morally and socially acceptable, reproductive liberty in the context of enhancement may conflict with equality. Enhancement could also have adverse effects on utility. The enhancement debate requires a shift in focus. What the equality and/or utility costs of enhancement will be is an empirical question. Rather than philosophical speculation, more social science research is needed to address it. Philosophers, meanwhile, should address head-on the question of how to strike a balance between liberty, equality, and utility in cases of conflict (in the context of genetics).

  10. Geothermal Permeability Enhancement - Final Report

    Energy Technology Data Exchange (ETDEWEB)

    Joe Beall; Mark Walters

    2009-06-30

    The overall objective is to apply known permeability enhancement techniques to reduce the number of wells needed and demonstrate the applicability of the techniques to other undeveloped or under-developed fields. The Enhanced Geothermal System (EGS) concept presented in this project enhances energy extraction from reduced permeability zones in the super-heated, vapor-dominated Aidlin Field of the The Geysers geothermal reservoir. Numerous geothermal reservoirs worldwide, over a wide temperature range, contain zones of low permeability which limit the development potential and the efficient recovery of heat from these reservoirs. Low permeability results from poorly connected fractures or the lack of fractures. The Enhanced Geothermal System concept presented here expands these technologies by applying and evaluating them in a systematic, integrated program.

  11. Enhanced Brine Dewatering System Project

    Data.gov (United States)

    National Aeronautics and Space Administration — The purpose of the Enhanced Brine Dewatering System (EBDS) is to provide an easily scalable means of completely recovering usable water from byproducts created by...

  12. Non-pharmacological cognitive enhancement

    NARCIS (Netherlands)

    Dresler, M.; Sandberg, A.; Ohla, K.; Bublitz, C.; Trenado, C.; Mroczko-Wasowicz, A.; Kuhn, S.; Repantis, D.

    2013-01-01

    The term "cognitive enhancement" usually characterizes interventions in humans that aim to improve mental functioning beyond what is necessary to sustain or restore good health. While the current bioethical debate mainly concentrates on pharmaceuticals, according to the given characterization,

  13. Bose enhancement and the ridge

    Energy Technology Data Exchange (ETDEWEB)

    Altinoluk, Tolga [Departamento de Física de Partículas and IGFAE, Universidade de Santiago de Compostela, 15706 Santiago de Compostela, Galicia (Spain); Armesto, Néstor, E-mail: nestor.armesto@usc.es [Departamento de Física de Partículas and IGFAE, Universidade de Santiago de Compostela, 15706 Santiago de Compostela, Galicia (Spain); Beuf, Guillaume [Department of Physics, Ben-Gurion University of the Negev, Beer Sheva 84105 (Israel); Kovner, Alex [Physics Department, University of Connecticut, 2152 Hillside Road, Storrs, CT 06269-3046 (United States); Lublinsky, Michael [Department of Physics, Ben-Gurion University of the Negev, Beer Sheva 84105 (Israel)

    2015-12-17

    We point out that Bose enhancement in a hadronic wave function generically leads to correlations between produced particles. We show explicitly, by calculating the projectile density matrix in the Color Glass Condensate approach to high-energy hadronic collisions, that the Bose enhancement of gluons in the projectile leads to azimuthal collimation of long range rapidity correlations of the produced particles, the so-called ridge correlations.

  14. Multispectral Enhancement towards Digital Staining

    Directory of Open Access Journals (Sweden)

    Pinky A. Bautista

    2012-01-01

    Full Text Available Background: Digital staining can be considered as a special form of image enhancement wherein the concern is not only to increase the contrast between the background objects and objects of interest, but to also impart the colors that mark the objects’ unique reactions to a specific stain. In this paper, we extended the previously proposed multispectral enhancement methods such that the colors of the background pixels can also be changed.

  15. Bose enhancement and the ridge

    CERN Document Server

    Altinoluk, Tolga; Beuf, Guillaume; Kovner, Alex; Lublinsky, Michael

    2015-01-01

    We point out that Bose enhancement in a hadronic wave function generically leads to correlations between produced particles. We show explicitly, by calculating the projectile density matrix in the Color Glass Condensate approach to high-energy hadronic collisions, that the Bose enhancement of gluons in the projectile leads to azimuthal collimation of long range rapidity correlations of the produced particles, the so-called ridge correlations.

  16. Bose enhancement and the ridge

    Directory of Open Access Journals (Sweden)

    Tolga Altinoluk

    2015-12-01

    Full Text Available We point out that Bose enhancement in a hadronic wave function generically leads to correlations between produced particles. We show explicitly, by calculating the projectile density matrix in the Color Glass Condensate approach to high-energy hadronic collisions, that the Bose enhancement of gluons in the projectile leads to azimuthal collimation of long range rapidity correlations of the produced particles, the so-called ridge correlations.

  17. Contrast-enhanced endoscopic ultrasonography

    DEFF Research Database (Denmark)

    Reddy, Nischita K; Ioncica, Ana Maria; Saftoiu, Adrian;

    2011-01-01

    agents and their use in various endoscopic procedures in the gastrointestinal tract. Various applications of contrast-enhanced endoscopic ultrasonography include differentiating benign from malignant mediastinal lymphadenopathy, assessment of depth of invasion of esophageal, gastric and gall bladder...... sonography to depict tumor neovascularization can be increased by contrast agents. Contrast-enhanced harmonic imaging is a useful aid in identifying the tumor vasculature and studying pancreatic microperfusion. In the future, these techniques could potentially be used to quantify tumor perfusion, to assess...

  18. Chemically enhanced in situ recovery

    Energy Technology Data Exchange (ETDEWEB)

    Sale, T. [CH2M Hill, Denver, CO (United States); Pitts, M.; Wyatt, K. [Surtek, Inc., Golden, CO (United States)] [and others

    1996-08-01

    Chemically enhanced recovery is a promising alternative to current technologies for management of subsurface releases of organic liquids. Through the inclusion of surfactants, solvents, polymers, and/or alkaline agents to a waterflood, the transport of targeted organic compounds can be increased and rates of recovery enhanced. By far, the vast majority of work done in the field of chemically enhanced recovery has been at a laboratory scale. The following text focuses on chemically enhanced recovery from a field application perspective with emphasis given to chlorinated solvents in a low permeability setting. While chlorinated solvents are emphasized, issues discussed are also relevant to organic liquids less dense than water such as petroleum products. Topics reviewed include: (1) Description of technology; (2) General technology considerations; (3) Low permeability media considerations; (4) Cost and reliability considerations; (5) Commercial availability; and (6) Case histories. Through this paper an appreciation is developed of both the potential and limitations of chemically enhanced recovery. Excluded from the scope of this paper is the in situ destruction of organic compounds through processes such as chemical or biological oxidation, chemically enhanced recovery of inorganic compounds, and ex situ soil treatment processes. 11 refs., 2 figs., 1 tab.

  19. Speciation of gadolinium in surface water samples and plants by hydrophilic interaction chromatography hyphenated with inductively coupled plasma mass spectrometry.

    Science.gov (United States)

    Lindner, Uwe; Lingott, Jana; Richter, Silke; Jakubowski, Norbert; Panne, Ulrich

    2013-02-01

    Hydrophilic interaction chromatography (HILIC) coupled with inductively coupled plasma mass spectrometry (ICP-MS) was optimized for speciation analysis of gadolinium-based contrast agents in environmental samples, in particular surface river waters and plants. Surface water samples from the Teltow channel, near Berlin, were investigated over a distance of 5 km downstream from the influx of a wastewater treatment plant. The total concentration of gadolinium increased significantly from 50 to 990 ng L(-1) due to the influx of the contrast agents. After complete mixing with the river water, the concentration remained constant over a distance of at least 4 km. Two main substances [Dotarem(®) (Gd-DOTA) and Gadovist(®) (Gd-BT-DO3A)] have been identified in the river water using standards. A gadolinium-based contrast agent, possibly Gd-DOTA (Dotarem(®)), was also detected in water plant samples taken from the Teltow channel. Therefore, uptake of contrast agents [Gadovist(®) (Gd-BTDO3A), Magnevist(®) (Gd-DTPA), Omniscan(®) (Gd-DTPA-BMA), Dotarem(®) (Gd-DOTA), and Multihance(®) (Gd-BOPTA)] by plants was investigated in a model experiment using Lepidium sativum (cress plants). HILIC-ICP-MS was used for identification of different contrast agents, and a first approach for quantification using aqueous standard solutions was tested. For speciation analysis, all investigated contrast agents could be extracted from the plant tissues with a recovery of about 54 % for Multihance(®) (Gd-BOPTA) up to 106 % for Gadovist(®) (Gd-BT-DO3A). These experiments demonstrate that all contrast agents investigated are transported from the roots to the leaves where the highest content was measured.

  20. 77 FR 25463 - Applications for New Awards; Enhanced Assessment Instruments Grants Program-Enhanced Assessment...

    Science.gov (United States)

    2012-04-30

    ... Instruments Grants that yield significant research, methodologies, products, or tools specifically regarding... Applications for New Awards; Enhanced Assessment Instruments Grants Program--Enhanced Assessment Instruments...: Notice. Overview Information: Enhanced Assessment Instruments Grants Program--Enhanced...

  1. The Misfortunes of Moral Enhancement.

    Science.gov (United States)

    Azevedo, Marco Antonio

    2016-10-01

    In Unfit for the Future, Ingmar Persson and Julian Savulescu present a sophisticated argument in defense of the imperative of moral enhancement. They claim that without moral enhancement, the future of humanity is seriously compromised. The possibility of ultimate harm, caused by a dreadful terrorist attack or by a final unpreventable escalation of the present environmental crisis aggravated by the availability of cognitive enhancement, makes moral enhancement a top priority. It may be considered optimistic to think that our present moral capabilities can be successfully improved by means of moral education, moral persuasion, and fear of punishment. So, without moral enhancement, drastic restrictions on human freedom would become the only alternative to prevent those dramatic potential outcomes. In this article, I will try to show that we still have reason to be less pessimistic and that Persson & Savulescu's arguments are fortunately unconvincing. © The Author 2016. Published by Oxford University Press, on behalf of the Journal of Medicine and Philosophy Inc. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  2. Enhanced sludge washing evaluation plan

    Energy Technology Data Exchange (ETDEWEB)

    Jensen, R.D.

    1994-09-01

    The Tank Waste Remediation System (TWRS) Program mission is to store, treat, and immobilize highly radioactive Hanford Site waste (current and future tank waste and the strontium/cesium capsules) in an environmentally sound, safe, and cost-effective manner. The scope of the TWRS Waste Pretreatment Program is to treat tank waste and separate that waste into HLW and LLW fractions and provide additional treatment as required to feed LLW and HLW immobilization facilities. Enhanced sludge washing was chosen as the baseline process for separating Hanford tank waste sludge. Section 1.0 briefly discusses the purpose of the evaluation plan and provides the background that led to the choice of enhanced sludge washing as the baseline process. Section 2.0 provides a brief summary of the evaluation plan details. Section 3.0 discusses, in some detail, the technical work planned to support the evaluation of enhanced sludge washing. Section 4.0 briefly discusses the potential important of policy issues to the evaluation. Section 5.0 discusses the methodology to be used in the evaluation process. Section 6.0 summarizes the milestones that have been defined to complete the enhanced sludge washing evaluation and provides a summary schedule to evaluate the performance of enhanced sludge washing. References are identified in Section 7.0, and additional schedule and milestone information is provided in the appendices.

  3. The application of Gadopentate-Dimeneglumin has no impact on progression free and overall survival as well as renal function in patients with monoclonal plasma cell disorders if general precautions are taken

    Energy Technology Data Exchange (ETDEWEB)

    Hillengass, J. [University of Heidelberg, Department of Hematology, Oncology and Rheumatology, Heidelberg (Germany); German Cancer Research Center Heidelberg, Department of Radiology, Heidelberg (Germany); Stoll, J.; Wagner, B.; Goldschmidt, H. [University of Heidelberg, Department of Hematology, Oncology and Rheumatology, Heidelberg (Germany); Zechmann, C.M. [Rinecker Proton Therapy Center, Munich (Germany); Kunz, C.; Heiss, C. [German Cancer Research Center Heidelberg, Department of Biostatistics, Heidelberg (Germany); Sumkauskaite, M. [University of Heidelberg, Department of Radiology, Heidelberg (Germany); Moehler, T.M. [InVentiv Health Clinical, Wiesbaden (Germany); Schlemmer, H.P.; Delorme, S. [German Cancer Research Center Heidelberg, Department of Radiology, Heidelberg (Germany)

    2014-10-31

    The current analysis investigated the prognostic significance of gadopentetate dimeglumine on survival and renal function in patients with monoclonal plasma cell disorders. In this study 263 patients who had received gadopentetate dimeglumine within a prospective trial investigating dynamic contrast-enhanced magnetic resonance imaging (MRI) were compared with 335 patients who had undergone routine, unenhanced MRI. We found no significant prognostic impact of the application of contrast agent on progression-free survival in patients with either monoclonal gammopathy of undetermined significance, smouldering or symptomatic myeloma and no significant prognostic impact on overall survival in patients with symptomatic myeloma. Since renal impairment is a frequent complication of myeloma, and decreased renal function is associated with a higher risk of complications in patients receiving contrast agents, we evaluated the impact of contrast agent on renal function after 1 year. In the present analysis the only significant adverse impact on kidney function occurred in symptomatic myeloma patients who already had impaired renal parameters at baseline. Here, the renal function did not recover during therapy, whereas it did so in patients with normal or only slightly impaired renal function. If general recommendations are adhered to, gadopentetate dimeglumine can be safely applied in patients with monoclonal plasma cell disease. (orig.)

  4. Piezoelectric enhancement under negative pressure

    Science.gov (United States)

    Kvasov, Alexander; McGilly, Leo J.; Wang, Jin; Shi, Zhiyong; Sandu, Cosmin S.; Sluka, Tomas; Tagantsev, Alexander K.; Setter, Nava

    2016-07-01

    Enhancement of ferroelectric properties, both spontaneous polarization and Curie temperature under negative pressure had been predicted in the past from first principles and recently confirmed experimentally. In contrast, piezoelectric properties are expected to increase by positive pressure, through polarization rotation. Here we investigate the piezoelectric response of the classical PbTiO3, Pb(Zr,Ti)O3 and BaTiO3 perovskite ferroelectrics under negative pressure from first principles and find significant enhancement. Piezoelectric response is then tested experimentally on free-standing PbTiO3 and Pb(Zr,Ti)O3 nanowires under self-sustained negative pressure, confirming the theoretical prediction. Numerical simulations verify that negative pressure in nanowires is the origin of the enhanced electromechanical properties. The results may be useful in the development of highly performing piezoelectrics, including lead-free ones.

  5. Human enhancement: The new eugenics.

    Science.gov (United States)

    Vizcarrondo, Felipe E

    2014-08-01

    Supporters of human enhancement through genetic and other reproductive technologies claim that the new liberal eugenics, based on science and individual consent differs from the old eugenics which was unscientific and coercive. Supporters claim it is the parent's moral obligation to produce the best children possible. At this time, a defective gene that is identified in an unborn child cannot be repaired. To prevent the manifestation of the undesirable trait the unborn child is destroyed. The arguments in support of human enhancement are based on an ethic of consequence that could allow for nearly any means as long as the desired end is reached. Medical enhancement may affect the parent-child family unit; the parents' love for the child may be conditioned on the expected results. The new eugenics, although based on science, continues to pursue the same goal as the old eugenics, the development of a superior individual and the elimination of those considered inferior.

  6. Moral enhancement requires multiple virtues.

    Science.gov (United States)

    Hughes, James J

    2015-01-01

    Some of the debates around the concept of moral enhancement have focused on whether the improvement of a single trait, such as empathy or intelligence, would be a good in general, or in all circumstances. All virtue theories, however, both secular and religious, have articulated multiple virtues that temper and inform one another in the development of a mature moral character. The project of moral enhancement requires a reengagement with virtue ethics and contemporary moral psychology to develop an empirically grounded model of the virtues and a fuller model of character development. Each of these virtues may be manipulable with electronic, psychopharmaceutical, and genetic interventions. A set of interdependent virtues is proposed, along with some of the research pointing to ways such virtues could be enhanced.

  7. Plasmon-enhanced UV photocatalysis

    Energy Technology Data Exchange (ETDEWEB)

    Honda, Mitsuhiro; Saito, Yuika, E-mail: yuika@ap.eng.osaka-u.ac.jp; Kawata, Satoshi [Department of Applied Physics, Osaka University, Suita, Osaka 565-0871 (Japan); Kumamoto, Yasuaki [Nanophotonics Laboratory, RIKEN, Wako, Saitama 351-0198 (Japan); Taguchi, Atsushi [Nanophotonics Laboratory, RIKEN, Wako, Saitama 351-0198 (Japan); Department of Mechanical Systems Engineering, School of Engineering, Tokyo University of Agriculture and Technology, Koganei, Tokyo 184-8588 (Japan)

    2014-02-10

    We report plasmonic nanoparticle enhanced photocatalysis on titanium dioxide (TiO{sub 2}) in the deep-UV range. Aluminum (Al) nanoparticles fabricated on TiO{sub 2} film increases the reaction rate of photocatalysis by factors as high as 14 under UV irradiation in the range of 260–340 nm. The reaction efficiency has been determined by measuring the decolorization rate of methylene blue applied on the TiO{sub 2} substrate. The enhancement of photocatalysis shows particle size and excitation wavelength dependence, which can be explained by the surface plasmon resonance of Al nanoparticles.

  8. Bibliometric-enhanced Information Retrieval

    CERN Document Server

    Mayr, Philipp; Larsen, Birger; Schaer, Philipp; Mutschke, Peter

    2013-01-01

    Bibliometric techniques are not yet widely used to enhance retrieval processes in digital libraries, although they offer value-added effects for users. In this workshop we will explore how statistical modelling of scholarship, such as Bradfordizing or network analysis of coauthorship network, can improve re-trieval services for specific communities, as well as for large, cross-domain col-lections. This workshop aims to raise awareness of the missing link between in-formation retrieval (IR) and bibliometrics/scientometrics and to create a common ground for the incorporation of bibliometric-enhanced services into retrieval at the digital library interface.

  9. Perturbations can enhance qauntum search

    CERN Document Server

    Bae, J; Bae, Joonwoo; Kwon, Younghun

    2003-01-01

    In general, a quantum algorithm wants to avoid decoherence or perturbation, since such factors may cause errors in the algorithm. In this letter, we will supply the answer to the interesting question: can the factors seemingly harmful to a quantum algorithm(for example, perturbations) enhance the algorithm? We show that some perturbations to the generalized quantum search Hamiltonian can reduce the running time and enhance the success probability. We also provide the narrow bound to the perturbation which can be beneficial to quantum search. In addition, we show that the error induced by a perturbation on the Farhi and Gutmann Hamiltonian can be corrected by another perturbation.

  10. Effect of alcohols and enhancers on permeation enhancement of ketorolac

    Directory of Open Access Journals (Sweden)

    Chandra Amrish

    2009-01-01

    Full Text Available A reservoir-type transdermal patch for the delivery of ketorolac was studied. The low permeability of the skin is the rate-limiting step for delivery of most of the drugs. Studies were carried out to investigate the effect of pH, alcohols, and chemical permeation enhancers on the in vitro permeation of ketorolac. The reservoir core of the transdermal patch was filled with the hydrogel of a nonionic polymer, methocel K 15 M (hydroxyl propyl methylcellulose, HPMC formulated at an optimized pH of 5.4. Enhanced in vitro permeation was achieved after the incorporation of the alcohols. Higher enhancement was produced by short-chain alcohols like ethanol and isopropyl alcohol (IPA. Propylene glycol (PG along with other alcohols, viz. n-propanol, n-butanol, and n-pentanol, lagged behind. An exponential rise in permeation was observed in flux with an increase in the concentration of IPA. At 25%w/w IPA concentration, the observed ketorolac flux was 18.04mg/cm 2 /h. Terpene containing eucalyptus oil was studied to determine its permeation enhancement capability. The increase in the concentration of eucalyptus oil enhanced the drug permeation and a maximum flux of 66.38 and 90.56mg/cm 2 /h was achieved at 10 and 15%w/w concentrations. The anti-inflammatory potential of the transdermal formulation was evaluated on a carrageenan-induced paw edema model, with 41.67% inhibition at 6 h. The skin irritation potential was evaluated by the Drazie test and the formulations prepared were found to be safe. The reservoir-type transdermal patch for the delivery of ketorolac appeared to be feasible for delivering ketorolac across the skin.

  11. Advances in heat transfer enhancement

    CERN Document Server

    Saha, Sujoy Kumar; Sundén, Bengt; Wu, Zan

    2016-01-01

    This Brief addresses the phenomena of heat transfer enhancement. A companion edition in the SpringerBrief Subseries on Thermal Engineering and Applied Science to three other monographs including “Critical Heat Flux in Flow Boiling in Microchannels,” this volume is idea for professionals, researchers, and graduate students concerned with electronic cooling.

  12. Dimensional enhancement of kinetic energies

    DEFF Research Database (Denmark)

    Schleich, W.P.; Dahl, Jens Peder

    2002-01-01

    Simple thermodynamics considers kinetic energy to be an extensive variable which is proportional to the number N of particles. We present a quantum state of N noninteracting particles for which the kinetic energy increases quadratically with N. This enhancement effect is tied to the quantum centr...

  13. Managing to enhance soil health

    Science.gov (United States)

    Healthy soils are critical for meeting current and future societal demands. Management strategies that protect the soil against erosion, build soil organic matter and promote nutrient cycling are ways to enhance soil health. Keeping soils covered and judicious use of agrochemicals are akin to us “hu...

  14. Genomic Signal Enhancement by Clustering

    Institute of Scientific and Technical Information of China (English)

    ZHENG Wei-Mou

    2003-01-01

    Weight matrix models for signal sequence motif are simple. A main limitation of the models is the assumption of independence between positions. Signal enhancement is achieved by taking the total likelihood as the objective function for maximization to cluster sequences into groups with different patterns. As an example, the initial and terminal signals for translation in rice genome are examined.

  15. Enhancing hydrogen spillover and storage

    Science.gov (United States)

    Yang, Ralph T.; Li, Yingwel; Lachawiec, Jr., Anthony J.

    2011-05-31

    Methods for enhancing hydrogen spillover and storage are disclosed. One embodiment of the method includes doping a hydrogen receptor with metal particles, and exposing the hydrogen receptor to ultrasonification as doping occurs. Another embodiment of the method includes doping a hydrogen receptor with metal particles, and exposing the doped hydrogen receptor to a plasma treatment.

  16. Enhancing Access to Journal Literature.

    Science.gov (United States)

    Maine Univ., Orono. Raymond H. Fogler Library.

    The libraries of the University of Maine System, Bates, Bowdoin, and Colby Colleges have installed integrated systems which are being linked electronically and are designed to promote the maximum sharing of library resources, thereby significantly enhancing the teaching and research capabilities of each institution. The institutions propose to…

  17. Surface-enhanced Raman nanodomes

    Energy Technology Data Exchange (ETDEWEB)

    Choi, Charles J; Xu Zhida; Wu, Hsin-Yu; Liu, Gang Logan; Cunningham, Brian T, E-mail: bcunning@illinois.edu [Department of Electrical and Computer Engineering, Micro and Nanotechnology Laboratory, University of Illinois at Urbana-Champaign, 208 North Wright Street, Urbana, IL 61801 (United States)

    2010-10-15

    We demonstrate a surface-enhanced Raman scattering (SERS) substrate consisting of a closely spaced metal nanodome array fabricated on flexible plastic film. We used a low-cost, large-area replica molding process to produce a two-dimensional periodic array of cylinders that is subsequently overcoated with SiO{sub 2} and silver thin films to form dome-shaped structures. Finite element modeling was used to investigate the electromagnetic field distribution of the nanodome array structure and the effect of the nanodome separation distance on the electromagnetic field enhancement. The SERS enhancement from the nanodome array substrates was experimentally verified using rhodamine 6G as the analyte. With a separation distance of 17 nm achieved between adjacent domes using a process that is precisely controlled during thin film deposition, a reproducible SERS enhancement factor of 1.37 x 10{sup 8} was demonstrated. The nanoreplica molding process presented in this work allows for simple, low-cost, high-throughput fabrication of uniform nanoscale SERS substrates over large surface areas without the requirement for high resolution lithography or defect-free deposition of spherical microparticle monolayer templates.

  18. Enhancements to PVM's BEOLIN architecture

    Science.gov (United States)

    Springer, Paul L.

    2005-01-01

    .4.3 of PVM had previously been enhanced by the addition of a new architecture, BEOLIN, which allowed a PVM user to abstract a Beowulf class computer with a private network to appear as a single system, visible to the outside world, which could spawn tasks on different internal nodes.

  19. Enhancing hydrogen spillover and storage

    Science.gov (United States)

    Yang, Ralph T; Li, Yingwei; Lachawiec, Jr., Anthony J

    2013-02-12

    Methods for enhancing hydrogen spillover and storage are disclosed. One embodiment of the method includes doping a hydrogen receptor with metal particles, and exposing the hydrogen receptor to ultrasonication as doping occurs. Another embodiment of the method includes doping a hydrogen receptor with metal particles, and exposing the doped hydrogen receptor to a plasma treatment.

  20. to enhance re-election

    African Journals Online (AJOL)

    PROF. O. E. OSUAGWU

    2013-12-01

    Dec 1, 2013 ... Assessing the Impact of Information Technology (WWW) on the attainment of Positive Corporate Image (PCI) to enhance re-election bid of incumbent ... public legitimacy and influence electoral victory at the polls. .... recognized main media and subdivision for ..... To avoid social and political conflicts,.

  1. Controlling plasmon-enhanced luminescence

    NARCIS (Netherlands)

    Mertens, H.

    2007-01-01

    Plasmons are collective oscillations of the free electrons in a metal or an ionized gas. Plasmons dominate the optical properties of noble-metal nanoparticles, which enables a variety of applications. This thesis focuses on plasmon-enhanced luminescence of silicon quantum dots (Si QDs) and optically

  2. CPS Science Laboratory Enhancement Project

    Energy Technology Data Exchange (ETDEWEB)

    James, Chandra

    2014-12-03

    The lab enhancement initiative was designed to support early implementation efforts of new policy to promote safe learning environments and school labs called the Chemical Safety and Hygiene Plan (CSHP). These efforts included comprehensive inventories and chemical removals at all Chicago Public High Schools, conducted by environmental health and safety consultants, and the development of professional development resources for teachers.

  3. Bubble chamber: colour enhanced tracks

    CERN Multimedia

    1998-01-01

    This artistically-enhanced image of real particle tracks was produced in the Big European Bubble Chamber (BEBC). Liquid hydrogen is used to create bubbles along the paths of the particles as a piston expands the medium. A magnetic field is produced in the detector causing the particles to travel in spirals, allowing charge and momentum to be measured.

  4. Progress in Diffraction Enhanced Imaging

    Institute of Scientific and Technical Information of China (English)

    2004-01-01

    @@ In cooperation with the Topography Station of Beijing Synchrotron Radiation under CAS Institute of High Energy Physics, a research group from the CAS Shanghai Institute of Optics and Fine Mechanics (SIOM) has made encouraging progress in the diffraction enhanced imaging technology through phase-contrast microscope by hard X-rays.

  5. Enhancing Author's Voice through Scripting

    Science.gov (United States)

    Young, Chase J.; Rasinski, Timothy V.

    2011-01-01

    The authors suggest using scripting as a strategy to mentor and enhance author's voice in writing. Through gradual release, students use authentic literature as a model for writing with voice. The authors also propose possible extensions for independent practice, integration across content areas, and tips for evaluation.

  6. Forensics: Enhancing Civic Literacy & Democracy

    Science.gov (United States)

    Briscoe, Shawn F.

    2009-01-01

    Forensics--interpretation, speech, and debate--can and should be a meaningful part of every school's curriculum. To put it simply, the course of study, alongside cocurricular competition, promotes civic education and enhances the standard curriculum by helping students explore myriad topics from multiple angles and find the truth in each,…

  7. Contrast enhancement in light microscopy.

    Science.gov (United States)

    Ernst Keller, H; Watkins, Simon

    2013-01-01

    The optical microscope is a fundamental component of an image cytometry system. This unit covers the basic concepts of light microscopy, including Köhler illumination, resolution, contrast, and numerical aperture, and reviews the many types of instruments and techniques for contrast enhancement.

  8. Bibliometric-enhanced information retrieval

    NARCIS (Netherlands)

    Mayr, Philipp; Scharnhorst, Andrea; Larsen, Birger; Schaer, Philipp; Mutschke, Peter

    2014-01-01

    Bibliometric techniques are not yet widely used to enhance retrieval processes in digital libraries, although they offer value-added effects for users. In this workshop we will explore how statistical modelling of scholarship, such as Bradfordizing or network analysis of coauthorship network, can im

  9. Contrast-enhanced peripheral MRA

    DEFF Research Database (Denmark)

    Nielsen, Yousef W; Thomsen, Henrik S

    2012-01-01

    In the last decade contrast-enhanced magnetic resonance angiography (CE-MRA) has gained wide acceptance as a valuable tool in the diagnostic work-up of patients with peripheral arterial disease. This review presents current concepts in peripheral CE-MRA with emphasis on MRI technique and contrast...

  10. Subendometrial enhancement and peritumoral enhancement for assessing endometrial cancer on dynamic contrast enhanced MR imaging

    Energy Technology Data Exchange (ETDEWEB)

    Fujii, Shinya [Division of Radiology, Department of Pathophysiological and Therapeutic Science, Faculty of Medicine, Tottori University, Yonago (Japan); Department of Diagnostic Imaging and Nuclear Medicine, Graduate School of Medicine, Kyoto University, Kyoto (Japan); Kido, Aki, E-mail: akikido@kuhp.kyoto-u.ac.jp [Department of Diagnostic Imaging and Nuclear Medicine, Graduate School of Medicine, Kyoto University, Kyoto (Japan); Baba, Tsukasa [Departments of Gynecology and Obstetrics, Graduate School of Medicine, Kyoto University, Kyoto (Japan); Fujimoto, Koji; Daido, Sayaka [Department of Diagnostic Imaging and Nuclear Medicine, Graduate School of Medicine, Kyoto University, Kyoto (Japan); Matsumura, Noriomi; Konishi, Ikuo [Departments of Gynecology and Obstetrics, Graduate School of Medicine, Kyoto University, Kyoto (Japan); Togashi, Kaori [Department of Diagnostic Imaging and Nuclear Medicine, Graduate School of Medicine, Kyoto University, Kyoto (Japan)

    2015-04-15

    Highlights: •We have assessed the peritumoral enhancement (PTE), which mimics SEE on DCE. •We evaluated the diagnostic accuracy of SEE for the myometrial invasion and the frequency of PTE. •We assessed the relationship between these enhancements and important pathologic factors. •PTE Type 1 is the main factor causing the overestimation of myometrial invasion using SEE on DCE. •PTE Type 2 correlates the myometrial invasion and may play an important role in the diagnosis of LVSI. -- Abstract: Objectives: To evaluate the diagnostic accuracy of subendometrial enhancement (SEE) in assessing the myometrial invasion in endometrial cancer, the frequency and clinical significance of peritumoral enhancement (PTE) on dynamic contrast enhanced (DCE) imaging. Materials and methods: MR images of 147 patients with endometrial cancer were retrospectively analyzed for intact SEE and PTEs: Type 1, a focal early enhancement peritumorally, and Type 2, an irregular thin-layered early intense enhancement peritumorally. Two radiologists independently assessed intact SEE and PTEs on DCE imaging and compared the lesions by the presence and depth of myometrial invasion, grade, lymphovascular space involvement (LVSI), and lymph node metastasis. The relationship between SEE, PTEs, and each factor was analyzed using univariate and multivariate analyses. The sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and diagnostic accuracy were calculated for SEE. Results: The sensitivity, specificity, PPV, NPV and diagnostic accuracy for myometrial invasion based on SEE disruption on DCE were 96.6%, 32.1–46.4%, 85.8–88.5%, 69.2–76.5%, and 84.4–87.1%. According to multivariate analysis, SEE significantly predicted myometrial invasion (p < 0.0001). PTE Type 2 significantly predicted myometrial invasion presence (p < 0.05) and depth (p < 0.01). Conclusion: Diagnosis of myometrial invasion only by using SEE might be difficult on DCE-MRI due to the

  11. Image enhancement method for fingerprint recognition system.

    Science.gov (United States)

    Li, Shunshan; Wei, Min; Tang, Haiying; Zhuang, Tiange; Buonocore, Michael

    2005-01-01

    Image enhancement plays an important role in Fingerprint Recognition System. In this paper fingerprint image enhancement method, a refined Gabor filter, is presented. This enhancement method can connect the ridge breaks, ensures the maximal gray values located at the ridge center and has the ability to compensate for the nonlinear deformations. The result shows it can improve the performance of image enhancement.

  12. Blob-enhanced reconstruction technique

    Science.gov (United States)

    Castrillo, Giusy; Cafiero, Gioacchino; Discetti, Stefano; Astarita, Tommaso

    2016-09-01

    A method to enhance the quality of the tomographic reconstruction and, consequently, the 3D velocity measurement accuracy, is presented. The technique is based on integrating information on the objects to be reconstructed within the algebraic reconstruction process. A first guess intensity distribution is produced with a standard algebraic method, then the distribution is rebuilt as a sum of Gaussian blobs, based on location, intensity and size of agglomerates of light intensity surrounding local maxima. The blobs substitution regularizes the particle shape allowing a reduction of the particles discretization errors and of their elongation in the depth direction. The performances of the blob-enhanced reconstruction technique (BERT) are assessed with a 3D synthetic experiment. The results have been compared with those obtained by applying the standard camera simultaneous multiplicative reconstruction technique (CSMART) to the same volume. Several blob-enhanced reconstruction processes, both substituting the blobs at the end of the CSMART algorithm and during the iterations (i.e. using the blob-enhanced reconstruction as predictor for the following iterations), have been tested. The results confirm the enhancement in the velocity measurements accuracy, demonstrating a reduction of the bias error due to the ghost particles. The improvement is more remarkable at the largest tested seeding densities. Additionally, using the blobs distributions as a predictor enables further improvement of the convergence of the reconstruction algorithm, with the improvement being more considerable when substituting the blobs more than once during the process. The BERT process is also applied to multi resolution (MR) CSMART reconstructions, permitting simultaneously to achieve remarkable improvements in the flow field measurements and to benefit from the reduction in computational time due to the MR approach. Finally, BERT is also tested on experimental data, obtaining an increase of the

  13. Enhancing who? Enhancing what? Ethics, bioethics, and transhumanism.

    Science.gov (United States)

    Koch, Tom

    2010-12-01

    Transhumanists advance a "posthuman" condition in which technological and genetic enhancements will transform humankind. They are joined in this goal by bioethicists arguing for genetic selection as a means of "enhancing evolution," improving if not also the species then at least the potential lives of future individuals. The argument of both, this paper argues, is a new riff on the old eugenics tune. As ever, it is done in the name of science and its presumed knowledge base. As ever, the result is destructive rather than instructive, bad faith promoted as high ideal. The paper concludes with the argument that species advancement is possible but in a manner thoroughly distinct from that advanced by either of these groups.

  14. Visualization and quantification of whole rat heart laminar structure using high-spatial resolution contrast-enhanced MRI.

    Science.gov (United States)

    Gilbert, Stephen H; Benoist, David; Benson, Alan P; White, Ed; Tanner, Steven F; Holden, Arun V; Dobrzynski, Halina; Bernus, Olivier; Radjenovic, Aleksandra

    2012-01-01

    It has been shown by histology that cardiac myocytes are organized into laminae and this structure is important in function, both influencing the spread of electrical activation and enabling myocardial thickening in systole by laminar sliding. We have carried out high-spatial resolution three-dimensional MRI of the ventricular myolaminae of the entire volume of the isolated rat heart after contrast perfusion [dimeglumine gadopentate (Gd-DTPA)]. Four ex vivo rat hearts were perfused with Gd-DTPA and fixative and high-spatial resolution MRI was performed on a 9.4T MRI system. After MRI, cryosectioning followed by histology was performed. Images from MRI and histology were aligned, described, and quantitatively compared. In the three-dimensional MR images we directly show the presence of laminae and demonstrate that these are highly branching and are absent from much of the subepicardium. We visualized these MRI volumes to demonstrate laminar architecture and quantitatively demonstrated that the structural features observed are similar to those imaged in histology. We showed qualitatively and quantitatively that laminar architecture is similar in the four hearts. MRI can be used to image the laminar architecture of ex vivo hearts in three dimensions, and the images produced are qualitatively and quantitatively comparable with histology. We have demonstrated in the rat that: 1) laminar architecture is consistent between hearts; 2) myolaminae are absent from much of the subepicardium; and 3) although localized orthotropy is present throughout the myocardium, tracked myolaminae are branching structures and do not have a discrete identity.

  15. Enhancing OPAC Records for Discovery

    Directory of Open Access Journals (Sweden)

    Patrick Griffis

    2009-09-01

    Full Text Available This article proposes adding keywords and descriptors to the catalog records of electronic databases and media items to enhance their discovery. The authors contend that subject liaisons can add value to OPAC records and enhance discovery of electronic databases and media items by providing searchable keywords and resource descriptions. The authors provide an examination of OPAC records at their own library, which illustrates the disparity of useful keywords and descriptions within the notes field for media item records versus electronic database records. The authors outline methods for identifying useful keywords for indexing OPAC records of electronic databases. Also included is an analysis of the advantages of using Encore’s Community Tag and Community Review features to allow subject liaisons to work directly in the catalog instead of collaborating with cataloging staff

  16. Gestures Enhance Foreign Language Learning

    Directory of Open Access Journals (Sweden)

    Manuela Macedonia

    2012-11-01

    Full Text Available Language and gesture are highly interdependent systems that reciprocally influence each other. For example, performing a gesture when learning a word or a phrase enhances its retrieval compared to pure verbal learning. Although the enhancing effects of co-speech gestures on memory are known to be robust, the underlying neural mechanisms are still unclear. Here, we summarize the results of behavioral and neuroscientific studies. They indicate that the neural representation of words consists of complex multimodal networks connecting perception and motor acts that occur during learning. In this context, gestures can reinforce the sensorimotor representation of a word or a phrase, making it resistant to decay. Also, gestures can favor embodiment of abstract words by creating it from scratch. Thus, we propose the use of gesture as a facilitating educational tool that integrates body and mind.

  17. Enhanced responsivity resonant RF photodetectors.

    Science.gov (United States)

    Liu, R; Dev, S; Zhong, Y; Lu, R; Streyer, W; Allen, J W; Allen, M S; Wenner, B R; Gong, S; Wasserman, D

    2016-11-14

    The responsivity of room-temperature, semiconductor-based photodetectors consisting of resonant RF circuits coupled to microstrip buslines is investigated. The dependence of the photodetector response on the semiconductor material and RF circuit geometry is presented, as is the detector response as a function of the spatial position of the incident light. We demonstrate significant improvement in detector response by choice of photoconductive material, and for a given material, by positioning our optical signal to overlap with positions of RF field enhancement. Design of RF circuits with strong field enhancement are demonstrated to further improve detector response. The improved detector response demonstrated offers opportunities for applications in RF photonics, materials metrology, or single read-out multiplexed detector arrays.

  18. Personalization enhances learning anatomy terms.

    Science.gov (United States)

    Ginns, Paul; Fraser, Jennifer

    2010-01-01

    Personalizing computer-based instructional text with a conversational rather than formal style has been found to enhance learning substantially. An experimental study investigated whether a conversational style would enhance learning anatomy terminology from paper-based materials. Students were randomly assigned to experimental conditions, and hypotheses were tested with a multiple-choice test and self-report scales. Studying personalized materials led to better performance on a terminology test and lower mental effort during testing than studying non-personalized materials. However, groups did not differ on ratings of interest/enjoyment. These results extend previous research by demonstrating learning gains following personalization using paper-based materials. However, the lack of effect on interest/enjoyment self-reports raises questions about previous theorizing on the role of this variable.

  19. Quantum-Enhanced Machine Learning.

    Science.gov (United States)

    Dunjko, Vedran; Taylor, Jacob M; Briegel, Hans J

    2016-09-23

    The emerging field of quantum machine learning has the potential to substantially aid in the problems and scope of artificial intelligence. This is only enhanced by recent successes in the field of classical machine learning. In this work we propose an approach for the systematic treatment of machine learning, from the perspective of quantum information. Our approach is general and covers all three main branches of machine learning: supervised, unsupervised, and reinforcement learning. While quantum improvements in supervised and unsupervised learning have been reported, reinforcement learning has received much less attention. Within our approach, we tackle the problem of quantum enhancements in reinforcement learning as well, and propose a systematic scheme for providing improvements. As an example, we show that quadratic improvements in learning efficiency, and exponential improvements in performance over limited time periods, can be obtained for a broad class of learning problems.

  20. Microbial enhanced oil recovery (MEOR).

    Science.gov (United States)

    Brown, Lewis R

    2010-06-01

    Two-thirds of the oil ever found is still in the ground even after primary and secondary production. Microbial enhanced oil recovery (MEOR) is one of the tertiary methods purported to increase oil recovery. Since 1946 more than 400 patents on MEOR have been issued, but none has gained acceptance by the oil industry. Most of the literature on MEOR is from laboratory experiments or from field trials of insufficient duration or that lack convincing proof of the process. Several authors have made recommendations required to establish MEOR as a viable method to enhance oil recovery, and until these tests are performed, MEOR will remain an unproven concept rather than a highly desirable reality. Copyright 2010 Elsevier Ltd. All rights reserved.

  1. Renormalization algorithm with graph enhancement

    CERN Document Server

    Hübener, R; Hartmann, L; Dür, W; Plenio, M B; Eisert, J

    2011-01-01

    We present applications of the renormalization algorithm with graph enhancement (RAGE). This analysis extends the algorithms and applications given for approaches based on matrix product states introduced in [Phys. Rev. A 79, 022317 (2009)] to other tensor-network states such as the tensor tree states (TTS) and projected entangled pair states (PEPS). We investigate the suitability of the bare TTS to describe ground states, showing that the description of certain graph states and condensed matter models improves. We investigate graph-enhanced tensor-network states, demonstrating that in some cases (disturbed graph states and for certain quantum circuits) the combination of weighted graph states with tensor tree states can greatly improve the accuracy of the description of ground states and time evolved states. We comment on delineating the boundary of the classically efficiently simulatable states of quantum many-body systems.

  2. Quantum-Enhanced Machine Learning

    Science.gov (United States)

    Dunjko, Vedran; Taylor, Jacob M.; Briegel, Hans J.

    2016-09-01

    The emerging field of quantum machine learning has the potential to substantially aid in the problems and scope of artificial intelligence. This is only enhanced by recent successes in the field of classical machine learning. In this work we propose an approach for the systematic treatment of machine learning, from the perspective of quantum information. Our approach is general and covers all three main branches of machine learning: supervised, unsupervised, and reinforcement learning. While quantum improvements in supervised and unsupervised learning have been reported, reinforcement learning has received much less attention. Within our approach, we tackle the problem of quantum enhancements in reinforcement learning as well, and propose a systematic scheme for providing improvements. As an example, we show that quadratic improvements in learning efficiency, and exponential improvements in performance over limited time periods, can be obtained for a broad class of learning problems.

  3. Superhydrophobicity enhancement through substrate flexibility.

    Science.gov (United States)

    Vasileiou, Thomas; Gerber, Julia; Prautzsch, Jana; Schutzius, Thomas M; Poulikakos, Dimos

    2016-11-22

    Inspired by manifestations in nature, microengineering and nanoengineering of synthetic materials to achieve superhydrophobicity has been the focus of much work. Generally, hydrophobicity is enhanced through the combined effects of surface texturing and chemistry; being durable, rigid materials are the norm. However, many natural and technical surfaces are flexible, and the resulting effect on hydrophobicity has been largely ignored. Here, we show that the rational tuning of flexibility can work synergistically with the surface microtexture or nanotexture to enhance liquid repellency performance, characterized by impalement and breakup resistance, contact time reduction, and restitution coefficient increase. Reduction in substrate areal density and stiffness imparts immediate acceleration and intrinsic responsiveness to impacting droplets (∼350 × g), mitigating the collision and lowering the impalement probability by ∼60% without the need for active actuation. Furthermore, we exemplify the above discoveries with materials ranging from man-made (thin steel or polymer sheets) to nature-made (butterfly wings).

  4. Biosurfactant-enhanced soil bioremediation

    Energy Technology Data Exchange (ETDEWEB)

    Kosaric, N.; Lu, G.; Velikonja, J. [Univ. of Western Ontario, London, Ontario (Canada)

    1995-12-01

    Bioremediation of soil contaminated with organic chemicals is a viable alternative method for clean-up and remedy of hazardous waste sites. The final objective in this approach is to convert the parent toxicant into a readily biodegradable product which is harmless to human health and/or the environment. Biodegradation of hydrocarbons in soil can also efficiently be enhanced by addition or in-situ production of biosufactants. It was generally observed that the degradation time was shortened and particularly the adaptation time for the microbes. More data from our laboratories showed that chlorinated aromatic compounds, such as 2,4-dichlorophenol, a herbicide Metolachlor, as well as naphthalene are degraded faster and more completely when selected biosurfactants are added to the soil. More recent data demonstrated an enhanced biodegradation of heavy hydrocarbons in petrochemical sludges, and in contaminated oil when biosurfactants were present or were added prior to the biodegradation process.

  5. Photodetector with enhanced light absorption

    Science.gov (United States)

    Kane, James

    1985-01-01

    A photodetector including a light transmissive electrically conducting layer having a textured surface with a semiconductor body thereon. This layer traps incident light thereby enhancing the absorption of light by the semiconductor body. A photodetector comprising a textured light transmissive electrically conducting layer of SnO.sub.2 and a body of hydrogenated amorphous silicon has a conversion efficiency about fifty percent greater than that of comparative cells. The invention also includes a method of fabricating the photodetector of the invention.

  6. Technology Education Professional Enhancement Project

    Science.gov (United States)

    Hughes, Thomas A., Jr.

    1996-01-01

    The two goals of this project are: the use of integrative field of aerospace technology to enhance the content and instruction delivered by math, science, and technology teachers through the development of a new publication entitled NASA Technology Today, and to develop a rationale and structure for the study of technology, which establishes the foundation for developing technology education standards and programs of the future.

  7. Decision Rules for Enhanced Breakout.

    Science.gov (United States)

    1987-03-20

    347AD-A18 2753 DECISION RULES FOR ENHANCED GRERICOUT(U) MODERN TECNOLOGIES CORP DAYTON 0ON T MI MCCANN 20 MAR 87 MTC-TR-8883-02 BRMC-85-564-i F33615... information to develop a priori estimates of the cost to break-out specific spare parts. In addition, some recommendations were to be developed...implementing directives. Applicable AF and AFLC Regulations and Pamphlets were also reviewed to obtain information on costs and their estimated

  8. Enhanced heat transfer using nanofluids

    Science.gov (United States)

    Choi, Stephen U. S.; Eastman, Jeffrey A.

    2001-01-01

    This invention is directed to a method of and apparatus for enhancing heat transfer in fluids such as deionized water. ethylene glycol, or oil by dispersing nanocrystalline particles of substances such as copper, copper oxide, aluminum oxide, or the like in the fluids. Nanocrystalline particles are produced and dispersed in the fluid by heating the substance to be dispersed in a vacuum while passing a thin film of the fluid near the heated substance. The fluid is cooled to control its vapor pressure.

  9. Enhancing Soundtracks From Old Movies

    Science.gov (United States)

    Frazer, Robert E.

    1992-01-01

    Proposed system enhances soundtracks of old movies. Signal on optical soundtrack of film digitized and processed to reduce noise and improve quality; timing signals added, and signal recorded on compact disk. Digital comparator and voltage-controlled oscillator synchronizes speed of film-drive motor and compact disk motor. Frame-coded detector reads binary frame-identifying marks on film. Digital comparator generates error signal if marks on film do not match those on compact disk.

  10. Threshold enhancement of diphoton resonances

    Directory of Open Access Journals (Sweden)

    Aoife Bharucha

    2016-10-01

    Full Text Available We revisit a mechanism to enhance the decay width of (pseudo-scalar resonances to photon pairs when the process is mediated by loops of charged fermions produced near threshold. Motivated by the recent LHC data, indicating the presence of an excess in the diphoton spectrum at approximately 750 GeV, we illustrate this threshold enhancement mechanism in the case of a 750 GeV pseudoscalar boson A with a two-photon decay mediated by a charged and uncolored fermion having a mass at the 12MA threshold and a small decay width, <1 MeV. The implications of such a threshold enhancement are discussed in two explicit scenarios: i the Minimal Supersymmetric Standard Model in which the A state is produced via the top quark mediated gluon fusion process and decays into photons predominantly through loops of charginos with masses close to 12MA and ii a two Higgs doublet model in which A is again produced by gluon fusion but decays into photons through loops of vector-like charged heavy leptons. In both these scenarios, while the mass of the charged fermion has to be adjusted to be extremely close to half of the A resonance mass, the small total widths are naturally obtained if only suppressed three-body decay channels occur. Finally, the implications of some of these scenarios for dark matter are discussed.

  11. Dispersion-Enhanced Laser Gyroscope

    Science.gov (United States)

    Smith, David D.; Chang, Hongrok; Arissian, L.; Diels, J. C.

    2008-01-01

    We analyze the effect of a highly dispersive element placed inside a modulated optical cavity on the frequency and amplitude of the output modulation to determine the conditions for enhanced gyroscopic sensitivities. The element is treated as both a phase and amplitude filter, and the time-dependence of the cavity field is considered. Both atomic gases (two-level and multi-level) and optical resonators (single and coupled) are considered and compared as dispersive elements. We find that it is possible to simultaneously enhance the gyro scale factor sensitivity and suppress the dead band by using an element with anomalous dispersion that has greater loss at the carrier frequency than at the side-band frequencies, i.e., an element that simultaneously pushes and intensifies the perturbed cavity modes, e.g. a two-level absorber or an under-coupled optical resonator. The sensitivity enhancement is inversely proportional to the effective group index, becoming infinite at a group index of zero. However, the number of round trips required to reach a steady-state also becomes infinite when the group index is zero (or two). For even larger dispersions a steady-state cannot be achieved, and nonlinear dynamic effects such as bistability and periodic oscillations are predicted in the gyro response.

  12. Contrast-enhanced digital mammography

    Energy Technology Data Exchange (ETDEWEB)

    Dromain, Clarisse [Department of Radiology, Institut Gustave-Roussy, 39, rue Camille Desmoulins, 94805 Villejuif Cedex (France)], E-mail: dromain@igr.fr; Balleyguier, Corinne; Adler, Ghazal [Department of Radiology, Institut Gustave-Roussy, 39, rue Camille Desmoulins, 94805 Villejuif Cedex (France); Garbay, Jean Remi [Department of Surgery, Institut Gustave-Roussy, 39, rue Camille Desmoulins, 94805 Villejuif Cedex (France); Delaloge, Suzette [Department of Medicine, Institut Gustave-Roussy, 39, rue Camille Desmoulins, 94805 Villejuif Cedex (France)

    2009-01-15

    CEDM is a recent development of digital mammography using the intra-venous injection of an iodinated contrast agent in conjunction with a mammography examination. Two techniques have been developed to perform CEDM examinations: the temporal subtraction technique with acquisition of high-energy images before and after contrast medium injection and the dual energy technique with acquisition of a pair of low and high-energy images only after contrast medium injection. The temporal subtraction technique offered the possibility to analyze the kinetic curve of enhancement of breast lesions, similarly to breast MRI. The dual energy technique do not provide information about the kinetic of tumor enhancement but allows the acquisition of multiples views of the same breast or bilateral examination and is less sensitive to patient motion than temporal CEDM. Initial clinical experience has shown the ability of CEDM to map the distribution of neovasculature induced by cancer using mammography. Moreover, previous studies have shown a superiority of MX + CEDM, either for the assessment of the probability of malignancy than for BIRADS assessment comparing to MX alone. The potential clinical applications are the clarification of mammographically equivocal lesions, the detection of occult lesions on standard mammography, particularly in dense breast, the determination of the extent of disease, the assessment of recurrent disease and the monitoring of the response to chemotherapy. CEDM should result in a simple way to enhance the detection and the characterization of breast lesions.

  13. Lateral interactions and enhanced adsorption

    Science.gov (United States)

    Rikvold, Per Arne; Deakin, Mark R.

    1991-06-01

    We extend earlier work on the effects of lateral adsorbate-adsorbate interactions in systems with two different adsorbate species to consider in detail enhanced adsorption phenomena. We give a detailed explanation of the enhancement mechanism for a lattice-gas model in thermodynamic equilibrium, and provide explicit quantitative criteria which must be satisfied by the effective lateral interactions in systems exhibiting strong, intermediate, or weak enhancement behavior. It is the examination and understanding of the topological details of the ground-state and phase diagrams of the model that allow the formulation of these criteria. The theoretically obtained criteria are supported by precise numerical calculations (transfer-matrix with strip width six) of adsorption isotherms for a three-state lattice-gas model with nearest-neighbor interactions on a triangular lattice. The applicability of this theoretical framework is illustrated by an analysis of experimental adsorption isotherms for the electrochemical adsorption of naphthalene on copper and n-decylamine on nickel, previously obtained by Bockris et al. As suggested by Damaskin et al. we attribute the potential dependence of the organic coverage to the influence of coadsorbed hydrogen. We find that nonlinear least-squares fits of numerical lattice-gas isotherms to the experimental data produce good agreement between the experimental and numerical adsorption isotherms, as well as effective lattice-gas interaction energies consistent with independent estimates from the literature.

  14. Dispersion-enhanced laser gyroscope

    Science.gov (United States)

    Smith, David D.; Chang, Hongrok; Arissian, L.; Diels, J. C.

    2008-11-01

    We analyze the effect of a highly dispersive element placed inside a modulated optical cavity on the frequency and amplitude of the output modulation to determine the conditions for enhanced gyroscopic sensitivities. The element is treated as both a phase and amplitude filter, and the time dependence of the cavity field is considered. Both atomic gases (two level and multilevel) and optical resonators (single and coupled) are considered and compared as dispersive elements. We find that it is possible to simultaneously enhance the gyro scale factor sensitivity and suppress the dead band by using an element with anomalous dispersion that has greater loss at the carrier frequency than at the sideband frequencies, i.e., an element that simultaneously pushes and intensifies the perturbed cavity modes, e.g. a two-level absorber or an undercoupled optical resonator. The sensitivity enhancement is inversely proportional to the effective group index, becoming infinite at a group index of zero. However, the number of round trips required to reach a steady state also becomes infinite when the group index is zero (or two). For even larger dispersions a steady state cannot be achieved, and nonlinear dynamic effects such as bistability and periodic oscillations are predicted in the gyro response.

  15. Interaction Enhanced Imperialist Competitive Algorithms

    Directory of Open Access Journals (Sweden)

    Meng-Shiou Li

    2012-10-01

    Full Text Available Imperialist Competitive Algorithm (ICA is a new population-based evolutionary algorithm. It divides its population of solutions into several sub-populations, and then searches for the optimal solution through two operations: assimilation and competition. The assimilation operation moves each non-best solution (called colony in a sub-population toward the best solution (called imperialist in the same sub-population. The competition operation removes a colony from the weakest sub-population and adds it to another sub-population. Previous work on ICA focuses mostly on improving the assimilation operation or replacing the assimilation operation with more powerful meta-heuristics, but none focuses on the improvement of the competition operation. Since the competition operation simply moves a colony (i.e., an inferior solution from one sub-population to another sub-population, it incurs weak interaction among these sub-populations. This work proposes Interaction Enhanced ICA that strengthens the interaction among the imperialists of all sub-populations. The performance of Interaction Enhanced ICA is validated on a set of benchmark functions for global optimization. The results indicate that the performance of Interaction Enhanced ICA is superior to that of ICA and its existing variants.

  16. The myth of genetic enhancement.

    Science.gov (United States)

    Rosoff, Philip M

    2012-06-01

    The ongoing revolution in molecular genetics has led many to speculate that one day we will be able to change the expression or phenotype of numerous complex traits to improve ourselves in many different ways. The prospect of genetic enhancements has generated heated controversy, with proponents advocating research and implementation, with caution advised for concerns about justice, and critics tending to see the prospect of genetic enhancements as an assault on human freedom and human nature. Both camps base their arguments on the unquestioned assumption that the science will realize either their dreams or nightmares. In this paper, I show that their beliefs are based upon two fundamental mistakes. First, they are based upon an unwarranted reliance in a genetic determinism that takes for granted that the traits that we might most want to enhance, like intelligence, aggression, shyness, and even athletic ability, can be causally directed by specific genes. In so doing, character descriptions are reified to be concrete and discrete entities, in this case, genes. Second, they have accepted on faith that there is, or will be, a science to translate their hopes or worries into reality when, in fact, that is unlikely to occur because of the irreducible complexity of phenotypic expression.

  17. Proposal for Two Enhanced NTRU

    Directory of Open Access Journals (Sweden)

    Ahmed Tariq Sadiq

    2014-06-01

    Full Text Available Sound is very widely used in communication. In order to ensure secure communication a cryptographic data scheme is used. Secure sound is needed in many fields such as military, business, banking and electronic commerce. There is also an increasing demand for secured sound in network communication. Several symmetric and asymmetric algorithms are used for sound encryption. In this work, NTRU, the last in line public key cryptosystem is enhanced in two methods and used for encrypting sound files after converting the sound into text. In the proposed methods the message is encrypted one character at a time, since NTRU encrypts only prime numbers, thus 7 bits of each character is encrypted and the eighth bit is left without encryption. In method I NTRU algorithm is enhanced by adding the result obtained from calculating a mathematical equation of one variable to the message and then the resulted encrypted bit is fed-back and added to the next bit of the message in the next step; this procedure is repeated for the subsequent bits of the message. In method II NTRU algorithm is enhanced by adding the subsequent states of LFSR (Linear Feedback Shift Register to the subsequent bytes of the message. The proposed methods are tested on several sound files; the results show that the proposed methods I and II maintain approximately the same original method encryption and decryption time while generating more complex encryption.

  18. Plasmonics Enhanced Smartphone Fluorescence Microscopy

    KAUST Repository

    Wei, Qingshan

    2017-05-12

    Smartphone fluorescence microscopy has various applications in point-of-care (POC) testing and diagnostics, ranging from e.g., quantification of immunoassays, detection of microorganisms, to sensing of viruses. An important need in smartphone-based microscopy and sensing techniques is to improve the detection sensitivity to enable quantification of extremely low concentrations of target molecules. Here, we demonstrate a general strategy to enhance the detection sensitivity of a smartphone-based fluorescence microscope by using surface-enhanced fluorescence (SEF) created by a thin metal-film. In this plasmonic design, the samples are placed on a silver-coated glass slide with a thin spacer, and excited by a laser-diode from the backside through a glass hemisphere, generating surface plasmon polaritons. We optimized this mobile SEF system by tuning the metal-film thickness, spacer distance, excitation angle and polarization, and achieved ~10-fold enhancement in fluorescence intensity compared to a bare glass substrate, which enabled us to image single fluorescent particles as small as 50 nm in diameter and single quantum-dots. Furthermore, we quantified the detection limit of this platform by using DNA origami-based brightness standards, demonstrating that ~80 fluorophores per diffraction-limited spot can be readily detected by our mobile microscope, which opens up new opportunities for POC diagnostics and sensing applications in resource-limited-settings.

  19. Cyclosporine A enhances platelet aggregation.

    Science.gov (United States)

    Grace, A A; Barradas, M A; Mikhailidis, D P; Jeremy, J Y; Moorhead, J F; Sweny, P; Dandona, P

    1987-12-01

    In view of the reported increase in thromboembolic episodes following cyclosporine A (CyA) therapy, the effect of this drug on platelet aggregation and thromboxane A2 release was investigated. The addition of CyA, at therapeutic concentrations to platelet rich plasma from normal subjects in vitro was found to increase aggregation in response to adrenaline, collagen and ADP. Ingestion of CyA by healthy volunteers was also associated with enhanced platelet aggregation. The CyA-mediated enhancement of aggregation was further enhanced by the addition in vitro of therapeutic concentrations of heparin. Platelets from renal allograft recipients treated with CyA also showed hyperaggregability and increased thromboxane A2 release, which were most marked at "peak" plasma CyA concentration and less so at "trough" concentrations. Platelet hyperaggregability in renal allograft patients on long-term CyA therapy tended to revert towards normal following the replacement of CyA with azathioprine. Hypertensive patients with renal allografts on nifedipine therapy had normal platelet function and thromboxane release in spite of CyA therapy. These observations suggest that CyA-mediated platelet activation may contribute to the pathogenesis of the thromboembolic phenomena associated with the use of this drug. The increased release of thromboxane A2 (a vasoconstrictor) may also play a role in mediating CyA-related nephrotoxicity.

  20. Enhanced live cell imaging via photonic crystal enhanced fluorescence microscopy.

    Science.gov (United States)

    Chen, Weili; Long, Kenneth D; Yu, Hojeong; Tan, Yafang; Choi, Ji Sun; Harley, Brendan A; Cunningham, Brian T

    2014-11-21

    We demonstrate photonic crystal enhanced fluorescence (PCEF) microscopy as a surface-specific fluorescence imaging technique to study the adhesion of live cells by visualizing variations in cell-substrate gap distance. This approach utilizes a photonic crystal surface incorporated into a standard microscope slide as the substrate for cell adhesion, and a microscope integrated with a custom illumination source as the detection instrument. When illuminated with a monochromatic light source, angle-specific optical resonances supported by the photonic crystal enable efficient excitation of surface-confined and amplified electromagnetic fields when excited at an on-resonance condition, while no field enhancement occurs when the same photonic crystal is illuminated in an off-resonance state. By mapping the fluorescence enhancement factor for fluorophore-tagged cellular components between on- and off-resonance states and comparing the results to numerical calculations, the vertical distance of labelled cellular components from the photonic crystal substrate can be estimated, providing critical and quantitative information regarding the spatial distribution of the specific components of cells attaching to a surface. As an initial demonstration of the concept, 3T3 fibroblast cells were grown on fibronectin-coated photonic crystals with fluorophore-labelled plasma membrane or nucleus. We demonstrate that PCEF microscopy is capable of providing information about the spatial distribution of cell-surface interactions at the single-cell level that is not available from other existing forms of microscopy, and that the approach is amenable to large fields of view, without the need for coupling prisms, coupling fluids, or special microscope objectives.

  1. ATAMM enhancement and multiprocessor performance evaluation

    Science.gov (United States)

    Stoughton, John W.; Mielke, Roland R.; Som, Sukhamoy; Obando, Rodrigo; Malekpour, Mahyar R.; Jones, Robert L., III; Mandala, Brij Mohan V.

    1991-01-01

    ATAMM (Algorithm To Architecture Mapping Model) enhancement and multiprocessor performance evaluation is discussed. The following topics are included: the ATAMM model; ATAMM enhancement; ADM (Advanced Development Model) implementation of ATAMM; and ATAMM support tools.

  2. A Survey on Speech Enhancement Methodologies

    Directory of Open Access Journals (Sweden)

    Ravi Kumar. K

    2016-12-01

    Full Text Available Speech enhancement is a technique which processes the noisy speech signal. The aim of speech enhancement is to improve the perceived quality of speech and/or to improve its intelligibility. Due to its vast applications in mobile telephony, VOIP, hearing aids, Skype and speaker recognition, the challenges in speech enhancement have grown over the years. It is more challenging to suppress back ground noise that effects human communication in noisy environments like airports, road works, traffic, and cars. The objective of this survey paper is to outline the single channel speech enhancement methodologies used for enhancing the speech signal which is corrupted with additive background noise and also discuss the challenges and opportunities of single channel speech enhancement. This paper mainly focuses on transform domain techniques and supervised (NMF, HMM speech enhancement techniques. This paper gives frame work for developments in speech enhancement methodologies

  3. DENdb: database of integrated human enhancers

    KAUST Repository

    Ashoor, Haitham

    2015-09-05

    Enhancers are cis-acting DNA regulatory regions that play a key role in distal control of transcriptional activities. Identification of enhancers, coupled with a comprehensive functional analysis of their properties, could improve our understanding of complex gene transcription mechanisms and gene regulation processes in general. We developed DENdb, a centralized on-line repository of predicted enhancers derived from multiple human cell-lines. DENdb integrates enhancers predicted by five different methods generating an enriched catalogue of putative enhancers for each of the analysed cell-lines. DENdb provides information about the overlap of enhancers with DNase I hypersensitive regions, ChIP-seq regions of a number of transcription factors and transcription factor binding motifs, means to explore enhancer interactions with DNA using several chromatin interaction assays and enhancer neighbouring genes. DENdb is designed as a relational database that facilitates fast and efficient searching, browsing and visualization of information.

  4. Complementary surface charge for enhanced capacitive deionization

    NARCIS (Netherlands)

    Gao, X.; Porada, S.; Omosebi, A.; Liu, K.L.; Biesheuvel, P.M.; Landon, J.

    2016-01-01

    Commercially available activated carbon cloth electrodes are treated using nitric acid and ethylenediamine solutions, resulting in chemical surface charge enhanced carbon electrodes for capacitive deionization (CDI) applications. Surface charge enhanced electrodes are then configured in a CDI cel

  5. Integration of cognitive and moral enhancement

    Directory of Open Access Journals (Sweden)

    Rakić Vojin

    2012-01-01

    Full Text Available I will discuss four major perspectives on cognitive enhancement and morality: 1 cognitive enhancement is morally impermissible because humans are not supposed to alter what God has ordained or nature has shaped; 2 cognitive enhancement is our moral duty, because a cognitively upgraded human is a better human; 3 cognitive enhancement is morally permissible only if it is preceded by moral enhancement; 4 cognitive enhancement is morally permissible only if it is a means to moral enhancement. I shall argue that the first three perspectives are less cogent than the fourth. The fourth perspective integrates cognitive and moral enhancement into one whole. I will denote it by (C+M E. [Projekat Ministarstva nauke Republike Srbije, br. 41004 i 43007

  6. DENdb: database of integrated human enhancers.

    Science.gov (United States)

    Ashoor, Haitham; Kleftogiannis, Dimitrios; Radovanovic, Aleksandar; Bajic, Vladimir B

    2015-01-01

    Enhancers are cis-acting DNA regulatory regions that play a key role in distal control of transcriptional activities. Identification of enhancers, coupled with a comprehensive functional analysis of their properties, could improve our understanding of complex gene transcription mechanisms and gene regulation processes in general. We developed DENdb, a centralized on-line repository of predicted enhancers derived from multiple human cell-lines. DENdb integrates enhancers predicted by five different methods generating an enriched catalogue of putative enhancers for each of the analysed cell-lines. DENdb provides information about the overlap of enhancers with DNase I hypersensitive regions, ChIP-seq regions of a number of transcription factors and transcription factor binding motifs, means to explore enhancer interactions with DNA using several chromatin interaction assays and enhancer neighbouring genes. DENdb is designed as a relational database that facilitates fast and efficient searching, browsing and visualization of information. Database URL: http://www.cbrc.kaust.edu.sa/dendb/.

  7. Enhanced migration of seismic data

    Energy Technology Data Exchange (ETDEWEB)

    Carrion, P.M. (PPPG/UFBA, Instituto de Geociencias, Rua Gaetano Moura 123, Federacao, 40.210 Salvador, Bahia (BR))

    1990-10-01

    The so-called enhanced migration which uses diffraction tomography as the repair tool for correction of amplitudes (reflection coefficients) of migrated sections is discussed. As with any linearized procedure, diffraction tomography requires knowledge of the initial model. It is suggested that the initial model is taken as the migrated image. It will be demonstrated that diffraction tomography applied to the data residuals improves the amplitudes of the migrated images. Migration is redefined as the reconstruction of the wavefront sets of distributions (reflection interfaces), and the inversion process as tomographic correction of migrated images.

  8. Does Design Rationale Enhance Creativity?

    Directory of Open Access Journals (Sweden)

    Jing Wang

    2010-01-01

    Full Text Available Creativity and rationale are often viewed as two contrasting facets in software design. A lack in recognizing the facilitative relationship between creativity and rationale not only underestimates the benefits designers can obtain from rationale practices, but also confines the approaches that support creativity in software design. Our exploratory study provides empirical evidence of the positive correlation between rationale and creativity. Furthermore, we found that the feasibility of design alternatives and the comprehensiveness of tradeoff evaluation are critical to enhancing novelty, persuasiveness, and insightfulness. We also discuss future directions to further understand how these properties, or rationale quality in general, affects design creativity.

  9. Enhanced Master Controller Unit Tester

    Science.gov (United States)

    Benson, Patricia; Johnson, Yvette; Johnson, Brian; Williams, Philip; Burton, Geoffrey; McCoy, Anthony

    2007-01-01

    The Enhanced Master Controller Unit Tester (EMUT) software is a tool for development and testing of software for a master controller (MC) flight computer. The primary function of the EMUT software is to simulate interfaces between the MC computer and external analog and digital circuitry (including other computers) in a rack of equipment to be used in scientific experiments. The simulations span the range of nominal, off-nominal, and erroneous operational conditions, enabling the testing of MC software before all the equipment becomes available.

  10. Glucose biosensor enhanced by nanoparticles

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    Glucose biosensors have been formed with glucose oxidase (GOD) immobilized in composite immobilization membrane matrix, which is composed of hydrophobic gold, or hydrophilic gold, or hydrophobic silica nanoparticles, or the combination of gold and silica nanoparticles, and polyvinyl butyral (PVB) by a sol-gel method. The experiments show that nanoparticles can significantly enhance the catalytic activity of the immobilization enzyme. The current response can be increased from tens of nanoamperometer (nA) to thousands of nanoamperometer to the same glucose concentration, and the electrodes respond very quickly, to about 1 min. The function of nanoparticles effect on immobilization enzyme has been discussed.

  11. Glucose biosensor enhanced by nanoparticles

    Institute of Scientific and Technical Information of China (English)

    唐芳琼; 孟宪伟; 陈东; 冉均国; 郑昌琼

    2000-01-01

    Glucose biosensors have been formed with glucose oxidase (GOD) immobilized in composite immobilization membrane matrix, which is composed of hydrophobic gold, or hydro-philic gold, or hydrophobic silica nanoparticles, or the combination of gold and silica nanoparticles, and polyvinyl butyral (PVB) by a sol-gel method. The experiments show that nanoparticles can significantly enhance the catalytic activity of the immobilization enzyme. The current response can be increased from tens of nanoamperometer (nA) to thousands of nanoamperometer to the same glucose concentration, and the electrodes respond very quickly, to about 1 min. The function of nanoparticles effect on immobilization enzyme has been discussed.

  12. Enhancing the crisis management briefing.

    Science.gov (United States)

    Clark, Daniel W; Volkmann, Peter

    2005-01-01

    The Crisis Management Briefing (CMB) is a powerful and versatile crisis intervention tool, effective within a wide variety of populations, settings, and critical incidents. Initially proposed by Everly (2000), the CMB uniquely fills the factual information void following a critical incident. Additionally, a CMB provides essential information on effective coping strategies and available helping resources, tailored to the specific incident(s). The authors expand on the original CMB construct using their combined field experience, offering recommendations on team composition, strategic planning factors, using CISDs vs. CMBs, and specific enhancements for the four phases. They conclude with examples of specific interventions across a variety of events to illustrate their recommendations.

  13. Mutual Workshops enhancing Curriculum Integration

    DEFF Research Database (Denmark)

    Bjerregaard Jensen, Lotte; Markvorsen, Steen; Almegaard, Henrik

    2011-01-01

    -semester project in structural design was realized for the first time in autumn 2009. This paper presents the lessons learned from this first round along with the changes they inspired. Amongst the biggest changes made was the introduction of a successful joint workshop between the geometry course and the design...... course. This realized the full potential of structural design and firmly highlighted the creative potential in geometry for hesitant students. The joint workshop also showed potential as a general tool that can enhance curriculum integration....

  14. Directing a Quality Enhancement Plan

    Directory of Open Access Journals (Sweden)

    Ronald A. Styron, Jr.

    2015-08-01

    Full Text Available This paper is drawn from a project aimed at enhancing the quality of instructional practice and improving studentlearning outcomes in classes across an urban university located in the southern region of the United States. The strategies, employed by the project leader, are discussed in detail as framed by a new problem-solving leadership design called the Alloy Improvement Model (AIM. Data collected at the end of the second full year and reported in this paper indicated all project goals were met and that the utilization of the AIM was central to project success.

  15. The Enhanced Speed Bag System

    Science.gov (United States)

    2016-03-18

    system for helicopter resupply is a crucial development in aerial sustainment .  By Capt. Jude G.B. Coe Three enhanced speed bag systems are rigged on...NI NG & ED UC AT IO N 47 Army Sustainment July–August 2015 multipurpose cargo bag with pad- ding, one speed line assembly with a cable grip that...understand- ing of how to set up and rig the ESBS inside a Black Hawk. Validation Exercise After two joint in-progress reviews , Task Force Talon and the Iron

  16. Enhancing chaoticity of spatiotemporal chaos.

    Science.gov (United States)

    Li, Xiaowen; Zhang, Heqiao; Xue, Yu; Hu, Gang

    2005-01-01

    In some practical situations strong chaos is needed. This introduces the task of chaos control with enhancing chaoticity rather than suppressing chaoticity. In this paper a simple method of linear amplifications incorporating modulo operations is suggested to make spatiotemporal systems, which may be originally chaotic or nonchaotic, strongly chaotic. Specifically, this control can eliminate periodic windows, increase the values and the number of positive Lyapunov exponents, make the probability distributions of the output chaotic sequences more homogeneous, and reduce the correlations of chaotic outputs for different times and different space units. The applicability of the method to practical tasks, in particular to random number generators and secure communications, is briefly discussed.

  17. Gauge symmetry enhancement in Hamiltonian formalism

    CERN Document Server

    Hong, S T; Lee, T H; Oh, P; Oh, Phillial

    2003-01-01

    We study the Hamiltonian structure of the gauge symmetry enhancement in the enlarged CP(N) model coupled with U(2) chern-Simons term, which contains a free parameter governing explicit symmetry breaking and symmetry enhancement. After giving a general discussion of the geometry of constrained phase space suitable for the symmetry enhancement, we explicitly perform the Dirac analysis of out model and compute the Dirac brackets for the symmetry enhanced and broken cases. We also discuss some related issues.

  18. Resolution enhancement of color video sequences.

    Science.gov (United States)

    Shah, N R; Zakhor, A

    1999-01-01

    We propose a new multiframe algorithm to enhance the spatial resolution of frames in video sequences. Our technique specifically accounts for the possibility that motion estimation will be inaccurate and compensates for these inaccuracies. Experiments show that our multiframe enhancement algorithm yields perceptibly sharper enhanced images with significant signal-to-noise ratio (SNR) improvement over bilinear and cubic B-spline interpolation.

  19. Transcriptional enhancer from milk protein genes

    Energy Technology Data Exchange (ETDEWEB)

    Casperson, Gerald F. (Ballwin, MO); Schmidhauser, Christian T. (Berkeley, CA); Bissell, Mina J. (Berkeley, CA)

    1999-01-01

    The invention relates to novel enhancer nucleotide sequences which stimulate transcription of heterologous DNA in cells in culture. The enhancers are derived from major milk protein genes by the process of deletion mapping and functional analysis. The invention also relates to expression vectors containing the novel enhancers.

  20. Transcriptional enhancer from milk protein genes

    Energy Technology Data Exchange (ETDEWEB)

    Casperson, G.F.; Schmidhauser, C.T.; Bissell, M.J.

    1999-12-21

    The invention relates to novel enhancer nucleotide sequences which stimulate transcription of heterologous DNA in cells in culture. The enhancers are derived from major milk protein genes by the process of deletion mapping and functional analysis. The invention also relates to expression vectors containing the novel enhancers.

  1. Enhanced multifunctional paint for detection of radiation

    Energy Technology Data Exchange (ETDEWEB)

    Farmer, Joseph C.; Moses, Edward Ira; Rubenchik, Alexander M.

    2017-03-07

    An enhanced multifunctional paint apparatus, systems, and methods for detecting radiation on a surface include providing scintillation particles; providing an enhance neutron absorptive material; providing a binder; combining the scintillation particles, the enhance neutron absorptive material, and the binder creating a multifunctional paint; applying the multifunctional paint to the surface; and monitoring the surface for detecting radiation.

  2. Interpersonal leveling, independence, and self-enhancement

    DEFF Research Database (Denmark)

    Thomsen, Lotte; Sidanius, Jim; Fiske, Alan Page

    2007-01-01

    in self-enhancement. However, Danes practiced interpersonal leveling, preferring equality of outcome more than did Americans. This leveling strongly and inversely predicted self-enhancement within both cultures and mediated Danish-American differences in self-enhancement. In contrast, no independence...

  3. Threshold enhancement of diphoton resonances

    Science.gov (United States)

    Bharucha, Aoife; Djouadi, Abdelhak; Goudelis, Andreas

    2016-10-01

    We revisit a mechanism to enhance the decay width of (pseudo-)scalar resonances to photon pairs when the process is mediated by loops of charged fermions produced near threshold. Motivated by the recent LHC data, indicating the presence of an excess in the diphoton spectrum at approximately 750 GeV, we illustrate this threshold enhancement mechanism in the case of a 750 GeV pseudoscalar boson A with a two-photon decay mediated by a charged and uncolored fermion having a mass at the 1/2MA threshold and a small decay width, photons predominantly through loops of charginos with masses close to 1/2MA and ii) a two Higgs doublet model in which A is again produced by gluon fusion but decays into photons through loops of vector-like charged heavy leptons. In both these scenarios, while the mass of the charged fermion has to be adjusted to be extremely close to half of the A resonance mass, the small total widths are naturally obtained if only suppressed three-body decay channels occur. Finally, the implications of some of these scenarios for dark matter are discussed.

  4. Defense mutualisms enhance plant diversification.

    Science.gov (United States)

    Weber, Marjorie G; Agrawal, Anurag A

    2014-11-18

    The ability of plants to form mutualistic relationships with animal defenders has long been suspected to influence their evolutionary success, both by decreasing extinction risk and by increasing opportunity for speciation through an expanded realized niche. Nonetheless, the hypothesis that defense mutualisms consistently enhance plant diversification across lineages has not been well tested due to a lack of phenotypic and phylogenetic information. Using a global analysis, we show that the >100 vascular plant families in which species have evolved extrafloral nectaries (EFNs), sugar-secreting organs that recruit arthropod mutualists, have twofold higher diversification rates than families that lack species with EFNs. Zooming in on six distantly related plant clades, trait-dependent diversification models confirmed the tendency for lineages with EFNs to display increased rates of diversification. These results were consistent across methodological approaches. Inference using reversible-jump Markov chain Monte Carlo (MCMC) to model the placement and number of rate shifts revealed that high net diversification rates in EFN clades were driven by an increased number of positive rate shifts following EFN evolution compared with sister clades, suggesting that EFNs may be indirect facilitators of diversification. Our replicated analysis indicates that defense mutualisms put lineages on a path toward increased diversification rates within and between clades, and is concordant with the hypothesis that mutualistic interactions with animals can have an impact on deep macroevolutionary patterns and enhance plant diversity.

  5. Is caffeine a cognitive enhancer?

    Science.gov (United States)

    Nehlig, Astrid

    2010-01-01

    The effects of caffeine on cognition were reviewed based on the large body of literature available on the topic. Caffeine does not usually affect performance in learning and memory tasks, although caffeine may occasionally have facilitatory or inhibitory effects on memory and learning. Caffeine facilitates learning in tasks in which information is presented passively; in tasks in which material is learned intentionally, caffeine has no effect. Caffeine facilitates performance in tasks involving working memory to a limited extent, but hinders performance in tasks that heavily depend on working memory, and caffeine appears to rather improve memory performance under suboptimal alertness conditions. Most studies, however, found improvements in reaction time. The ingestion of caffeine does not seem to affect long-term memory. At low doses, caffeine improves hedonic tone and reduces anxiety, while at high doses, there is an increase in tense arousal, including anxiety, nervousness, jitteriness. The larger improvement of performance in fatigued subjects confirms that caffeine is a mild stimulant. Caffeine has also been reported to prevent cognitive decline in healthy subjects but the results of the studies are heterogeneous, some finding no age-related effect while others reported effects only in one sex and mainly in the oldest population. In conclusion, it appears that caffeine cannot be considered a ;pure' cognitive enhancer. Its indirect action on arousal, mood and concentration contributes in large part to its cognitive enhancing properties.

  6. Pharmacokinetic enhancers in HIV therapeutics.

    Science.gov (United States)

    Larson, Kajal B; Wang, Kun; Delille, Cecile; Otofokun, Igho; Acosta, Edward P

    2014-10-01

    Maximal and durable viral load suppression is one of the most important goals of HIV therapy and is directly related to adequate drug exposure. Protease inhibitors (PIs), an important component of the antiretroviral armada, were historically associated with poor oral bioavailability and high pill burden. However, because the PIs are metabolized by cytochrome P450 (CYP) 3A enzymes, intentional inhibition of these enzymes leads to higher drug exposure, lower pill burden, and therefore simplified dosing schedules with this class of drug. This is the basis of pharmacokinetic enhancement. In HIV therapy, two pharmacokinetic enhancers or boosting agents are used: ritonavir and cobicistat. Both agents inhibit CYP3A4, with cobicistat being a more specific CYP inhibitor than ritonavir. Unlike ritonavir, cobicistat does not have antiretroviral activity. Cobicistat has been evaluated in clinical trials and was recently approved in the USA as a fixed-dose combination with the integrase inhibitor, elvitegravir and two nucleos(t)ide analogs. Additional studies are examining cobicistat in fixed-dose combinations with various PIs. In this review, we summarize current knowledge of these agents and clinically relevant drug regimens and ongoing trials. Studies with elvitegravir and the novel PI TMC319011 are also discussed.

  7. Photonic crystal enhanced cytokine immunoassay.

    Science.gov (United States)

    Mathias, Patrick C; Ganesh, Nikhil; Cunningham, Brian T

    2009-01-01

    Photonic crystal surfaces are demonstrated as a means for enhancing the detection sensitivity and resolution for assays that use a fluorescent tag to quantify the concentration of an analyte protein molecule in a liquid test sample. Computer modeling of the spatial distribution of resonantly coupled electromagnetic fields on the photonic crystal surface are used to estimate the magnitude of enhancement factor compared to performing the same fluorescent assay on a plain glass surface, and the photonic crystal structure is fabricated and tested to experimentally verify the performance using a sandwich immunoassay for the protein Tumor Necrosis Factor-alpha (TNF-alpha). The demonstrated photonic crystal fabrication method utilizes a nanoreplica molding technique that allows for large-area inexpensive fabrication of the structure in a format that is compatible with confocal microarray laser scanners. The signal-to-noise ratio for fluorescent spots on the photonic crystal is increased by at least five-fold relative to the glass slide, allowing a TNF-alpha concentration of 1.6 pg/ml to be distinguished from noise on a photonic crystal surface. In addition, the minimum quantitative limit of detection on the photonic crystal surface is one-third the limit on the glass slide - a decrease from 18 pg/ml to 6 pg/ml. The increased performance of the immunoassay allows for more accurate quantitation of physiologically relevant concentrations of TNF-alpha in a protein microarray format that can be expanded to multiple cytokines.

  8. Surfactant enhanced volumetric sweep efficiency

    Energy Technology Data Exchange (ETDEWEB)

    Harwell, J.H.; Scamehorn, J.F.

    1989-10-01

    Surfactant-enhanced waterflooding is a novel EOR method aimed to improve the volumetric sweep efficiencies in reservoirs. The technique depends upon the ability to induce phase changes in surfactant solutions by mixing with surfactants of opposite charge or with salts of appropriate type. One surfactant or salt solution is injected into the reservoir. It is followed later by injection of another surfactant or salt solution. The sequence of injections is arranged so that the two solutions do not mix until they are into the permeable regions well away from the well bore. When they mix at this point, by design they form a precipitate or gel-like coacervate phase, plugging this permeable region, forcing flow through less permeable regions of the reservoir, improving sweep efficiency. The selectivity of the plugging process is demonstrated by achieving permeability reductions in the high permeable regions of Berea sandstone cores. Strategies were set to obtain a better control over the plug placement and the stability of plugs. A numerical simulator has been developed to investigate the potential increases in oil production of model systems. Furthermore, the hardness tolerance of anionic surfactant solutions is shown to be enhanced by addition of monovalent electrolyte or nonionic surfactants. 34 refs., 32 figs., 8 tabs.

  9. NANOCOMPOSITE COATINGS WITH ENHANCED HARDNESS

    Institute of Scientific and Technical Information of China (English)

    J. Musil

    2005-01-01

    The article reviews the present state of the art in the magnetron sputtering of hart and superhard nanocomposite coatings. It is shown that there are (1) two groups of hard and superhard nanocomposites: (i) nc-MN/hard phase and (ii) nc-MN/soft phase, (2) three possible origins of the enhanced hardness: (i) dislocation-dominated plastic deformation, (ii) cohesive forces between atoms and (iii) nanostructure of materials, and (3) huge differences in the microstructure of single- and two-phase films. A main attention is devoted to the formation of nanocrystalline and/or X-ray amorphous films. Such films are created in a vicinity of transitions between (i)crystalline and amorphous phases, (ii) two crystalline phases of different chemical composition or (iii) two different preferred orientations of grains of the sane material from which the coating is composed. The existence of the last transition makes it possible to explain the enhanced hardness in single-phase films. The thermal stability and oxidation resistance of hard nanocomposite films is also shortly discussed.

  10. Surfactant Enhanced Electroremediation of Phenanthrene

    Institute of Scientific and Technical Information of China (English)

    佘鹏; 杨建刚; 等

    2003-01-01

    Removal of hydrophobic organic contaminants(HOCs) form soil of low permeability by electroremediation was investigated by using phenanthrene and kaolinite as a model system.Tween 80 was added into the purging solution in order to enhance the solubility of phenanthrene.The effects of pH on the adsorption of phenanthrene and Tween 80 on kaolinite and the magnitude of ζ-potential of kaolinite were examined,respectively.The effects of electric field strength indicated by electric current on the electroremediation behavior,including the pH of purging solution,the conductivity,phenanthrene concentration and flow rate of effluent,were experimentally investigated,repectively,In case of an electric field of 25mA applied for 72 hours,over 90% of phenanthrene was removed from 424g(dry mass)of kaolinite at an energy consumption of 0.148kW.h.The experimental results described in present study show that the addition of surfactant into purging solution greatly enhances the removel of HOCs by electroremediation.

  11. RTU Comparison Calculator Enhancement Plan

    Energy Technology Data Exchange (ETDEWEB)

    Miller, James D. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Wang, Weimin [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Katipamula, Srinivas [Pacific Northwest National Lab. (PNNL), Richland, WA (United States)

    2015-07-01

    Over the past two years, Department of Energy’s Building Technologies Office (BTO) has been investigating ways to increase the operating efficiency of the packaged rooftop units (RTUs) in the field. First, by issuing a challenge to the RTU manufactures to increase the integrated energy efficiency ratio (IEER) by 60% over the existing ASHRAE 90.1-2010 standard. Second, by evaluating the performance of an advanced RTU controller that reduces the energy consumption by over 40%. BTO has previously also funded development of a RTU comparison calculator (RTUCC). RTUCC is a web-based tool that provides the user a way to compare energy and cost savings for two units with different efficiencies. However, the RTUCC currently cannot compare savings associated with either the RTU Challenge unit or the advanced RTU controls retrofit. Therefore, BTO has asked PNNL to enhance the tool so building owners can compare energy and savings associated with this new class of products. This document provides the details of the enhancements that are required to support estimating energy savings from use of RTU challenge units or advanced controls on existing RTUs.

  12. RTU Comparison Calculator Enhancement Plan

    Energy Technology Data Exchange (ETDEWEB)

    Miller, James D.; Wang, Weimin; Katipamula, Srinivas

    2014-03-31

    Over the past two years, Department of Energy’s Building Technologies Office (BTO) has been investigating ways to increase the operating efficiency of the packaged rooftop units (RTUs) in the field. First, by issuing a challenge to the RTU manufactures to increase the integrated energy efficiency ratio (IEER) by 60% over the existing ASHRAE 90.1-2010 standard. Second, by evaluating the performance of an advanced RTU controller that reduces the energy consumption by over 40%. BTO has previously also funded development of a RTU comparison calculator (RTUCC). RTUCC is a web-based tool that provides the user a way to compare energy and cost savings for two units with different efficiencies. However, the RTUCC currently cannot compare savings associated with either the RTU Challenge unit or the advanced RTU controls retrofit. Therefore, BTO has asked PNNL to enhance the tool so building owners can compare energy and savings associated with this new class of products. This document provides the details of the enhancements that are required to support estimating energy savings from use of RTU challenge units or advanced controls on existing RTUs.

  13. Enhanced Video-Oculography System

    Science.gov (United States)

    Moore, Steven T.; MacDougall, Hamish G.

    2009-01-01

    A previously developed video-oculography system has been enhanced for use in measuring vestibulo-ocular reflexes of a human subject in a centrifuge, motor vehicle, or other setting. The system as previously developed included a lightweight digital video camera mounted on goggles. The left eye was illuminated by an infrared light-emitting diode via a dichroic mirror, and the camera captured images of the left eye in infrared light. To extract eye-movement data, the digitized video images were processed by software running in a laptop computer. Eye movements were calibrated by having the subject view a target pattern, fixed with respect to the subject s head, generated by a goggle-mounted laser with a diffraction grating. The system as enhanced includes a second camera for imaging the scene from the subject s perspective, and two inertial measurement units (IMUs) for measuring linear accelerations and rates of rotation for computing head movements. One IMU is mounted on the goggles, the other on the centrifuge or vehicle frame. All eye-movement and head-motion data are time-stamped. In addition, the subject s point of regard is superimposed on each scene image to enable analysis of patterns of gaze in real time.

  14. Electrostatically enhanced core separator system

    Energy Technology Data Exchange (ETDEWEB)

    Easom, B.H.; Smolensky, L.A.; Altman, R.F. [LSR Technologies, Inc., Acton, MA (United States)

    1997-12-31

    The Electrostatically Enhanced Core Separator (EECS) system employs the same design principles as the mechanical Core Separator system plus an electrostatic separation enhancing technique. The EECS system contains a special type of separator, the EECS element, a conventional solids collector and means for flow recirculation. In the EECS system solids separation and collection are accomplished in two different components. The EECS element acts as a separator, not as a collector so particles are not collected on its walls. This eliminates or at least mitigates the problems associated with reentrainment (due to high or low dust resistivity), seepage (due to gas flow below the precipitator plates and over the hoppers), sneakage (due to gas flow both above and below the precipitator plates), and rapping reentrainment. If the EECS separation efficiency is high enough, particles cannot leave the system with the process stream. They recirculate until they are extracted by the collector. As a result, the separation efficiency of the EECS element determines the efficiency of the system, even if the collector efficiency is relatively low. 8 refs., 3 figs.

  15. Contrast-enhanced endoscopic ultrasonography

    Institute of Scientific and Technical Information of China (English)

    Nischita K Reddy; Ana Maria Ioncic(a); Adrian S(a)ftoiu; Peter Vilmann; Manoop S Bhutani

    2011-01-01

    Contrast agents are increasingly being used to characterize the vasculature in an organ of interest,to better delineate benign from malignant pathology and to aid in staging and directing therapeutic procedures.We review the mechanisms of action of first,second and third generation contrast agents and their use in various endoscopic procedures in the gastrointestinal tract.Various applications of contrast-enhanced endoscopic ultrasonography include differentiating benign from malignant mediastinal lymphadenopathy,assessment of depth of invasion of esophageal,gastric and gall bladder cancers and visualization of the portal venous system and esophageal varices.In addition,contrast agents can be used to differentiate pancreatic lesions.The use of color Doppler further increases the ability to diagnose and differentiate various pancreatic malignancies.The sensitivity of power Doppler sonography to depict tumor neovascularization can be increased by contrast agents.Contrast-enhanced harmonic imaging is a useful aid in identifying the tumor vasculature and studying pancreatic microperfusion.In the future,these techniques could potentially be used to quantify tumor perfusion,to assess and monitor the efficacy of antiangiogenic agents,to assist targeted drug delivery and allow molecular imaging.

  16. Optical antenna enhanced spontaneous emission.

    Science.gov (United States)

    Eggleston, Michael S; Messer, Kevin; Zhang, Liming; Yablonovitch, Eli; Wu, Ming C

    2015-02-10

    Atoms and molecules are too small to act as efficient antennas for their own emission wavelengths. By providing an external optical antenna, the balance can be shifted; spontaneous emission could become faster than stimulated emission, which is handicapped by practically achievable pump intensities. In our experiments, InGaAsP nanorods emitting at ∼ 200 THz optical frequency show a spontaneous emission intensity enhancement of 35 × corresponding to a spontaneous emission rate speedup ∼ 115 ×, for antenna gap spacing, d = 40 nm. Classical antenna theory predicts ∼ 2,500 × spontaneous emission speedup at d ∼ 10 nm, proportional to 1/d(2). Unfortunately, at d antenna efficiency drops below 50%, owing to optical spreading resistance, exacerbated by the anomalous skin effect (electron surface collisions). Quantum dipole oscillations in the emitter excited state produce an optical ac equivalent circuit current, I(o) = qω|x(o)|/d, feeding the antenna-enhanced spontaneous emission, where q|x(o)| is the dipole matrix element. Despite the quantum-mechanical origin of the drive current, antenna theory makes no reference to the Purcell effect nor to local density of states models. Moreover, plasmonic effects are minor at 200 THz, producing only a small shift of antenna resonance frequency.

  17. RTU Comparison Calculator Enhancement Plan

    Energy Technology Data Exchange (ETDEWEB)

    Miller, James D.; Wang, Weimin; Katipamula, Srinivas

    2014-03-31

    Over the past two years, Department of Energy’s Building Technologies Office (BTO) has been investigating ways to increase the operating efficiency of the packaged rooftop units (RTUs) in the field. First, by issuing a challenge to the RTU manufactures to increase the integrated energy efficiency ratio (IEER) by 60% over the existing ASHRAE 90.1-2010 standard. Second, by evaluating the performance of an advanced RTU controller that reduces the energy consumption by over 40%. BTO has previously also funded development of a RTU comparison calculator (RTUCC). RTUCC is a web-based tool that provides the user a way to compare energy and cost savings for two units with different efficiencies. However, the RTUCC currently cannot compare savings associated with either the RTU Challenge unit or the advanced RTU controls retrofit. Therefore, BTO has asked PNNL to enhance the tool so building owners can compare energy and savings associated with this new class of products. This document provides the details of the enhancements that are required to support estimating energy savings from use of RTU challenge units or advanced controls on existing RTUs.

  18. Fingerprint Image Enhancement By Develop Mehtre Technique

    Directory of Open Access Journals (Sweden)

    Mustafa Salah Khalefa

    2011-12-01

    Full Text Available Fingerprint identification is one of the most reliable biometrics technologies. There are manyapplications of fingerprint recognition such as voting, ecommerce, bank, virtual banks and military.Fingerprint image enhancement is an essential preprocessing step in extract minutiae from the inputfingerprint images. In this paper, we propose an image enhancement method by developing Mehtermethod for directional image. The enhancement is done by added the Block Filtering, HistogramEqualization and High-Pass Filtering. We have evaluated the performance of the enhancement imagemethod by tested it with 100 fingerprint images. Experimental results show the enhancement methodimproves the recognition more accuracy.

  19. Enhancing the US Power Infrastructure

    Energy Technology Data Exchange (ETDEWEB)

    Charles Alexander

    2010-05-31

    The primary motivation for this set of research activities was to develop a foundation in several aspects of power in order to position Cleveland State University to lead a multiuniversity effort to secure funding for enhanced power system projects and to be able to eventually secure a NASA Space Power Systems Center status through the competitive bidding process. This was accomplished by focusing on these major project areas, (1) the design of the next generation nuclear-electric power generation system, (2) the design of a distributed, fault-tolerant, and modular power system, and (3) the development of the dynamics and control of active magnetic bearings for flywheel energy storage without using conventional sensors.

  20. Enhancing AFLOW Visualization using Jmol

    Science.gov (United States)

    Lanasa, Jacob; New, Elizabeth; Stefek, Patrik; Honaker, Brigette; Hanson, Robert; Aflow Collaboration

    The AFLOW library is a database of theoretical solid-state structures and calculated properties created using high-throughput ab initio calculations. Jmol is a Java-based program capable of visualizing and analyzing complex molecular structures and energy landscapes. In collaboration with the AFLOW consortium, our goal is the enhancement of the AFLOWLIB database through the extension of Jmol's capabilities in the area of materials science. Modifications made to Jmol include the ability to read and visualize AFLOW binary alloy data files, the ability to extract from these files information using Jmol scripting macros that can be utilized in the creation of interactive web-based convex hull graphs, the capability to identify and classify local atomic environments by symmetry, and the ability to search one or more related crystal structures for atomic environments using a novel extension of inorganic polyhedron-based SMILES strings

  1. Enhanced Li-Ion Battery

    Directory of Open Access Journals (Sweden)

    Natasha Ross

    2015-01-01

    Full Text Available Au with Pd nanoparticles were synthesized and coated onto the spinel LiMn2O4 via a coprecipitation calcination method with the objective to improve the microstructure, conductivity, and electrochemical activities of pristine LiMn2O4. The novel LiPdAuxMn2-xO4 composite cathode had high phase purity, well crystallized particles, and more regular morphological structures with narrow size distributions. At enlarged cycling potential ranges the LiPdAuxMn2-xO4 sample delivered 90 mAh g−1 discharge capacity compared to LiMn2O4 (45 mAh g−1. It was concluded that even a small amount of the Pd and Au enhanced both the lithium diffusivity and electrochemical conductivity of the host sample due to the beneficial properties of their synergy.

  2. Enhancing the US Power Infrastructure

    Energy Technology Data Exchange (ETDEWEB)

    Charles Alexander

    2010-05-31

    The primary motivation for this set of research activities was to develop a foundation in several aspects of power in order to position Cleveland State University to lead a multiuniversity effort to secure funding for enhanced power system projects and to be able to eventually secure a NASA Space Power Systems Center status through the competitive bidding process. This was accomplished by focusing on these major project areas, (1) the design of the next generation nuclear-electric power generation system, (2) the design of a distributed, fault-tolerant, and modular power system, and (3) the development of the dynamics and control of active magnetic bearings for flywheel energy storage without using conventional sensors.

  3. Enhanced NIF neutron activation diagnostics.

    Science.gov (United States)

    Yeamans, C B; Bleuel, D L; Bernstein, L A

    2012-10-01

    The NIF neutron activation diagnostic suite relies on removable activation samples, leading to operational inefficiencies and a fundamental lower limit on the half-life of the activated product that can be observed. A neutron diagnostic system measuring activation of permanently installed samples could remove these limitations and significantly enhance overall neutron diagnostic capabilities. The physics and engineering aspects of two proposed systems are considered: one measuring the (89)Zr/(89 m)Zr isomer ratio in the existing Zr activation medium and the other using potassium zirconate as the activation medium. Both proposed systems could improve the signal-to-noise ratio of the current system by at least a factor of 5 and would allow independent measurement of fusion core velocity and fuel areal density.

  4. Photosynthesis solutions to enhance productivity.

    Science.gov (United States)

    Foyer, Christine H; Ruban, Alexander V; Nixon, Peter J

    2017-09-26

    The concept that photosynthesis is a highly inefficient process in terms of conversion of light energy into biomass is embedded in the literature. It is only in the past decade that the processes limiting photosynthetic efficiency have been understood to an extent that allows a step change in our ability to manipulate light energy assimilation into carbon gain. We can therefore envisage that future increases in the grain yield potential of our major crops may depend largely on increasing the efficiency of photosynthesis. The papers in this issue provide new insights into the nature of current limitations on photosynthesis and identify new targets that can be used for crop improvement, together with information on the impacts of a changing environment on the productivity of photosynthesis on land and in our oceans.This article is part of the themed issue 'Enhancing photosynthesis in crop plants: targets for improvement'. © 2017 The Author(s).

  5. Static magnetic fields enhance turbulence

    CERN Document Server

    Pothérat, Alban

    2015-01-01

    More often than not, turbulence occurs under the influence of external fields, mostly rotation and magnetic fields generated either by planets, stellar objects or by an industrial environment. Their effect on the anisotropy and the dissipative behaviour of turbulence is recognised but complex, and it is still difficult to even tell whether they enhance or dampen turbulence. For example, externally imposed magnetic fields suppress free turbulence in electrically conducting fluids (Moffatt 1967), and make it two-dimensional (2D) (Sommeria & Moreau 1982); but their effect on the intensity of forced turbulence, as in pipes, convective flows or otherwise, is not clear. We shall prove that since two-dimensionalisation preferentially affects larger scales, these undergo much less dissipation and sustain intense turbulent fluctuations. When higher magnetic fields are imposed, quasi-2D structures retain more kinetic energy, so that rather than suppressing forced turbulence, external magnetic fields indirectly enha...

  6. Enhanced performance hybrid-arq

    KAUST Repository

    Fareed, Muhammad Mehboob

    2016-06-16

    Apparatuses, computer readable media, and methods are provided for enhancing hybrid automatic repeat request (ARQ) performance. In an example method, a communication device transmits a first element of a vector, where the vector is selected using the information bits to be transmitted as an index in a code book. In some embodiments, this code book is constructed using Linear Constellation Precoding (LCP). If a NACK is received, the communication device transmits a second element of the vector. The process of transmitting elements of the vector continues until an ACK is received or the maximum number of transmission attempts is reached. If an ACK is received, the communication device transmits a first element of another vector of the code book that encodes a second set of information bits. This procedure may continue until all information bits have been transmitted successfully.

  7. Enhanced collectivity in 74Ni

    CERN Document Server

    Aoi, N; Takeuchi, S; Suzuki, H; Bazin, D; Bowen, M D; Campbell, C M; Cook, J M; Dinca, D -C; Gade, A; Glasmacher, T; Iwasaki, H; Kubo, T; Kurita, K; Motobayashi, T; Mueller, W F; Nakamura, T; Sakurai, H; Takashina, M; Terry, J R; Yoneda, K; Zwahlen, H

    2010-01-01

    The neutron-rich nucleus 74Ni was studied with inverse-kinematics inelastic proton scattering using a 74Ni radioactive beam incident on a liquid hydrogen targetat a center-of-mass energy of 80 MeV. From the measured de-excitation gamma-rays, the population of the first 2+ state was quantified. The angle-integrated excitation cross section was determined to be 14(4) mb. A deformation length of delta = 1.04(16) fm was extracted in comparison with distorted wave theory, which suggests that the enhancement of collectivity established for 70Ni continues up to 74Ni. A comparison with results of shell model and quasi-particle random phase approximation calculations indicates that the magic character of Z = 28 or N = 50 is weakened in 74Ni.

  8. Enhanced collectivity in 74Ni

    Science.gov (United States)

    Aoi, N.; Kanno, S.; Takeuchi, S.; Suzuki, H.; Bazin, D.; Bowen, M. D.; Campbell, C. M.; Cook, J. M.; Dinca, D.-C.; Gade, A.; Glasmacher, T.; Iwasaki, H.; Kubo, T.; Kurita, K.; Motobayashi, T.; Mueller, W. F.; Nakamura, T.; Sakurai, H.; Takashina, M.; Terry, J. R.; Yoneda, K.; Zwahlen, H.

    2010-09-01

    The neutron-rich nucleus 74Ni was studied with inverse-kinematics inelastic proton scattering using a 74Ni radioactive beam incident on a liquid hydrogen target at a center-of-mass energy of 80 MeV. From the measured de-excitation γ rays, the population of the first 2+ state was quantified. The angle-integrated excitation cross section was determined to be 14(4) mb. A deformation length of δ=1.04(16) fm was extracted in comparison with distorted wave theory, which suggests that the enhancement of collectivity established for 70Ni continues up to 74Ni. A comparison with results of shell model and quasi-particle random phase approximation calculations indicates that the magic character of Z=28 or N=50 is weakened in 74Ni.

  9. Q-enhanced racetrack microresonators

    Science.gov (United States)

    Chamorro-Posada, P.

    2017-03-01

    A Q-enhancement strategy for racetrack microresonators is put forward. The design is based on the modification of the resonator geometry in order to mitigate the two main sources of radiation loss in the presence of curved waveguides: the discontinuities at the junctions between straight waveguides and the bent sections, and the continuous loss at the curved waveguide sectors. At the same time, the modifications of the geometry do not affect the versatility of coupling of racetrack resonators in integrated optical circuits, which is their main advantage over ring microresonators. The proposal is applied to the design of high-Q racetrack resonators for the silicon nitride CMOS-compatible platform having bent radii amenable for large-scale photonic integration. Numerical calculations show over 100% improvement of the Q factor in Si3N4/SiO2 resonators.

  10. Enhancing undergraduate students’ communications skills

    DEFF Research Database (Denmark)

    Jørgensen, Merete; Witt, Klaus; Fridorff-Jens, Peter Kindt

    2014-01-01

    19729 Abstract Title: Enhancing undergraduate students communications skills Abstract Authors: •Merete Jorgensen, Copenhagen University , Family Medicine , Copenhagen •Klaus Witt, Research Unit , Family Medicine , Copenhagen •Peter Kindt Fridorff-Jens, Copenhagen University , IT-unit , Copenhagen...... the Consultation Logic (CL) and Consultation Analysis (CA), based on the Patient-Centred Consultation. To investigate the effect of various teaching methods in communication skills we have developed a scientific tool (DanSCORE) based on CL and CA to measure the students analysing ability Summary of work It has...... and they alternate with five plus four hour’s sessions of assessing, analyzing and discussion the videos in small groups with a peer (university teacher) and fellow students.We focus in our project on communication skills. 600 medical students are enrolled in the project. Changes in analyzing ability...

  11. Quantum-enhanced absorption refrigerators

    CERN Document Server

    Correa, Luis A; Alonso, Daniel; Adesso, Gerardo

    2014-01-01

    Thermodynamics is a branch of science blessed by an unparalleled combination of generality of scope and formal simplicity. Based on few natural assumptions together with the four laws, it sets the boundaries between possible and impossible in macroscopic aggregates of matter. This triggered groundbreaking achievements in physics, chemistry and engineering over the last two centuries. Close analogues of those fundamental laws are now being established at the level of individual quantum systems, thus placing limits on the operation of quantum-mechanical devices. Here we study quantum absorption refrigerators, which are driven by heat rather than external work. We establish thermodynamic performance bounds for these machines and investigate their quantum origin. We also show how those bounds may be pushed beyond what is classically achievable, by suitably tailoring the environmental fluctuations via quantum reservoir engineering techniques. Such superefficient quantum-enhanced cooling realises a promising step t...

  12. Shale Oil Value Enhancement Research

    Energy Technology Data Exchange (ETDEWEB)

    James W. Bunger

    2006-11-30

    Raw kerogen oil is rich in heteroatom-containing compounds. Heteroatoms, N, S & O, are undesirable as components of a refinery feedstock, but are the basis for product value in agrochemicals, pharmaceuticals, surfactants, solvents, polymers, and a host of industrial materials. An economically viable, technologically feasible process scheme was developed in this research that promises to enhance the economics of oil shale development, both in the US and elsewhere in the world, in particular Estonia. Products will compete in existing markets for products now manufactured by costly synthesis routes. A premium petroleum refinery feedstock is also produced. The technology is now ready for pilot plant engineering studies and is likely to play an important role in developing a US oil shale industry.

  13. The Game Enhanced Learning Model

    DEFF Research Database (Denmark)

    Reng, Lars; Schoenau-Fog, Henrik

    2016-01-01

    In this paper, we will introduce the Game Enhanced learning Model (GEM), which describes a range of gameoriented learning activities. The model is intended to give an overview of the possibilities of game-based learning in general and all the way up to purposive game productions. In the paper, we...... will describe the levels of the model, which is based on our experience in teaching professional game development at university level. Furthermore, we have been using the model to inspire numerous educators to improve their students’ motivation and skills. The model presents various game-based learning...... activities, and depicts their required planning and expected outcome through eight levels. At its lower levels, the model contains the possibilities of using stand-alone analogue and digital games as teachers, utilizing games as a facilitator of learning activities, exploiting gamification and motivating...

  14. Enhanced colloidal stability of hydroxyapatite

    Science.gov (United States)

    Borum, La Rhonda Terese

    Hydroxyapatite, Ca10(PO4)6(OH) 2 is the most thermodynamically stable calcium phosphate in physiological environments. Hence, it is the main inorganic mineral found in bone and teeth. Its colloidal stability, however, is poor because hydroxyapatite (HAp) particles exhibit sediment formation upon standing at short time periods, where agglomerates form and lead to non-homogeneous suspensions. Surface modification is a promising method to tailor the colloidal stability of hydroxyapatite for biomaterial applications. Three techniques to modify the HAp surface and enhance the colloidal stability of HAp were investigated. Modified particles were characterized by methods sensitive to surface chemistry changes, such as sedimentation studies, diffuse reflectance Fourier transform infrared spectroscopy (DRIFT), Brunauer-Emmett-Teller (BET) surface area, and electrophoresis. Sedimentation studies demonstrated how effective each technique was in improving the colloidal stability of hydroxyapatite particles. Electrophoresis provided information on electrostatic interactions within each system. The first technique entailed an esterification reaction of the HAp surface with dodecyl alcohol at elevated temperatures. DRIFT results showed that dodecyl groups from the alcohol replaced acidic hydroxyl and phosphate sites on the HAp surface, giving rise to enhanced colloidal stability through steric interactions in ethanol suspensions. TGA curves gave insight to the degree of esterification for the esterified particles. Higher reaction temperatures give rise to a higher degree of esterification resulting in better colloidal stability. The second technique applied a silica coating on the HAp surface by the hydrolysis of tetraethyl orthosilicate in ethanol. Silica was coated onto the HAp surface at 5--75 wt% loading amounts. A combination of acid dissolution and x-ray diffraction (XRD), along with BET showed that the silica coating is complete at 50 wt% silica loading. The silica coating

  15. A Thomistic appraisal of human enhancement technologies.

    Science.gov (United States)

    Eberl, Jason T

    2014-08-01

    Debate concerning human enhancement often revolves around the question of whether there is a common "nature" that all human beings share and which is unwarrantedly violated by enhancing one's capabilities beyond the "species-typical" norm. I explicate Thomas Aquinas's influential theory of human nature, noting certain key traits commonly shared among human beings that define each as a "person" who possesses inviolable moral status. Understanding the specific qualities that define the nature of human persons, which includes self-conscious awareness, capacity for intellective thought, and volitional autonomy, informs the ethical assessment of various forms of enhancement. Some forms of cognitive and physical enhancement may be desirable from the perspective of what constitutes the "flourishing" of human persons in our fundamental nature; while other forms of enhancement, such as emotive or so-called "moral" enhancement, run the risk of detracting from human flourishing when evaluated from the virtue-theoretic perspective Aquinas promotes.

  16. Cognitive enhancement. Effort of definition, and methods

    Directory of Open Access Journals (Sweden)

    Artur Gunia

    2015-12-01

    Full Text Available The idea of cognitive enhancement refers to multifaceted and interdisciplinary approach aimed at improving human mental processes. Cognitive enhancement is the amplification or extension of core mind capacities through improvement or augmentation of either internal or external information processing systems. This includes improvements of intelligence and attention, reinforcement of creativity and memory, or extension of perception range. The main feature of cognitive enhancement is voluntariness of use for overcoming natural mental limitations. This article is a synthesis of current trends in cognitive enhancement from the perspective of transhumanism. The article presents various definitions of cognitive enhancement, methods of cognitive enhancement (biotechnological methods, non-pharmacological methods, IT methods as well as challenges and questions concerning improving human mental processes.

  17. Plant Enhancers: A Call for Discovery.

    Science.gov (United States)

    Weber, Blaise; Zicola, Johan; Oka, Rurika; Stam, Maike

    2016-11-01

    Higher eukaryotes typically contain many different cell types, displaying different cellular functions that are influenced by biotic and abiotic cues. The different functions are characterized by specific gene expression patterns mediated by regulatory sequences such as transcriptional enhancers. Recent genome-wide approaches have identified thousands of enhancers in animals, reviving interest in enhancers in gene regulation. Although the regulatory roles of plant enhancers are as crucial as those in animals, genome-wide approaches have only very recently been applied to plants. Here we review characteristics of enhancers at the DNA and chromatin level in plants and other species, their similarities and differences, and techniques widely used for genome-wide discovery of enhancers in animal systems that can be implemented in plants. Copyright © 2016 Elsevier Ltd. All rights reserved.

  18. Interactive Image Enhancement by Fuzzy Relaxation

    Institute of Scientific and Technical Information of China (English)

    Shang-Ming Zhou; John Q.Can; Li-Da Xu; Robert John

    2007-01-01

    In this paper, an interactive image enhancement (HE) technique based on fuzzy relaxation is presented, which allows the user to select different intensity levels for enhancement and intermit the enhancement process according to his/her preference in applications. First, based on an analysis of the convergence of a fuzzy relaxation algorithm for image contrast enhancement, an improved version of this algorithm, which is called FuzzIIE Method 1, is suggested by deriving a relationship between the convergence regions and the parameters in the transformations defined in the algorithm. Then a method called FuzzIIE Method 2 is introduced by using a different fuzzy relaxation function, in which there is no need to re-select the parameter values for interactive image enhancement. Experimental results are presented demonstrating the enhancement capabilities of the proposed methods under different conditions.

  19. Comparative enhancing effects of electret with chemical enhancers on transdermal delivery of meloxicam in vitro

    Energy Technology Data Exchange (ETDEWEB)

    Cui, L L; Hou, X M; Li, G D [Department of Inorganic Chemistry, College of Pharmacy, Second Military Medical University, Shanghai, 200433 (China); Jiang, J; Liang, Y Y; Xin, X [Department of Physics and Mathematics, College of Basic Medical Sciences, Second Military Medical University, Shanghai, 200433 (China)], E-mail: cuilili39@hotmail.com, E-mail: JJiang0827@hotmail.com

    2008-12-01

    Electret offers enhancing effect in transdermal drug delivery for altering of the arrangement of lipid molecules in the stratum corneum, forming many transient permeable apertures and enhancing the transdermal drug delivery. In this paper, meloxicam patch formulations were developed to make the comparative study of transdermal drug delivery between electret and chemical enhancers. Patches were made into control, electret, chemical enhancer and electret with chemical enhancer ones, according to the preparation procedure. The electret combined with chemical enhancer patch was designed to probe the incorporation between electret and chemical enhancer in transdermal drug delivery. The meloxicam release from the patch was found to increase in order of blank, chemical enhancer, electret and electret with chemical enhancer patch, in general.

  20. Enhancement patterns and pseudo-washout of hepatic haemangiomas on gadoxetate disodium-enhanced liver MRI

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Bohyun [University of Ulsan College of Medicine, Asan Medical Center, Department of Radiology and Research Institute of Radiology, Seoul (Korea, Republic of); Ajou University School of Medicine, Department of Radiology, Suwon (Korea, Republic of); Byun, Jae Ho; Kim, Hyoung Jung; Won, Hyung Jin; Kim, So Yeon; Shin, Yong Moon; Kim, Pyo Nyun [University of Ulsan College of Medicine, Asan Medical Center, Department of Radiology and Research Institute of Radiology, Seoul (Korea, Republic of)

    2016-01-15

    To compare the enhancement patterns and prevalence of pseudo-washout between rapidly and slowly enhancing hepatic haemangiomas on gadoxetate disodium-enhanced MRI in patients with chronic liver disease (CLD) and healthy liver (HL). On gadoxetate disodium-enhanced MRI, the extent of intralesional arterial enhancement >50 % and ≤50 % of lesions was defined as rapid and slow enhancement, respectively. The enhancement patterns and presence of pseudo-washout during the portal venous phase (PVP) and transitional phase (TP) of 74 hepatic haemangiomas were retrospectively evaluated in the CLD and HL groups. Sequential changes of signal-to-noise ratio (SNR) were measured in unenhanced phase, PVP and TP. Irrespective of hepatic health status, pseudo-washout in TP was significantly more common in the rapidly enhancing haemangiomas (p ≤ 0.026). In both groups, rapidly enhancing haemangiomas showed complete or progressive incomplete enhancement in PVP, which either lasted or transformed to pseudo-washout in TP, whereas slowly enhancing haemangiomas showed progressive incomplete enhancement in PVP and TP. SNR of hepatic parenchyma continued to rise until TP, whereas that of portal vein and haemangioma falls in TP. Regardless of CLD, pseudo-washout in TP was more common in rapidly than in slowly enhancing haemangiomas, with enhancement patterns differing in the two subgroups. (orig.)

  1. BIR 2014 - Bibliometric-enhanced Information Retrieval

    DEFF Research Database (Denmark)

    This first “Bibliometric-enhanced Information Retrieval” (BIR 2014) workshop1 aims to engage with the IR community about possible links to bibliometrics and scholarly communication. Bibliometric techniques are not yet widely used to enhance retrieval processes in digital libraries, although...... for the incorporation of bibliometric-enhanced services into retrieval at the digital library interface. Our interests include information retrieval, information seeking, science modelling, network analysis, and digital libraries. The goal is to apply insights from bibliometrics, scientometrics, and informetrics...

  2. Enhancement of colposcopic image by sulphosalicylic acid.

    Directory of Open Access Journals (Sweden)

    Khilnani P

    1993-01-01

    Full Text Available Acetic acid is used conventionally for enhancement of the colposcopic image. We used sulphosalicylic acid instead of acetic acid in 50 normal cases. The normal appearance was enhanced in all cases. The image was also enhanced in 70% cases of cervical intraepithelial neoplasia and 90% cases of cervical condyloma accuminata. The image was not inferior to that with acetic acid in any of the cases.

  3. Adopting Emerging Technology to Enhance Organizational Performance

    Science.gov (United States)

    2009-06-01

    Center, Pacific with open-source, competitive intelligence to enhance their situational awareness and fulfill the external information needs of the...Group – An Overview To provide and enhance the situational awareness of its parent organization, the CSG has employed a competitive intelligence infrastructure...in 2001 by senior leadership to address SA imperative • Why: Provide open-source competitive intelligence to enhance situational awareness of SSC

  4. Surface-enhanced Raman spectroscopy: nonlocal limitations

    DEFF Research Database (Denmark)

    Toscano, Giuseppe; Raza, S.; Xiao, Sanshui;

    2012-01-01

    Giant field enhancement and field singularities are a natural consequence of the commonly employed local-response framework. We show that a more general nonlocal treatment of the plasmonic response leads to new and possibly fundamental limitations on field enhancement with important consequences ...... by periodic arrays of half-cylinders (up to 120 nm in radius), we find no enhancement factors exceeding 10 orders of magnitude (10(10)). (C) 2012 Optical Society of America...

  5. Enhancements in entrepreneurial services : JAMK Generator

    OpenAIRE

    Schepers, Stefan

    2014-01-01

    The JAMK Generator assigned this task of enhancing the services of the Generator with the objective to increase the value of the Generator for the students through developing new enhancements. The enhancement is based on five concepts, which were researched in detail among the students of JAMK through a survey. In general, students are interested in entrepreneurship itself during their studies or in anticipation of their future careers. Students have been curious about an entrepreneurial ...

  6. Labor potential: enhancing its development

    Directory of Open Access Journals (Sweden)

    O.P. Melnichuk

    2016-06-01

    Full Text Available This publication presents the views of the author about the need to expand research of labor potential, estimation of quantitative indicators and qualitative characteristics at the individual, regional levels and the state as a whole to develop the mechanisms of its development. The existing methods of labour potential assessment are mainly based on the probable approach taking into account external and internal factors. In the case of assessment of labour potential of a single enterprise for the most suitable for this production method the mechanisms of its development can be worked out. However, for the state under a certain depreciation of the resource, property, financial and other potentials, aggressive manifestations of the crisis phenomena, processes etc. to resolve urgent is the problem of enhancing the development of qualitative characteristics of labor potential at all its levels. In this context it is important to exploit the potential of domestic education and science which now continue to be reformed for the sake of achieving European standards, using the advanced experience of other countries. Every means of legal, financial, managerial, and organizational impact should be used for this.

  7. Carbon-enhanced VRLA batteries.

    Energy Technology Data Exchange (ETDEWEB)

    Enos, David George; Hund, Thomas D.; Shane, Rod (East Penn Manufacturing, Lyon Station, PA)

    2010-10-01

    The addition of certain forms of carbon to the negative plate in valve regulated lead acid (VRLA) batteries has been demonstrated to increase the cycle life of such batteries by an order of magnitude or more under high-rate, partial-state-of-charge operation. Such performance will provide a significant impact, and in some cases it will be an enabling feature for applications including hybrid electric vehicles, utility ancillary regulation services, wind farm energy smoothing, and solar photovoltaic energy smoothing. There is a critical need to understnd how the carbon interacts with the negative plate and achieves the aforementioned benefits at a fundamental level. Such an understanding will not only enable the performance of such batteries to be optimzied, but also to explore the feasibility of applying this technology to other battery chemistries. In partnership with the East Penn Manufacturing, Sandia will investigate the electrochemical function of the carbon and possibly identify improvements to its anti-sulfation properties. Shiomi, et al. (1997) discovered that the addition of carbon to the negative active material (NAM) substantially reduced PbSO{sub 4} accumulation in high rate, partial state of charge (HRPSoC) cycling applications. This improved performance with a minimal cost. Cycling applications that were uneconomical for traditional VRLA batteries are viable for the carbon enhanced VRLA. The overall goal of this work is to quantitatively define the role that carbon plays in the electrochemistry of a VRLA battery.

  8. Enhanced potentiometry by metallic nanoparticles.

    Science.gov (United States)

    Noyhouzer, T; Valdinger, I; Mandler, D

    2013-09-03

    Measuring the oxidation-reduction potential (Eh) requires an interface that is not selective toward specific species but exchanges electrons with all redox couples in the solution. Sluggish electron transfer (ET) kinetics with the species will not reflect the "true" Eh of the solution. Here, we present a novel approach by which adsorbed metal nanoparticles (NPs) are used for enhancing ET exchange rates between redox species and electrode surface and therefore affect significantly the measurement of the open circuit potential (OCP) and cyclic voltammetry (CV). The OCP and CV of various organic and inorganic species such as l-dopa, dopac, iron(II), and iodide are measured by bare stainless steel and by stainless steel modified by either Pt or Au NPs. We study the effect of the surface coverage of the stainless steel surface by NPs on the electrochemical response. Moreover, the stainless steel electrode was modified simultaneously by Au and Pt nanoparticles. This improved concurrently the stainless steel response (CV and potentiometry) toward two different species; l-dopa, which shows fast electron transfer on Pt, and catechol, which exhibits fast electron transfer on Au. We believe that this approach could be a first step toward developing a superior electrode for measuring the "true" Eh of complex aquatic systems.

  9. Enhanced Model for Fast Ignition

    Energy Technology Data Exchange (ETDEWEB)

    Mason, Rodney J. [Research Applications Corporation, Los Alamos, NM (United States)

    2010-10-12

    Laser Fusion is a prime candidate for alternate energy production, capable of serving a major portion of the nation's energy needs, once fusion fuel can be readily ignited. Fast Ignition may well speed achievement of this goal, by reducing net demands on laser pulse energy and timing precision. However, Fast Ignition has presented a major challenge to modeling. This project has enhanced the computer code ePLAS for the simulation of the many specialized phenomena, which arise with Fast Ignition. The improved code has helped researchers to understand better the consequences of laser absorption, energy transport, and laser target hydrodynamics. ePLAS uses efficient implicit methods to acquire solutions for the electromagnetic fields that govern the accelerations of electrons and ions in targets. In many cases, the code implements fluid modeling for these components. These combined features, "implicitness and fluid modeling," can greatly facilitate calculations, permitting the rapid scoping and evaluation of experiments. ePLAS can be used on PCs, Macs and Linux machines, providing researchers and students with rapid results. This project has improved the treatment of electromagnetics, hydrodynamics, and atomic physics in the code. It has simplified output graphics, and provided new input that avoids the need for source code access by users. The improved code can now aid university, business and national laboratory users in pursuit of an early path to success with Fast Ignition.

  10. Does facial resemblance enhance cooperation?

    Directory of Open Access Journals (Sweden)

    Trang Giang

    Full Text Available Facial self-resemblance has been proposed to serve as a kinship cue that facilitates cooperation between kin. In the present study, facial resemblance was manipulated by morphing stimulus faces with the participants' own faces or control faces (resulting in self-resemblant or other-resemblant composite faces. A norming study showed that the perceived degree of kinship was higher for the participants and the self-resemblant composite faces than for actual first-degree relatives. Effects of facial self-resemblance on trust and cooperation were tested in a paradigm that has proven to be sensitive to facial trustworthiness, facial likability, and facial expression. First, participants played a cooperation game in which the composite faces were shown. Then, likability ratings were assessed. In a source memory test, participants were required to identify old and new faces, and were asked to remember whether the faces belonged to cooperators or cheaters in the cooperation game. Old-new recognition was enhanced for self-resemblant faces in comparison to other-resemblant faces. However, facial self-resemblance had no effects on the degree of cooperation in the cooperation game, on the emotional evaluation of the faces as reflected in the likability judgments, and on the expectation that a face belonged to a cooperator rather than to a cheater. Therefore, the present results are clearly inconsistent with the assumption of an evolved kin recognition module built into the human face recognition system.

  11. QUALITY ENHANCEMENT IN MEDICAL EDUCATION

    Directory of Open Access Journals (Sweden)

    Mostafa Nejati Ajibisheh

    2007-10-01

    Full Text Available Since ancient time, education has been evaluated in terms of its practical value among the Chinese; however, despite its long history, performance evaluation is the most complex and controversial of human resource management techniques (Roberts, 2003, and a little understood function of organizational life.Performance appraisal in both the private and the public sectors have become an integral part of work life. Of course, there is a growing interest to use performance management techniques in educational institutes in order to increase the competitiveness and quality of university education in a globalized environment .Accordingly, medical education requires special performance management and excellence models to improve the quality of course materials and provided services.The aim of this article is to develop a model of academic excellence based on a combination of SERVQUAL technique, Balanced Scorecard model, and EFQM Excellence Model. The SERVQUAL technique can be used to identify the gap between medical students\\' expectations and perceived experience as indicators of service quality, to measure quality of services offered by medical universities.In this article, with the use of Balanced Scorecard and EFQM, a comprehensive model will be introduced to enhance the quality of medical education. The model will recommend a process within different academic quality dimensions. In addition, the paper will introduce approaches to use available resources effectively to improve educational development.

  12. How harmless is FFA enhancement?

    Science.gov (United States)

    Tesserommatis, C; Tsopanakis, C; Symeonoglou, G; Loukissa, M; Kouvarou, E; Varonos, D D

    1996-01-01

    Standard heparin as well as low molecular weight heparin (LMWH) increase lipid levels in serum. It has been reported that a diet rich in long chain saturated fatty acids can enhance the susceptibility to experimental thrombosis. The mechanism by which serum fatty acids may provoke thrombosis is not clear. It is possible that the fatty acids change the properties of the cell membrane and thereby modify the response of platelets to aggregating agents. Heparin and its LMW fractions, by mobilising lipoprotein lipase that hydrolyses serum triglycerides (TG), cause the serum TG to increase, a well known "clearing effect' of heparin in turbid lipemic plasma. This effect may have no significance when it lasts for a short time; however, a long-lasting heparin effect on TG serum levels may have important consequences. The purpose of this study was to examine the time span of the action of heparin and its fractions and to investigate variations in the concentration of digoxin, which is a compound with narrow therapeutic width. The investigated substances after 2 days administration, provoked serum concentration increases of free fatty acids (FFA), TG and HDL-C. Seven days after stopping drug administration, FFA and HDL-C levels remained high, while triglycerides declined. Serum total cholesterol remained unchanged throughout. Digoxin levels increased non-significantly after heparin administration and during swimming stress, while a lipid diet caused a serum digoxin concentration increase.

  13. Facebook enhances antidepressant pharmacotherapy effects.

    Science.gov (United States)

    Mota Pereira, Jorge

    2014-01-01

    Treatment-resistant major depressive disorder (TR-MDD) is a complex condition, with very low remission rates. In recent years some studies have been conducted on the implementation of cognitive behavioral therapy and psychodynamic psychotherapy interventions via the Internet to MDD patients, and results have been promising. However, there have been no studies in patients with TR-MDD nor with the use of Facebook with the psychiatrist as "friend." 60 TR-MDD patients were randomized to one of three groups: Facebook group with psychiatrist as "friend," Facebook group without psychiatrist as "friend," and control group (no Facebook use). Both Facebook groups spent at least 1 hour/day on Facebook, 7 days/week, during the 3 months. All patients maintained their usual pharmacotherapy. All participants were evaluated at baseline and at 1, 2, and 3 months for depressive symptoms using HAD17 and BDI-II. Results show that both Facebook groups had a decrease on HADM17 and BDI-II scores as well as higher remission and response rates than the control group, with better results if the psychiatrist was a "friend" on Facebook. Therefore, in TR-MDD, Facebook can be used as an effective enhancement therapy, adjuvant to pharmacological therapy with regular consultations, especially if the psychiatrist is the patient's online "friend."

  14. Noise-enhanced gel electrophoresis.

    Science.gov (United States)

    Shi, Nan; Ugaz, Victor M

    2014-07-01

    Macromolecules confined within a nanoporous matrix experience entropic trapping when their dimensions approach the average pore size, leading to emergence of anomalous transport behavior that can be beneficial in separation applications. But the ability to exploit these effects in practical settings (e.g., electrophoretic separation of DNA) has been hindered by additional dispersion introduced as a consequence of the uncorrelated process by which the embedded macromolecules discretely hop from pore to pore. Here, we show how both the source and solution to these difficulties are intimately linked to the inherent dynamics of the underlying activated transport mechanism. By modulating the applied electric field at a frequency tuned to the characteristic activation timescale, a resonance condition can be established that synergistically combines accelerated mobility and reduced diffusion. This resonance effect can be precisely manipulated by adjusting the magnitude and period of the driving electric field, enabling enhanced separation performance and bi-directional transport of different-sized species to be achieved. Notably, these phenomena are readily accessible in ordinary hydrogels (as opposed to idealized nanomachined topologies) suggesting broad potential to apply them in a host of useful settings. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  15. Enhancing colposcopy with polarized light.

    Science.gov (United States)

    Ferris, Daron G; Li, Wenjing; Gustafsson, Ulf; Lieberman, Richard W; Galdos, Oscar; Santos, Carlos

    2010-07-01

    To determine the potential utility of polarized light used during colposcopic examinations. Matched, polarized, and unpolarized colposcopic images and diagnostic annotations from 31 subjects receiving excisional treatment of cervical neoplasia were compared. Sensitivity, specificity, and mean Euclidean distances between the centroids of the gaussian ellipsoids for the different epithelial types were calculated for unpolarized and polarized images. The sensitivities of polarized colposcopic annotations for discriminating cervical intraepithelial neoplasia (CIN) 2 or higher were greater for all 3 acetowhite categories when compared with unpolarized annotations (58% [44/76] vs 45% [34/76], 68% [50/74] vs 59% [45/76], and 68% [49/72] vs 66% [50/76], respectively). The average percent differences in Euclidean distances between the epithelial types for unpolarized and polarized cervical images were as follows: CIN 2/3 versus CIN 1 = 33% (10/30, p =.03), CIN 2/3 versus columnar epithelium = 22% (p =.004), CIN 2/3 versus immature metaplasia = 29% (14/47, p =.11), and CIN 1 versus immature metaplasia = 27% (4.4/16, p =.16). Because of its ability to interrogate at a deeper plane and eliminate obscuring glare, polarized light colposcopy may enhance the evaluation and detection of cervical neoplasias.

  16. Enhancing electron diffraction through precession

    Energy Technology Data Exchange (ETDEWEB)

    Pavia, Giuseppe; Benner, Gerd; Niebel, Harald [Carl Zeiss NTS, Oberkochen (Germany); Patout, Loic [ONERA, Paris (France)

    2011-07-01

    Nanostructures are often investigated in Transmission Electron Microscopy (TEM), and electron diffraction (ED) can be used to solve nanocrystals. Electrons interact very strongly with matter, and the diffracted intensities are highly dynamical. Precession Electron Diffraction (PED) is a recent technique delivering more kinematical diffraction patterns. We have used an in column energy filtered TEM equipped with precession electron diffraction hardware, which allows working up to 3 precession angle, and energy filtering of the precession patterns. High Order Laue Zones, useful for space group symmetry determination and to enhance fine structure details, appear more clearly. We have compared a microdiffraction pattern and a precession microdiffraction pattern performed along the orientation [010] of a sample TiSi{sub 2} with a space group Fddd. For cubic systems, this orientation allows to distinguish the Bravais lattice and the presence of glide mirrors. We show that with precession, we conserve the distinction of the gap and the difference of periodicity between the ZOLZ and the FOLZ is improved.

  17. Enhanced Eryptosis Following Gramicidin Exposure

    Directory of Open Access Journals (Sweden)

    Abaid Malik

    2015-04-01

    Full Text Available The peptide antibiotic and ionophore gramicidin has previously been shown to trigger apoptosis of nucleated cells. In analogy to apoptosis, the suicidal death of erythrocytes or eryptosis involves cell shrinkage and cell membrane scrambling with phosphatidylserine translocation to the erythrocyte surface. Triggers of eryptosis include oxidative stress, increase of cytosolic Ca2+ activity ([Ca2+]i, and ceramide. The present study explored, whether gramicidin triggers eryptosis. To this end phosphatidylserine exposure at the cell surface was estimated from annexin V binding, cell volume from forward scatter, red blood cell distribution width (RDW from electronic particle counting, reactive oxidant species (ROS from 2',7'-dichlorodihydrofluorescein diacetate (DCFDA fluorescence, [Ca2+]i from Fluo3- and Fluo4 fluorescence, and ceramide abundance from binding of specific antibodies. As a result, a 24 h exposure of human erythrocytes to gramicidin significantly increased the percentage of annexin-V-binding cells (≥1 µg/mL, forward scatter (≥0.5 µg/mL and hemolysis. Gramicidin enhanced ROS activity, [Ca2+]i and ceramide abundance at the erythrocyte surface. The stimulation of annexin-V-binding by gramicidin was significantly blunted but not abolished by removal of extracellular Ca2+. In conclusion, gramicidin stimulates phospholipid scrambling of the erythrocyte cell membrane, an effect at least partially due to induction of oxidative stress, increase of [Ca2+]i and up-regulation of ceramide abundance. Despite increase of [Ca2+]i, gramicidin increases cell volume and slightly reduces RWD.

  18. Enhanced eryptosis following gramicidin exposure.

    Science.gov (United States)

    Malik, Abaid; Bissinger, Rosi; Liu, Guoxing; Liu, Guilai; Lang, Florian

    2015-04-23

    The peptide antibiotic and ionophore gramicidin has previously been shown to trigger apoptosis of nucleated cells. In analogy to apoptosis, the suicidal death of erythrocytes or eryptosis involves cell shrinkage and cell membrane scrambling with phosphatidylserine translocation to the erythrocyte surface. Triggers of eryptosis include oxidative stress, increase of cytosolic Ca2+ activity ([Ca2+]i), and ceramide. The present study explored, whether gramicidin triggers eryptosis. To this end phosphatidylserine exposure at the cell surface was estimated from annexin V binding, cell volume from forward scatter, red blood cell distribution width (RDW) from electronic particle counting, reactive oxidant species (ROS) from 2',7'-dichlorodihydrofluorescein diacetate (DCFDA) fluorescence, [Ca2+]i from Fluo3- and Fluo4 fluorescence, and ceramide abundance from binding of specific antibodies. As a result, a 24 h exposure of human erythrocytes to gramicidin significantly increased the percentage of annexin-V-binding cells (≥1 µg/mL), forward scatter (≥0.5 µg/mL) and hemolysis. Gramicidin enhanced ROS activity, [Ca2+]i and ceramide abundance at the erythrocyte surface. The stimulation of annexin-V-binding by gramicidin was significantly blunted but not abolished by removal of extracellular Ca2+. In conclusion, gramicidin stimulates phospholipid scrambling of the erythrocyte cell membrane, an effect at least partially due to induction of oxidative stress, increase of [Ca2+]i and up-regulation of ceramide abundance. Despite increase of [Ca2+]i, gramicidin increases cell volume and slightly reduces RWD.

  19. Ultrasound enhanced thrombolysis: Clinical evidence

    Science.gov (United States)

    Alexandrov, Andrei V.

    2005-04-01

    Phase II CLOTBUST randomized clinical trial (Houston, Barcelona, Edmonton, Calgary) evaluated patients with acute ischemic stroke due to intracranial occlusion and treated with intravenous tissue plasminogen activator (TPA) within 3 h of symptom onset. Randomization: monitoring with pulsed wave 2 MHz transcranial Doppler (TCD) (Target) or placebo monitoring (Control). Safety: symptomatic bleeding to the brain (sICH). Primary end-point: complete recanalization on TCD or dramatic clinical recovery by the total NIHSS score 10 NIHSS points within 2 hours after TPA bolus. All projected 126 patients were randomized 1:1 to target (median NIHSS 16) or control (NIHSS 17). sICH: 4.8% Target, 4.8% Controls. Primary end-point was achieved by 31 (49%, Target) versus 19 (30%, Control), p<0.03. At 3 months, 22 (42% Target) and 14 (29% Control) patients achieved favorable outcomes. Continuous TCD monitoring of intracranial occlusion safely augments TPA-induced arterial recanalization, and 2 MHz diagnostic ultrasound has a positive biological activity that aids systemic thrombolytic therapy. For the first time in clinical medicine, the CLOTBUST trial provides the evidence that ultrasound enhances thrombolytic activity of a drug in humans thereby confirming intense multi-disciplinary experimental research conducted worldwide for the past 30 years.

  20. An enhanced tokamak startup model

    Science.gov (United States)

    Goswami, Rajiv; Artaud, Jean-François

    2017-01-01

    The startup of tokamaks has been examined in the past in varying degree of detail. This phase typically involves the burnthrough of impurities and the subsequent rampup of plasma current. A zero-dimensional (0D) model is most widely used where the time evolution of volume averaged quantities determines the detailed balance between the input and loss of particle and power. But, being a 0D setup, these studies do not take into consideration the co-evolution of plasma size and shape, and instead assume an unchanging minor and major radius. However, it is known that the plasma position and its minor radius can change appreciably as the plasma evolves in time to fill in the entire available volume. In this paper, an enhanced model for the tokamak startup is introduced, which for the first time takes into account the evolution of plasma geometry during this brief but highly dynamic period by including realistic one-dimensional (1D) effects within the broad 0D framework. In addition the effect of runaway electrons (REs) has also been incorporated. The paper demonstrates that the inclusion of plasma cross section evolution in conjunction with REs plays an important role in the formation and development of tokamak startup. The model is benchmarked against experimental results from ADITYA tokamak.

  1. Advanced integrated enhanced vision systems

    Science.gov (United States)

    Kerr, J. R.; Luk, Chiu H.; Hammerstrom, Dan; Pavel, Misha

    2003-09-01

    In anticipation of its ultimate role in transport, business and rotary wing aircraft, we clarify the role of Enhanced Vision Systems (EVS): how the output data will be utilized, appropriate architecture for total avionics integration, pilot and control interfaces, and operational utilization. Ground-map (database) correlation is critical, and we suggest that "synthetic vision" is simply a subset of the monitor/guidance interface issue. The core of integrated EVS is its sensor processor. In order to approximate optimal, Bayesian multi-sensor fusion and ground correlation functionality in real time, we are developing a neural net approach utilizing human visual pathway and self-organizing, associative-engine processing. In addition to EVS/SVS imagery, outputs will include sensor-based navigation and attitude signals as well as hazard detection. A system architecture is described, encompassing an all-weather sensor suite; advanced processing technology; intertial, GPS and other avionics inputs; and pilot and machine interfaces. Issues of total-system accuracy and integrity are addressed, as well as flight operational aspects relating to both civil certification and military applications in IMC.

  2. Completely Enhanced Cell Phone Keypad

    CERN Document Server

    Sharmeen, Rezwana; Ahmad, Shabbir; Kamruzzaman, S M

    2010-01-01

    The enhanced frequency based keypad is designed to speed up the typing process. This paper will show that the proposed layout will increase the typing speed and be flexible for thumb. Traditional cell phone keypad is not a scientific keypad from the frequency point of view. Approaches have been explored to speed up the typing process. We found that no manufacturer has considered the frequency of the alphabet. The current architecture does not provide flexibility although the users are accustomed to the currently available multi-tapping keypad. Since the currently available keypad layouts are not best suited for users, this paper will suggest a keypad for cell phone and other cellular device based on the frequency of the alphabet in English language and also with the view of structure of human finger movements to provide a flexible and fast cell phone keypad. It also takes into consideration the key jamming problem that was available in typewriter. At first we identified those keys of cell phone, which are eas...

  3. Advanced hyperspectral imaging system with edge enhancement

    Science.gov (United States)

    Yushkov, K. B.; Molchanov, V. Y.

    2017-03-01

    We developed an acousto-optic hyperspectral imaging system with edge enhancement capability. The system is an add-on to a standard light microscope. Edge enhancement operation mode is aimed for analysis of low-contrast microscopic samples, e.g. unstained cytological smears and histological samples, live cells. Edge-enhancement imaging mode is based on a feature of acousto-optic tunable filters to perform band-pass spatial filtering when unturned from noncritical phase matching geometry is diffraction. Switching between standard hyperspectral imaging and edge-enhancement modes is performed by means of a telecentric amplitude mask.

  4. An Integrated Environmental Biotechnology for Enhanced ...

    African Journals Online (AJOL)

    An Integrated Environmental Biotechnology for Enhanced Bioremediation of Crude Oil ... nitrogen fixation and cometabolism of solubilized petroleum hydrocarbons. ... suggests a significant soil fertility recovery to warrant immediate cultivation.

  5. Lift enhancement by trapped vortex

    Science.gov (United States)

    Rossow, Vernon J.

    1992-01-01

    The viewgraphs and discussion of lift enhancement by trapped vortex are provided. Efforts are continuously being made to find simple ways to convert wings of aircraft from an efficient cruise configuration to one that develops the high lift needed during landing and takeoff. The high-lift configurations studied here consist of conventional airfoils with a trapped vortex over the upper surface. The vortex is trapped by one or two vertical fences that serve as barriers to the oncoming stream and as reflection planes for the vortex and the sink that form a separation bubble on top of the airfoil. Since the full three-dimensional unsteady flow problem over the wing of an aircraft is so complicated that it is hard to get an understanding of the principles that govern the vortex trapping process, the analysis is restricted here to the flow field illustrated in the first slide. It is assumed that the flow field between the two end plates approximates a streamwise strip of the flow over a wing. The flow between the endplates and about the airfoil consists of a spanwise vortex located between the suction orifices in the endplates. The spanwise fence or spoiler located near the nose of the airfoil serves to form a separated flow region and a shear layer. The vorticity in the shear layer is concentrated into the vortex by withdrawal of fluid at the suction orifices. As the strength of the vortex increases with time, it eventually dominates the flow in the separated region so that a shear or vertical layer is no longer shed from the tip of the fence. At that point, the vortex strength is fixed and its location is such that all of the velocity contributions at its center sum to zero thereby making it an equilibrium point for the vortex. The results of a theoretical analysis of such an idealized flow field are described.

  6. Enhancing Ocean Research Data Access

    Science.gov (United States)

    Chandler, Cynthia; Groman, Robert; Shepherd, Adam; Allison, Molly; Arko, Robert; Chen, Yu; Fox, Peter; Glover, David; Hitzler, Pascal; Leadbetter, Adam; Narock, Thomas; West, Patrick; Wiebe, Peter

    2014-05-01

    The Biological and Chemical Oceanography Data Management Office (BCO-DMO) works in partnership with ocean science investigators to publish data from research projects funded by the Biological and Chemical Oceanography Sections and the Office of Polar Programs Antarctic Organisms & Ecosystems Program at the U.S. National Science Foundation. Since 2006, researchers have been contributing data to the BCO-DMO data system, and it has developed into a rich repository of data from ocean, coastal and Great Lakes research programs. While the ultimate goal of the BCO-DMO is to ensure preservation of NSF funded project data and to provide open access to those data, achievement of those goals is attained through a series of related phases that benefits from active collaboration and cooperation with a large community of research scientists as well as curators of data and information at complementary data repositories. The BCO-DMO is just one of many intermediate data management centers created to facilitate long-term preservation of data and improve access to ocean research data. Through partnerships with other data management professionals and active involvement in local and global initiatives, BCO-DMO staff members are working to enhance access to ocean research data available from the online BCO-DMO data system. Continuing efforts in use of controlled vocabulary terms, development of ontology design patterns and publication of content as Linked Open Data are contributing to improved discovery and availability of BCO-DMO curated data and increased interoperability of related content available from distributed repositories. We will demonstrate how Semantic Web technologies (e.g. RDF/XML, SKOS, OWL and SPARQL) have been integrated into BCO-DMO data access and delivery systems to better serve the ocean research community and to contribute to an expanding global knowledge network.

  7. Protocolized hyperventilation enhances electroconvulsive therapy.

    Science.gov (United States)

    de Arriba-Arnau, Aida; Dalmau, Antonia; Soria, Virginia; Salvat-Pujol, Neus; Ribes, Carmina; Sánchez-Allueva, Ana; Menchón, José Manuel; Urretavizcaya, Mikel

    2017-08-01

    Hyperventilation is recommended in electroconvulsive therapy (ECT) to enhance seizures and to increase patients' safety. However, more evidence is needed regarding its effects and the optimum method of application. This prospective study involving 21 subjects compared two procedures, protocolized hyperventilation (PHV) and hyperventilation as usual (HVau), applied to the same patient in two consecutive sessions. Transcutaneous partial pressure of carbon dioxide (TcPCO2) was measured throughout all sessions. Ventilation parameters, hemodynamic measures, seizure characteristics, and side effects were also explored. PHV resulted in lower TcPCO2 after hyperventilation (p=.008) and over the whole session (p=.035). The lowest TcPCO2 was achieved after voluntary hyperventilation. Changes in TcPCO2 from baseline showed differences between HVau and PHV at each session time-point (all p<.05). Between- and within-subjects factors were statistically significant in a general linear model. Seizure duration was greater in PHV sessions (p=.028), without differences in other seizure quality parameters or adverse effects. Correlations were found between hypocapnia induction and seizure quality indexes. Secondary outcomes could be underpowered. PHV produces hypocapnia before the stimulus, modifies patients' TcPCO2 values throughout the ECT session and lengthens seizure duration. Voluntary hyperventilation is the most important part of the PHV procedure with respect to achieving hypocapnia. A specific ventilation approach, CO2 quantification and monitoring may be advisable in ECT. PHV is easy to apply in daily clinical practice and does not imply added costs. Ventilation management has promising effects in terms of optimizing ECT technique. Copyright © 2017 Elsevier B.V. All rights reserved.

  8. Electronic enhancement of tear secretion

    Science.gov (United States)

    Brinton, Mark; Lim Chung, Jae; Kossler, Andrea; Kook, Koung Hoon; Loudin, Jim; Franke, Manfred; Palanker, Daniel

    2016-02-01

    Objective. To study electrical stimulation of the lacrimal gland and afferent nerves for enhanced tear secretion, as a potential treatment for dry eye disease. We investigate the response pathways and electrical parameters to safely maximize tear secretion. Approach. We evaluated the tear response to electrical stimulation of the lacrimal gland and afferent nerves in isofluorane-anesthetized rabbits. In acute studies, electrical stimulation was performed using bipolar platinum foil electrodes, implanted beneath the inferior lacrimal gland, and a monopolar electrode placed near the afferent ethmoid nerve. Wireless microstimulators with bipolar electrodes were implanted beneath the lacrimal gland for chronic studies. To identify the response pathways, we applied various pharmacological inhibitors. To optimize the stimulus, we measured tear secretion rate (Schirmer test) as a function of pulse amplitude (1.5-12 mA), duration (0.1-1 ms) and repetition rate (10-100 Hz). Main results. Stimulation of the lacrimal gland increased tear secretion by engaging efferent parasympathetic nerves. Tearing increased with stimulation amplitude, pulse duration and repetition rate, up to 70 Hz. Stimulation with 3 mA, 500 μs pulses at 70 Hz provided a 4.5 mm (125%) increase in Schirmer score. Modulating duty cycle further increased tearing up to 57%, compared to continuous stimulation in chronically implanted animals (36%). Ethmoid (afferent) nerve stimulation increased tearing similar to gland stimulation (3.6 mm) via a reflex pathway. In animals with chronically implanted stimulators, a nearly 6 mm increase (57%) was achieved with 12-fold less charge density per pulse (0.06-0.3 μC mm-2 with 170-680 μs pulses) than the damage threshold (3.5 μC mm-2 with 1 ms pulses). Significance. Electrical stimulation of the lacrimal gland or afferent nerves may be used as a treatment for dry eye disease. Clinical trials should validate this approach in patients with aqueous tear deficiency, and

  9. Robotically enhanced rubber hand illusion.

    Science.gov (United States)

    Arata, Jumpei; Hattori, Masashi; Ichikawa, Shohei; Sakaguchi, Masamichi

    2014-01-01

    The rubber hand illusion is a well-known multisensory illusion. In brief, watching a rubber hand being stroked by a paintbrush while one's own unseen hand is synchronously stroked causes the rubber hand to be attributed to one's own body and to "feel like it's my hand." The rubber hand illusion is thought to be triggered by the synchronized tactile stimulation of both the subject's hand and the fake hand. To extend the conventional rubber hand illusion, we introduce robotic technology in the form of a master-slave telemanipulator. The developed one degree-of-freedom master-slave system consists of an exoskeleton master equipped with an optical encoder that is worn on the subject's index finger and a motor-actuated index finger on the rubber hand, which allows the subject to perform unilateral telemanipulation. The moving rubber hand illusion has been studied by several researchers in the past with mechanically connected rigs between the subject's body and the fake limb. The robotic instruments let us investigate the moving rubber hand illusion with less constraints, thus behaving closer to the classic rubber hand illusion. In addition, the temporal delay between the body and the fake limb can be precisely manipulated. The experimental results revealed that the robotic instruments significantly enhance the rubber hand illusion. The time delay is significantly correlated with the effect of the multisensory illusion, and the effect significantly decreased at time delays over 100 ms. These findings can potentially contribute to the investigations of neural mechanisms in the field of neuroscience and of master-slave systems in the field of robotics.

  10. Radial keratotomy enhancements for residual myopia.

    Science.gov (United States)

    Gayton, J L; Van der Karr, M; Sanders, V

    1997-01-01

    A systematic method of performing radial keratotomy enhancements in undercorrected eyes may increase accuracy and predictability and decrease the number of procedures required. A consecutive series of 372 radial keratotomy procedures, including 110 eyes that received enhancements under a systematic protocol, was evaluated. Radial keratotomy was performed using the Reliable Keratotomy software, which uses the Thornton nomogram for primary radial keratotomy and provides a systematic method of performing enhancements. Ninety eyes (24%) received one enhancement, 16 eyes (4%) received two enhancements, and four eyes (1%) received three enhancements. Mean final spherical equivalent refraction was -0.44 D (-4.00 to +1.875 D, SD 0.86) for eyes that did not receive enhancements and -0.44 D (-2.50 to +1.00 D, SD 0.61) for eyes that had enhancements. Mean final residual myopia for the entire cohort was -0.44 D (-4.00 to +1.875 D, SD 0.79). At final examination, 242 (65%) eyes had a refraction within +/- 0.5 D and 298 (80%) within +/- 1.00. Among eyes that received enhancements, 75 (68%) had a refraction within +/- 0.50 D, and 89 (81%) within +/- 1.00 D; 40 eyes (36%) had uncorrected visual acuity of 20/20 or better, 99 eyes (90%) 20/40 or better, and all but one eye (99%) 20/80 or better at the final postoperative examination. Among the entire cohort, 130 eyes (35%) had uncorrected visual acuity of 20/20 or better, 312 (84%) had 20/40 or better, and 350 (94%) had 20/80 or better. No eye lost more than one line of spectacle-corrected visual acuity. A systematic approach to enhancement of undercorrected eyes after radial keratotomy, combined with accurate surgery, may reduce the need for multiple enhancements as well as the overcorrection rate, and provide improved uncorrected visual acuity.

  11. UV fluorescence enhancement from nanostructured aluminum materials

    Science.gov (United States)

    Montanari, Danielle E.; Dean, Nathan; Poston, Pete E.; Blair, Steve; Harris, Joel M.

    2016-09-01

    Interest in label-free detection of biomolecules has given rise to the need for UV plasmonic materials. DNA bases and amino acid residues have electronic resonances in the UV which allow for sensitive detection of these species by surface-enhanced UV fluorescence spectroscopy. Electrochemical roughening has been used extensively to generate plasmonically-active metal surfaces that produce localized enhancement of excitation and emission of electromagnetic radiation from surface-bound molecules. Electrochemically roughened gold and silver surfaces produce enhancement in the visible and near-IR regions, but to the best of our knowledge, application of this technique for producing UV-enhancing substrates has not been reported. Using electropolishing of aluminum, we are able to generate nanostructured surfaces that produce enhanced spectroscopic detection of molecules in the UV. Aluminum is a natural choice for substrate composition as it exhibits a relatively large quality factor in the UV. We have fabricated electropolished aluminum films with nanometer scale roughness and have studied UV-excited fluorescence enhancement from submonolayer coverage of tryptophan on these substrates using a UV-laser based spectrometer. Quantitative dosing by dip-coating was used to deposit known surface concentrations of the aromatic amino acid tryptophan, so that fluorescence enhancement could be evaluated. Compared to a dielectric substrate (surface-oxidized silicon), we observe a 180-fold enhancement in the total fluorescence emitted by tryptophan on electropolished aluminum under photobleaching conditions, allowing detection of sub-monolayer coverages of molecules essential for development of biosensor technologies.

  12. Enhancing Engineering Education through Engineering Management

    Science.gov (United States)

    Pence, Kenneth R.; Rowe, Christopher J.

    2012-01-01

    Engineering Management courses are added to a traditional engineering curriculum to enhance the value of an undergraduate's engineering degree. A four-year engineering degree often leaves graduates lacking in business and management acumen. Engineering management education covers topics enhancing the value of new graduates by teaching management…

  13. Bacterial mutants for enhanced succinate production

    NARCIS (Netherlands)

    Baart, G.J.E.; Beauprez, J.J.R.; Foulquie, M.M.R.; Heijnen, J.J.; Maertens, J.

    2010-01-01

    The present invention relates to a method for obtaining enhanced metabolite production in micro-organisms, and to mutants and/or transformants obtained with said method. More particularly, it relates to bacterial mutants and/or transformants for enhanced succinate production, especially mutants and/

  14. Enhancing critical current density of cuprate superconductors

    Science.gov (United States)

    Chaudhari, Praveen

    2015-06-16

    The present invention concerns the enhancement of critical current densities in cuprate superconductors. Such enhancement of critical current densities include using wave function symmetry and restricting movement of Abrikosov (A) vortices, Josephson (J) vortices, or Abrikosov-Josephson (A-J) vortices by using the half integer vortices associated with d-wave symmetry present in the grain boundary.

  15. Open Educational Practices for Curriculum Enhancement

    Science.gov (United States)

    Armellini, Alejandro; Nie, Ming

    2013-01-01

    Open educational resources (OER) and open educational practices (OEP) are relatively new areas in educational research. How OER and OEP can help practitioners enhance curricula is one of a number of under-researched topics. This article aims to enable practitioners to identify and implement appropriate open practices to enhance higher education…

  16. Learning To Make Music Enhances Spatial Reasoning.

    Science.gov (United States)

    Hetland, Lois

    2000-01-01

    Examines whether active instruction in music enhances preschool and elementary school student performance on spatial tasks. Reports that music enhances the spatial-temporal performance of children during and up to two years following the instruction and that the effect is moderate and consistent. Includes references. (CMK)

  17. Sensor fusion method for machine performance enhancement

    Energy Technology Data Exchange (ETDEWEB)

    Mou, J.I. [Arizona State Univ., Tempe, AZ (United States); King, C.; Hillaire, R. [Sandia National Labs., Livermore, CA (United States). Integrated Manufacturing Systems Center; Jones, S.; Furness, R. [Ford Motor Co., Dearborn, MI (United States)

    1998-03-01

    A sensor fusion methodology was developed to uniquely integrate pre-process, process-intermittent, and post-process measurement and analysis technology to cost-effectively enhance the accuracy and capability of computer-controlled manufacturing equipment. Empirical models and computational algorithms were also developed to model, assess, and then enhance the machine performance.

  18. Conceptual and practical problems of moral enhancement.

    Science.gov (United States)

    Beck, Birgit

    2015-05-01

    Recently, the debate on human enhancement has shifted from familiar topics like cognitive enhancement and mood enhancement to a new and - to no one's surprise - controversial subject, namely moral enhancement. Some proponents from the transhumanist camp allude to the 'urgent need' of improving the moral conduct of humankind in the face of ever growing technological progress and the substantial dangers entailed in this enterprise. Other thinkers express more sceptical views about this proposal. As the debate has revealed so far, there is no shared opinion among philosophers (or scientists) about the meaning, prospects, and ethical evaluation of moral enhancement. In this article I will address several conceptual and practical problems of this issue, in order to encourage discussion about the prospects of (thinking about) moral enhancement in the future. My assumption is that (i) for the short term, there is little chance of arriving at an agreement on the proper understanding of morality and the appropriateness of one single (meta-)ethical theory; (ii) apart from this, there are further philosophical puzzles loosely referred to in the debate which add to theoretical confusion; and (iii) even if these conceptual problems could be solved, there are still practical problems to be smoothed out if moral enhancement is ever to gain relevance apart from merely theoretical interest. My tentative conclusion, therefore, will be that moral enhancement is not very likely to be made sense of - let alone realized - in the medium-term future. © 2014 John Wiley & Sons Ltd.

  19. Quality Enhancement and Educational Professional Development

    Science.gov (United States)

    Knight, Peter

    2006-01-01

    There is a strong international interest in the enhancement of teaching quality. Enhancement is a big job because teaching is an extensive activity. It is a complex job because learning to teach is not, mainly, a formal process: non-formal, practice-based learning is more significant. These two points, extensiveness and practice-based learning,…

  20. Teachers as designers of technology enhanced learning

    NARCIS (Netherlands)

    Kali, Yael; McKenney, Susan; Sagy, Ornit

    2013-01-01

    Kali, Y., McKenney, S., & Sagy, O. (2012, 2-6 July). Teachers as designers of technology enhanced learning. Presentation at the Teachers as Designers of Technology Enhanced Learning pre-conference workshop in conjunction with the ISLS annual meeting, Sydney, Australia.

  1. Nanoparticle Based Surface-Enhanced Raman Spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Talley, C E; Huser, T R; Hollars, C W; Jusinski, L; Laurence, T; Lane, S M

    2005-01-03

    Surface-enhanced Raman scattering is a powerful tool for the investigation of biological samples. Following a brief introduction to Raman and surface-enhanced Raman scattering, several examples of biophotonic applications of SERS are discussed. The concept of nanoparticle based sensors using SERS is introduced and the development of these sensors is discussed.

  2. Enhanced Controlled Transdermal Delivery of Torasemide Using ...

    African Journals Online (AJOL)

    Erah

    Purpose: To develop an ethylene-vinyl acetate (EVA) matrix system containing ... Methods: The solubility of torasemide was studied at various volume fraction of polyethylene glycol ... matrix across the skin, enhancers (propylene glycol derivatives, fatty acids, glycerides, pyrrolidones and ..... penetration enhancer is feasible.

  3. The Enhancement of Social Self-Esteem.

    Science.gov (United States)

    Marshall, W. L.; Christie, M. M.

    1982-01-01

    Compared the relative effectiveness of three self-management procedures in enhancing self-esteem. Results indicated that it is possible to enhance reported self-esteem by self-management procedures and that cueing effects are as important as reinforcing effects. (KMF)

  4. Surface enhanced raman spectroscopy on chip

    DEFF Research Database (Denmark)

    Hübner, Jörg; Anhøj, Thomas Aarøe; Zauner, Dan;

    2007-01-01

    is projected onto a CCD element and visualized by a computer. To enhance the otherwise rather weak Raman signal, a nanosurface is prepared and a sample solutions is impregnated on this surface. The surface enhanced Raman signal is picked up using a Raman probe and coupled into the spectrometer via an optical...

  5. Image Enhancement By Partially Coherent Imaging

    Science.gov (United States)

    Rhodes, William T.; Koizumi, M.

    1983-04-01

    A partially coherent Koehler-illumination imaging system equipped with complementary masks in source and pupil planes can be used to perform image enhancement operations such as directional or non-directional edge enhancement and emphasis of spatial bandpass features. With many objects the use of complementary masks results in high-contrast images. Underlying principles are explained and preliminary experimental results presented.

  6. Surface-enhanced Raman spectroscopy: nonlocal limitations

    DEFF Research Database (Denmark)

    Toscano, Giuseppe; Raza, Søren; Xiao, Sanshui

    2012-01-01

    for our understanding of surface-enhanced Raman spectroscopy (SERS). The intrinsic length scale of the electron gas serves to smear out assumed field singularities, leaving the SERS enhancement factor finite, even for geometries with infinitely sharp features. For silver nanogroove structures, mimicked...

  7. Animal Behaviour: Friendship Enhances Trust in Chimpanzees.

    Science.gov (United States)

    Silk, Joan

    2016-01-25

    Individuals that participate in exchanges with delayed rewards can be exploited if their partners don't reciprocate. In humans, friendships are built on trust, and trust enhances cooperation. New evidence suggests that close social bonds also enhance trust in chimpanzees.

  8. 4-Aminothiophenol Strong SERS Signal Enhance-ment at Electro dep osited Silver Surface

    Institute of Scientific and Technical Information of China (English)

    Lenka Skantarova; Andrej Orinak; Renata Orinakova; Frantisek Lofaj

    2012-01-01

    Strong surface enhancement Raman spectroscopy signal of 4-aminothiophenol on silver substrate prepared by controlled electrodeposition is documented in this article. Enhancement factor was found to be affected not only by nanoparticle size, shape, orientation and spatial distribution, but also by interaction of Ag nanoparticles with thiol group of testing analyte. Self-assembled monolayers formation was contributed to this unique signal enhancement. The enhancement factor was established of 1.81×1014 .

  9. Molecular mechanism of the sweet taste enhancers.

    Science.gov (United States)

    Zhang, Feng; Klebansky, Boris; Fine, Richard M; Liu, Haitian; Xu, Hong; Servant, Guy; Zoller, Mark; Tachdjian, Catherine; Li, Xiaodong

    2010-03-01

    Positive allosteric modulators of the human sweet taste receptor have been developed as a new way of reducing dietary sugar intake. Besides their potential health benefit, the sweet taste enhancers are also valuable tool molecules to study the general mechanism of positive allosteric modulations of T1R taste receptors. Using chimeric receptors, mutagenesis, and molecular modeling, we reveal how these sweet enhancers work at the molecular level. Our data argue that the sweet enhancers follow a similar mechanism as the natural umami taste enhancer molecules. Whereas the sweeteners bind to the hinge region and induce the closure of the Venus flytrap domain of T1R2, the enhancers bind close to the opening and further stabilize the closed and active conformation of the receptor.

  10. Speech enhancement on smartphone voice recording

    Science.gov (United States)

    Tris Atmaja, Bagus; Nur Farid, Mifta; Arifianto, Dhany

    2016-11-01

    Speech enhancement is challenging task in audio signal processing to enhance the quality of targeted speech signal while suppress other noises. In the beginning, the speech enhancement algorithm growth rapidly from spectral subtraction, Wiener filtering, spectral amplitude MMSE estimator to Non-negative Matrix Factorization (NMF). Smartphone as revolutionary device now is being used in all aspect of life including journalism; personally and professionally. Although many smartphones have two microphones (main and rear) the only main microphone is widely used for voice recording. This is why the NMF algorithm widely used for this purpose of speech enhancement. This paper evaluate speech enhancement on smartphone voice recording by using some algorithms mentioned previously. We also extend the NMF algorithm to Kulback-Leibler NMF with supervised separation. The last algorithm shows improved result compared to others by spectrogram and PESQ score evaluation.

  11. Enhancing nanoparticle electrodynamics with gold nanoplate mirrors.

    Science.gov (United States)

    Yan, Zijie; Bao, Ying; Manna, Uttam; Shah, Raman A; Scherer, Norbert F

    2014-05-14

    Mirrors and optical cavities can modify and enhance matter-radiation interactions. Here we report that chemically synthesized Au nanoplates can serve as micrometer-size mirrors that enhance electrodynamic interactions. Because of their plasmonic properties, the Au nanoplates enhance the brightness of scattered light from Ag nanoparticles near the nanoplate surface in dark-field microscopy. More importantly, enhanced optical trapping and optical binding of Ag nanoparticles are demonstrated in interferometric optical traps created from a single laser beam and its reflection from individual Au nanoplates. The enhancement of the interparticle force constant is ≈20-fold more than expected from the increased intensity due to standing wave interference. We show that the additional stability for optical binding arises from the restricted axial thermal motion of the nanoparticles that couples to and reduces the fluctuations in the lateral plane. This new mechanism greatly advances the photonic synthesis of ultrastable nanoparticle arrays and investigation of their properties.

  12. Gabor filter based fingerprint image enhancement

    Science.gov (United States)

    Wang, Jin-Xiang

    2013-03-01

    Fingerprint recognition technology has become the most reliable biometric technology due to its uniqueness and invariance, which has been most convenient and most reliable technique for personal authentication. The development of Automated Fingerprint Identification System is an urgent need for modern information security. Meanwhile, fingerprint preprocessing algorithm of fingerprint recognition technology has played an important part in Automatic Fingerprint Identification System. This article introduces the general steps in the fingerprint recognition technology, namely the image input, preprocessing, feature recognition, and fingerprint image enhancement. As the key to fingerprint identification technology, fingerprint image enhancement affects the accuracy of the system. It focuses on the characteristics of the fingerprint image, Gabor filters algorithm for fingerprint image enhancement, the theoretical basis of Gabor filters, and demonstration of the filter. The enhancement algorithm for fingerprint image is in the windows XP platform with matlab.65 as a development tool for the demonstration. The result shows that the Gabor filter is effective in fingerprint image enhancement technology.

  13. Metal plasmon enhanced europium complex luminescence

    Energy Technology Data Exchange (ETDEWEB)

    Liu Feng [Department of Chemistry, Queen' s University, 90 Bader Lane, Kingston, Ontario, K7L 3N6 (Canada); Aldea, Gabriela [Department of Chemistry, Queen' s University, 90 Bader Lane, Kingston, Ontario, K7L 3N6 (Canada); Petru Poni Institute of Macromolecular Chemistry Iasi, Aleea Grigore Ghica Voda 41A, 700487 Iasi (Romania); Nunzi, Jean-Michel, E-mail: nunzijm@queensu.c [Department of Chemistry, Queen' s University, 90 Bader Lane, Kingston, Ontario, K7L 3N6 (Canada)

    2010-01-15

    The plasmon enhanced luminescence of a rare-earth complex Tris(6, 6, 7, 7, 8, 8, 8-heptafluoro-2, 2-dimethyl-3, 5-octanedionato) europium (Eu(fod){sub 3}) was investigated. A polyvinyl alcohol (PVA) thin film was successfully adopted as a spacer to separate the Eu complex from the silver island film (SIF), and five-fold enhancement of the radiative decay rate of the Eu complex on SIF was demonstrated based on the luminescence intensity and lifetime measurement. Investigation of the distance dependent luminescence indicates that 7 nm is an optimal distance for SIF enhanced Eu luminescence. Plasmon enhanced rare-earth luminescence based on an organic film spacer would find potential applications in plasmon enhanced organic light emitting diode (OLED) devices.

  14. ELECTROSTATICALLY ENHANCED BARRIER FILTER COLLECTION

    Energy Technology Data Exchange (ETDEWEB)

    John Erjavec; Michael D. Mann; Ryan Z. Knutson; Michael L. Swanson; Michael E. Collings

    2003-06-01

    electrostatically enhanced barrier filter collection (EBFC). This concept combines electrostatic precipitation (ESP) with candle filters in a single unit. Similar technology has been recently proven on a commercial scale for atmospheric applications, but needed to be tested at high temperatures and pressures. The synergy obtained by combining the two control technologies into a single system should actually reduce filter system capital and operating costs and make the system more reliable. More specifically, the ESP is expected to significantly reduce candle filter load and also to limit ash reintrainment, allowing for full recovery of baseline pressure drop during backpulsing of the filters.

  15. Gold nanodisc arrays as near infrared metal-enhanced fluorescence platforms with tuneable enhancement factors

    KAUST Repository

    Pang, J.

    2016-12-28

    Metal enhanced fluorescence (MEF) is a physical effect through which the near-field interaction of fluorophores with metallic nanoparticles can lead to large fluorescence enhancement. MEF can be exploited in many fluorescence-based biomedical applications, with potentially significant improvement in detection sensitivity and contrast enhancement. Offering lower autofluorescence and minimal photoinduced damage, the development of effective and multifunctional MEF platforms in the near-infrared (NIR) region, is particularly desirable. In this work, the enhancement of NIR fluorescence caused by interaction with regular arrays of cylindrical gold (Au) nanoparticles (nanodiscs), fabricated through nanosphere lithography, is reported. Significant MEF of up to 235 times is obtained, with tuneable enhancement factors. The effect of array structure on fluorescence enhancement is investigated by semi-quantitatively de-convoluting excitation enhancement from emission enhancement, and modelling the local electric field enhancement. By considering arrays of Au nanodiscs with the same extinction maximum, it is shown that the excitation enhancement, due to increased electric field, is not significantly different for the particle sizes and separation distances considered. Rather, it is seen that the emission from the fluorophore is strongly enhanced, and is dependent on the topography, in particular particle size. The results show that the structural characteristics of Au nanodisc arrays can be manipulated to tune their enhancement factor, and hence their sensitivity.

  16. Inflammation-sensitive super enhancers form domains of coordinately regulated enhancer RNAs.

    Science.gov (United States)

    Hah, Nasun; Benner, Chris; Chong, Ling-Wa; Yu, Ruth T; Downes, Michael; Evans, Ronald M

    2015-01-20

    Enhancers are critical genomic elements that define cellular and functional identity through the spatial and temporal regulation of gene expression. Recent studies suggest that key genes regulating cell type-specific functions reside in enhancer-dense genomic regions (i.e., super enhancers, stretch enhancers). Here we report that enhancer RNAs (eRNAs) identified by global nuclear run-on sequencing are extensively transcribed within super enhancers and are dynamically regulated in response to cellular signaling. Using Toll-like receptor 4 (TLR4) signaling in macrophages as a model system, we find that transcription of super enhancer-associated eRNAs is dynamically induced at most of the key genes driving innate immunity and inflammation. Unexpectedly, genes repressed by TLR4 signaling are also associated with super enhancer domains and accompanied by massive repression of eRNA transcription. Furthermore, we find each super enhancer acts as a single regulatory unit within which eRNA and genic transcripts are coordinately regulated. The key regulatory activity of these domains is further supported by the finding that super enhancer-associated transcription factor binding is twice as likely to be conserved between human and mouse than typical enhancer sites. Our study suggests that transcriptional activities at super enhancers are critical components to understand the dynamic gene regulatory network.

  17. Intravenous, contrast-enhanced MR colonography using air as endoluminal contrast agent: Impact on colorectal polyp detection.

    LENUS (Irish Health Repository)

    Keeling, Aoife N

    2012-02-01

    PURPOSE: To compare diagnostic accuracy and patient tolerance of MR colonography with intravenous contrast and luminal air (MRC) to conventional colonoscopy (CC). MATERIALS AND METHODS: IRB approval and written informed consent were obtained. Forty-six patients, both screening and symptomatic, underwent MRC followed by CC. The MRC technique employed 3D T1W spoiled gradient echo sequences performed after the administration of gadopenetate dimeglumine, with parallel imaging. The diagnostic accuracy and tolerance of patients for MRC was compared to CC. RESULTS: Twenty-four polyps were detected in eighteen patients with CC (5 polyps >\\/=10mm, 4 polyps 6-9mm, 15 polyps <\\/=5mm). MRC was 66.7% (12\\/18) sensitive and 96.4% (27\\/28) specific for polyp detection on a per-patient basis. When analyzed by polyp size, sensitivity and specificity of MRC was 100% (5\\/5) and 100% (19\\/19), respectively, for lesions greater than 10mm, 100% (4\\/4) and 100% (20\\/20) for lesions 6-9mm, and sensitivity of 20% (3\\/15) lesions less than 5mm. The sensitivity and specificity of MRC for detecting significant lesions (>6mm) was 100% (9\\/9) and 100% (15\\/15), respectively. Regarding tolerance of the exams, there were no significant differences between MRC and CC. Thirty-five percent (n=16) of patients preferred MRC as a future screening test compared to 33% (n=15) for CC. CONCLUSION: MRC using air as an intraluminal contrast agent is a feasible and well-tolerated technique for detecting colonic polyps >\\/=6mm in size. Further studies are warranted.

  18. Intravenous, contrast-enhanced MR colonography using air as endoluminal contrast agent: Impact on colorectal polyp detection.

    LENUS (Irish Health Repository)

    Keeling, Aoife N

    2010-12-03

    PURPOSE: To compare diagnostic accuracy and patient tolerance of MR colonography with intravenous contrast and luminal air (MRC) to conventional colonoscopy (CC). MATERIALS AND METHODS: IRB approval and written informed consent were obtained. Forty-six patients, both screening and symptomatic, underwent MRC followed by CC. The MRC technique employed 3D T1W spoiled gradient echo sequences performed after the administration of gadopenetate dimeglumine, with parallel imaging. The diagnostic accuracy and tolerance of patients for MRC was compared to CC. RESULTS: Twenty-four polyps were detected in eighteen patients with CC (5 polyps ≥10mm, 4 polyps 6-9mm, 15 polyps ≤5mm). MRC was 66.7% (12\\/18) sensitive and 96.4% (27\\/28) specific for polyp detection on a per-patient basis. When analyzed by polyp size, sensitivity and specificity of MRC was 100% (5\\/5) and 100% (19\\/19), respectively, for lesions greater than 10mm, 100% (4\\/4) and 100% (20\\/20) for lesions 6-9mm, and sensitivity of 20% (3\\/15) lesions less than 5mm. The sensitivity and specificity of MRC for detecting significant lesions (>6mm) was 100% (9\\/9) and 100% (15\\/15), respectively. Regarding tolerance of the exams, there were no significant differences between MRC and CC. Thirty-five percent (n=16) of patients preferred MRC as a future screening test compared to 33% (n=15) for CC. CONCLUSION: MRC using air as an intraluminal contrast agent is a feasible and well-tolerated technique for detecting colonic polyps ≥6mm in size. Further studies are warranted.

  19. Contrast Enhancement through Clustered Histogram Equalization

    Directory of Open Access Journals (Sweden)

    Shen-Chuan Tai

    2012-09-01

    Full Text Available This study proposed a contrast enhancement algorithm. Some methods enhance images depending on only the global or the local information, therefore it would cause over-enhancement usually and make the image look unnatural. The proposed method enhances image based on the global and local information. For the global part, we proposed mapping curves to find the new average, maximum and minimum intensity to try to suit the concept of Human Visual System (HVS for obtaining the better perceptual results. For the local part, we utilized fuzzy c-means clustering algorithm to group image and we can obtain the information of intensity distribution and pixel number from each group. Then we calculate weights according to the information and enhance images by Histogram Equalization (HE depending on the weights. The experiment results show that our method can enhance the contrast of image steadily and it causes over-enhancement with lower probability than other methods. The whole image not only looks natural but also shows detail texture more clearly after applying our method.

  20. Hyperthermia enhances CTL cross-priming.

    Science.gov (United States)

    Shi, Hongzhen; Cao, Tinghua; Connolly, John E; Monnet, Laurence; Bennett, Lynda; Chapel, Sylvie; Bagnis, Claude; Mannoni, Patrice; Davoust, Jean; Palucka, A Karolina; Banchereau, Jacques

    2006-02-15

    Dendritic cells (DCs) loaded with killed allogeneic melanoma cells can cross-prime naive CD8(+) T cells to differentiate into melanoma-specific CTLs in 3-wk cultures. In this study we show that DCs loaded with killed melanoma cells that were heated to 42 degrees C before killing are more efficient in cross-priming of naive CD8(+) T cells than DCs loaded with unheated killed melanoma cells. The enhanced cross-priming was demonstrated by several parameters: 1) induction of naive CD8(+) T cell differentiation in 2-wk cultures, 2) enhanced killing of melanoma peptide-pulsed T2 cells, 3) enhanced killing of HLA-A*0201(+) melanoma cells in a standard 4-h chromium release assay, and 4) enhanced capacity to prevent tumor growth in vitro in a tumor regression assay. Two mechanisms might explain the hyperthermia-induced enhanced cross-priming. First, heat-treated melanoma cells expressed increased levels of 70-kDa heat shock protein (HSP70), and enhanced cross-priming could be reproduced by overexpression of HSP70 in melanoma cells transduced with HSP70 encoding lentiviral vector. Second, hyperthermia resulted in the increased transcription of several tumor Ag-associated Ags, including MAGE-B3, -B4, -A8, and -A10. Thus, heat treatment of tumor cells permits enhanced cross-priming, possibly via up-regulation of both HSPs and tumor Ag expression.

  1. Evolution of Alu elements toward enhancers.

    Science.gov (United States)

    Su, Ming; Han, Dali; Boyd-Kirkup, Jerome; Yu, Xiaoming; Han, Jing-Dong J

    2014-04-24

    The human genome contains approximately one million Alu repetitive elements comprising 10% of the genome, yet their functions are not well understood. Here, we show that Alu elements resemble enhancers. Alu elements are bound by two well-phased nucleosomes that contain histones bearing marks of active chromatin, and they show tissue-specific enrichment for the enhancer mark H3K4me1. A proportion of Alu elements were experimentally validated as bona fide active enhancers with an in vitro reporter assay. In addition, Hi-C data indicate that Alus show long-range interactions with gene promoters. We also find that Alus are generally more conserved when located in the proximal upstream region of genes. Their similarity to enhancers becomes more prominent with their age in the human genome, following a clear evolutionary continuum reminiscent of the evolutionary pattern of proto-genes. Therefore, we conclude that some Alu elements can function as enhancers and propose that many more may be proto-enhancers that serve as a repertoire for the de novo birth of enhancers.

  2. Autoimmune pancreatitis: Assessment of the enhanced duct sign on multiphase contrast-enhanced computed tomography

    Energy Technology Data Exchange (ETDEWEB)

    Kawai, Yuichi, E-mail: kawai.yuichi@a.mbox.nagoya-u.ac.jp [Department of Radiology, Nagoya University Graduate School of Medicine, 65 Tsurumai-cho, Showa-ku, Nagoya 466-8550 (Japan); Suzuki, Kojiro, E-mail: kojiro@med.nagoya-u.ac.jp [Department of Radiology, Nagoya University Graduate School of Medicine, 65 Tsurumai-cho, Showa-ku, Nagoya 466-8550 (Japan); Itoh, Shigeki, E-mail: shigeito@nagoya-1st.jrc.or.jp [Department of Diagnostic Radiology, Japan Red Cross Nagoya Daiichi Hospital, 3-35 Michishita-cho, Nakamura-ku, Nagoya 453-8511 (Japan); Takada, Akira, E-mail: takadaa@med.nagoya-u.ac.jp [Department of Radiology, Nagoya University Graduate School of Medicine, 65 Tsurumai-cho, Showa-ku, Nagoya 466-8550 (Japan); Mori, Yoshine, E-mail: yoshine@med.nagoya-u.ac.jp [Department of Radiology, Nagoya University Graduate School of Medicine, 65 Tsurumai-cho, Showa-ku, Nagoya 466-8550 (Japan); Naganawa, Shinji, E-mail: naganawa@med.nagoya-u.ac.jp [Department of Radiology, Nagoya University Graduate School of Medicine, 65 Tsurumai-cho, Showa-ku, Nagoya 466-8550 (Japan)

    2012-11-15

    Purpose: To assess the usefulness of the computed tomography (CT) finding of main pancreatic duct (MPD) wall enhancement, termed the 'enhanced duct sign', for diagnosis of autoimmune pancreatitis (AIP) in comparison with diagnosis of pancreatic carcinoma and chronic pancreatitis. Materials and methods: Two radiologists independently evaluated the presence or absence of the enhanced duct sign on multiphase contrast-enhanced CT in patients with AIP (n = 55), pancreatic carcinoma (n = 50), and chronic pancreatitis (n = 50). The sensitivity, specificity, accuracy, positive predictive value, and negative predictive value of AIP were calculated. In patients demonstrating the enhanced duct sign, additional findings were evaluated by consensus. Results: The enhanced duct sign was more frequently observed in patients with AIP (37/55, 67%) than in patients with pancreatic carcinoma (5/50, 10%) or chronic pancreatitis (0/50, 0%) (P < 0.05). The sensitivity, specificity, accuracy, positive predictive value, and negative predictive value of the finding were 0.67, 0.95, 0.85, 0.88, and 0.84, respectively. In AIP, the lumen within the enhanced duct was completely or partially invisible in 29 of 37 (78%) patients, and the enhanced duct was observed within the affected pancreatic parenchyma in 35 of 37 (95%) patients. In pancreatic carcinoma, the lumen within the enhanced duct was visible in all patients (5/5, 100%), and the enhanced duct was observed downstream of the tumor (5/5, 100%). Conclusion: The enhanced duct sign is highly specific of AIP.

  3. [Study on cine view of relative enhancement ratio map in O2-enhanced MRI].

    Science.gov (United States)

    Fujii, Keita; Watanabe, Yasushi; Hanaoka, Shouhei; Motoyoshi, Kouichi; Goto, Masami; Amemiya, Shiori; Ino, Kenji; Akahane, Masaaki; Yano, Keiichi; Ohtomo, Kuni

    2014-11-01

    Magnetic resonance imaging (MRI) enables the evaluation of organ structure and function. Oxygen-enhanced MRI (O2-enhanced MRI) is a method for evaluating the pulmonary ventilation function using oxygen as a contrast agent. We created the Cine View of Relative Enhancement Ratio Map (Cine RER map) in O2-enhanced MRI to easily observe the contrast effect for clinical use. Relative enhancement ratio (RER) was determined as the pixel values of the Cine RER map. Moreover, six healthy volunteers underwent O2-enhanced MRI to determine the appropriate scale width of the Cine RER map. We calculated each RER and set 0 to 1.27 as the scale width of the Cine RER map based on the results. The Cine RER map made it possible to observe the contrast effect over time and thus is a convenient tool for evaluating the pulmonary ventilation function in O2-enhanced MRI.

  4. Patentability of methods of human enhancement

    DEFF Research Database (Denmark)

    Nordberg, Ana

    2015-01-01

    This article explores how to apply patentability rules to human enhancement, particularly focusing on Article 53(c) of the European Patent Convention (EPC). The global size and value of the cosmetic and wellness market and industry allow for the prediction of considerable market potential for human......, and subsequently developed through European Patent Office (EPO) case law, by reference to the dichotomy between therapeutic and cosmetic methods. Subsuming enhancement methods under this patentability rule may be challenging. Ultimately, patentability of human enhancement will depend on the concept of health, its...

  5. Fingerprint Verification based on Gabor Filter Enhancement

    CERN Document Server

    Lavanya, B N; Venugopal, K R

    2009-01-01

    Human fingerprints are reliable characteristics for personnel identification as it is unique and persistence. A fingerprint pattern consists of ridges, valleys and minutiae. In this paper we propose Fingerprint Verification based on Gabor Filter Enhancement (FVGFE) algorithm for minutiae feature extraction and post processing based on 9 pixel neighborhood. A global feature extraction and fingerprints enhancement are based on Hong enhancement method which is simultaneously able to extract local ridge orientation and ridge frequency. It is observed that the Sensitivity and Specificity values are better compared to the existing algorithms.

  6. Enhancing Rotational Diffusion Using Oscillatory Shear

    KAUST Repository

    Leahy, Brian D.

    2013-05-29

    Taylor dispersion - shear-induced enhancement of translational diffusion - is an important phenomenon with applications ranging from pharmacology to geology. Through experiments and simulations, we show that rotational diffusion is also enhanced for anisotropic particles in oscillatory shear. This enhancement arises from variations in the particle\\'s rotation (Jeffery orbit) and depends on the strain amplitude, rate, and particle aspect ratio in a manner that is distinct from the translational diffusion. This separate tunability of translational and rotational diffusion opens the door to new techniques for controlling positions and orientations of suspended anisotropic colloids. © 2013 American Physical Society.

  7. Fingerprint image enhancement using CNN filtering techniques.

    Science.gov (United States)

    Saatci, Ertugrul; Tavsanoglu, Vedat

    2003-12-01

    Due to noisy acquisition devices and variation in impression conditions, the ridgelines of fingerprint images are mostly corrupted by various kinds of noise causing cracks, scratches and bridges in the ridges as well as blurs. These cause matching errors in fingerprint recognition. For an effective recognition the correct ridge pattern is essential which requires the enhancement of fingerprint images. Segment by segment analysis of the fingerprint pattern yields various ridge direction and frequencies. By selecting a directional filter with correct filter parameters to match ridge features at each point, we can effectively enhance fingerprint ridges. This paper proposes a fingerprint image enhancement based on CNN Gabor-Type filters.

  8. Enhanced Gain in Photonic Crystal Amplifiers

    DEFF Research Database (Denmark)

    Ek, Sara; Semenova, Elizaveta; Hansen, Per Lunnemann;

    2012-01-01

    study of a 1 QW photonic crystal amplifier. Net gain is achieved which enables laser oscillation in photonic crystal micro cavities. The ability to freely tailor the dispersion in a semiconductor optical amplifier makes it possible to raise the optical gain considerably over a certain bandwidth......We experimentally demonstrate enhanced gain in the slow-light regime of quantum well photonic crystal amplifiers. A strong gain enhancement is observed with the increase of the group refractive index, due to light slow-down. The slow light enhancement is shown in a amplified spontaneous emission...

  9. Enhancer evolution across 20 mammalian species

    DEFF Research Database (Denmark)

    Villar, Diego; Berthelot, Camille; Aldridge, Sarah;

    2015-01-01

    The mammalian radiation has corresponded with rapid changes in noncoding regions of the genome, but we lack a comprehensive understanding of regulatory evolution in mammals. Here, we track the evolution of promoters and enhancers active in liver across 20 mammalian species from six diverse orders...... by profiling genomic enrichment of H3K27 acetylation and H3K4 trimethylation. We report that rapid evolution of enhancers is a universal feature of mammalian genomes. Most of the recently evolved enhancers arise from ancestral DNA exaptation, rather than lineage-specific expansions of repeat elements....... These results provide important insight into the functional genetics underpinning mammalian regulatory evolution....

  10. Enhancing Rotational Diffusion Using Oscillatory Shear

    Science.gov (United States)

    Leahy, Brian D.; Cheng, Xiang; Ong, Desmond C.; Liddell-Watson, Chekesha; Cohen, Itai

    2013-05-01

    Taylor dispersion—shear-induced enhancement of translational diffusion—is an important phenomenon with applications ranging from pharmacology to geology. Through experiments and simulations, we show that rotational diffusion is also enhanced for anisotropic particles in oscillatory shear. This enhancement arises from variations in the particle’s rotation (Jeffery orbit) and depends on the strain amplitude, rate, and particle aspect ratio in a manner that is distinct from the translational diffusion. This separate tunability of translational and rotational diffusion opens the door to new techniques for controlling positions and orientations of suspended anisotropic colloids.

  11. Recent studies of transform image enhancement

    Science.gov (United States)

    Aghagolzadeh, Sabzali; Ersoy, Okan K.

    1992-06-01

    Blockwise transform image enhancement techniques are discussed. It is shown that the best transforms for transform image coding, namely, the scrambled real discrete Fourier transform, the discrete cosine transform, and the discrete cosine-III transform, are also the best for image enhancement. Three techniques of enhancement discussed in detail are alpha- rooting, modified unsharp masking, and filtering motivated by the human visual system response (HVS). With proper modifications, it is observed that unsharp masking and HVS- motivated filtering without nonlinearities are basically equivalent. Block effects are completely removed by using an overlap-save technique in addition to the best transform.

  12. Separation enhancement in pinched flow fractionation

    DEFF Research Database (Denmark)

    Vig, Asger Laurberg; Kristensen, Anders

    2008-01-01

    A method for enhancing the separation in the microfluidic size separation technique called pinched flow fractionation (PFF) is demonstrated experimentally and analyzed by numerical calculations. The enhancement is caused by a geometrical modification of the original PFF design. Seven different...... polystyrene bead sizes ranging from 0.25 to 2.5 mu m in radius were separated in a PFF and in an enhanced PFF device. The separation in the two types of devices were compared and an amplification in the separation of up to 70% was achieved. Numerical calculations, which include an edge effect, are used...

  13. Highly Enhanced Risk Management Emergency Satellite

    DEFF Research Database (Denmark)

    Dalmeir, Michael; Gataullin, Yunir; Indrajit, Agung

    HERMES (Highly Enhanced Risk Management Emergency Satellite) is potential European satellite mission for global flood management, being implemented by Technical University Munich and European Space Agency. With its main instrument - a reliable and precise Synthetic Aperture Radar (SAR) antenna...

  14. polypyrrole/lignin composites for enhanced cha

    African Journals Online (AJOL)

    ENHANCED CHARGE STORAGE IN SUPERCAPACITORS ... renewable energy conversion technologies like solar and wind are intermittent [1-3]. ... containing biomaterials [12-16] significantly improve the energy storage capacity of SCs by.

  15. Indian, Swiss nuke centres to enhance

    CERN Multimedia

    2005-01-01

    India and a major European nuclear facility signed a Statement of Intent designed to significantly enhance existing levels of cooperation and give Indian scientists access to the latest in nuclear-related technology

  16. Enhancing learners’ visual search in video cases

    NARCIS (Netherlands)

    Balslev, Thomas; Jarodzka, Halszka; Holmqvist, Kenneth; Nyström, Marcus; Scheiter, Katharina; Gerjets, Peter; Eika, Berit

    2012-01-01

    Balslev, T., Jarodzka, H., Holmqvist, K., Nyström, M., Scheiter, K., Gerjets, P., & Eika, B. (2012, May). Enhancing learners’ visual search in video cases. Poster presented at the International Child Neurology Association (ICNA) congress, Brisbane, Australia.

  17. ENHANCING WRITING ABILITY THROUGH IDEA LISTING TECHNIQUE

    Directory of Open Access Journals (Sweden)

    M. Zaini Miftah

    2015-05-01

    Full Text Available The study is aimed at developing the Idea Listing Technique (ILT to enhance the students‟ writing ability. The Classroom Action Research was applied in this study. The subjects of the study were 31 students, the students taking the course of Writing II, of the third semester of English Department of one State Islamic College at Palangka Raya, Indonesia, in the 2012/2013 academic year. The findings show that the implementation of ILT can enhance the students‟ ability in writing expository paragraph. It is indicated by the enhancements of the percentage of the students achieving the score greater than or equal to C (60-69, and of the percentage of their involvement in the writing activities during the implementation of ILT in Cycle I and II. Thus, the enhancement of the students‟ ability in writing expository paragraph can be reached but it should follow the appropriate procedures of the implementation of ILT having been developed.

  18. Aerodynamic Efficiency Enhancements for Air Vehicles Project

    Data.gov (United States)

    National Aeronautics and Space Administration — The need for aerodynamics-based efficiency enhancements for air vehicles is presented. The results of the Phase I investigation of concepts for morphing aircraft are...

  19. Workplace Counselling: Implications For Enhanced Productivity ...

    African Journals Online (AJOL)

    Workplace Counselling: Implications For Enhanced Productivity. ... the provision of brief psychological therapy for employees of organizations. ... and concludes that increase in work related trauma and stress, accidents at the workplace, ...

  20. Fusion Enhanced Vehicle Level Diagnostic System Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Global Technology Connection, Inc. in conjunction with its partner, Vanderbilt University, is proposing to build a Fusion-enhanced Vehicle Diagnostics System (FVDS)...

  1. Gd enhanced MRI in sensorineural hearing loss

    Energy Technology Data Exchange (ETDEWEB)

    Takenaka, Mika; Tono, Tetsuya; Toyama, Katsuhiro; Kano, Kiyo; Morimitsu, Tamotsu [Miyazaki Medical Coll., Kiyotake (Japan)

    1996-09-01

    The enhanced MRI hearing findings of the inner ear in 124 patients with sensorineural hearing loss were evaluated. MR images were obtained before and after the intravenous administration of gadolinium (0.1 mmol/kg). In three out of seventy-nine patients with unilateral healing loss, cochlear and/or the vestibular enhancement was noted on the symptomatic side. The positive cases included those with Ramsay-Hunt syndrome, mumps and so-called sudden deafness. Forty-five patients with bilateral hearing loss showed no enhancement within the inner ear. Although positive gadolinium enhancement of the inner ear may detect inflammatory lesions due to a viral infection, its incidence in sensorineural hearing loss, including cases of sudden deafness. seems to be extremely rare. (author)

  2. Cavity-Enhanced Third Harmonic Generation

    Institute of Scientific and Technical Information of China (English)

    YANG Xiao-Xue; WU Ying

    2005-01-01

    We derive the analytical expression of microcavity-enhanced factor for third harmonic generation in terms of detunings, linewidths, and the Purcell factors of the relevant microcavity modes. It is suitable for microcavities with any dimensions and arbitrary geometric shapes.

  3. Large Purcell enhancement without strong field localization

    CERN Document Server

    Krasnok, Alexander; Petrov, Mihail; Makarov, Sergey; Savelev, Roman; Belov, Pavel; Simovski, Constantin; Kivshar, Yuri

    2015-01-01

    The Purcell effect is defined as the modification of spontaneous decay in the presence of a resonator, and in plasmonics it is usually associated with the large local-field enhancement in "hot spots" due to surface plasmon polaritons. Here we propose a novel strategy for enhancing the Purcell effect through engineering the radiation directivity without a strict requirement of the local field enhancement. Employing this approach, we demonstrate how to enhance the Purcell effect by two orders of magnitude in all-dielectric nanostructures recently suggested as building blocks of low-loss nanophotonics and metamaterials. We support our concept by proof-of-principle microwave experiments with arrays of high-index dielectric resonators.

  4. Coupled external cavity photonic crystal enhanced fluorescence.

    Science.gov (United States)

    Pokhriyal, Anusha; Lu, Meng; Ge, Chun; Cunningham, Brian T

    2014-05-01

    We report a fundamentally new approach to enhance fluorescence in which surface adsorbed fluorophore-tagged biomolecules are excited on a photonic crystal surface that functions as a narrow bandwidth and tunable mirror of an external cavity laser. This scheme leads to ∼10× increase in the electromagnetic enhancement factor compared to ordinary photonic crystal enhanced fluorescence. In our experiments, the cavity automatically tunes its lasing wavelength to the resonance wavelength of the photonic crystal, ensuring optimal on-resonance coupling even in the presence of variable device parameters and variations in the density of surface-adsorbed capture molecules. We achieve ∼10(5) × improvement in the limit of detection of a fluorophore-tagged protein compared to its detection on an unpatterned glass substrate. The enhanced fluorescence signal and easy optical alignment make cavity-coupled photonic crystals a viable approach for further reducing detection limits of optically-excited light emitters that are used in biological assays.

  5. Enhanced parametric processes in binary metamaterials

    OpenAIRE

    Gorkunov, Maxim V.; Shadrivov, Ilya V.; Kivshar, Yuri S.

    2005-01-01

    We suggest double-resonant (binary) metamaterials composed of two types of magnetic resonant elements, and demonstrate that in the nonlinear regime such metamaterials provide unique possibilities for phase-matched parametric interaction and enhanced second-harmonic generation.

  6. Teacher Design Knowledge for Technology Enhanced Learning

    NARCIS (Netherlands)

    McKenney-Jensh, Susan E.

    2014-01-01

    This presentation shares a framework for investigating the knowledge teachers need to be able to design technology-enhanced learning. Specific activities are undertaken to consider elements within the framework

  7. Entanglement Enhancement in an XY Spin Chain

    Institute of Scientific and Technical Information of China (English)

    SU Xiao-Qiang

    2011-01-01

    We study evolution of entanglement in an XY-type spin channel and find that the entanglement can be enhanced by the spin channel. The parameter regions of the initial states for different numbers of sites are obtained.Furthermore, we consider a common spin environment coupling to the spin chains and find that the entanglement enhancement can also be implemented only for the chains with the odd numbers of sites.%@@ We study evolution of entanglement in an XY-type spin channel and find that the entanglement can be enhanced by the spin channel.The parameter regions of the initial states for different numbers of sites are obtained.Furthermore,we consider a common spin environment coupling to the spin chains and find that the entanglement enhancement can also be implemented only for the chains with the odd numbers of sites.

  8. Signal enhancement with variable span linear filters

    CERN Document Server

    Benesty, Jacob; Jensen, Jesper R

    2016-01-01

    This book introduces readers to the novel concept of variable span speech enhancement filters, and demonstrates how it can be used for effective noise reduction in various ways. Further, the book provides the accompanying Matlab code, allowing readers to easily implement the main ideas discussed. Variable span filters combine the ideas of optimal linear filters with those of subspace methods, as they involve the joint diagonalization of the correlation matrices of the desired signal and the noise. The book shows how some well-known filter designs, e.g. the minimum distortion, maximum signal-to-noise ratio, Wiener, and tradeoff filters (including their new generalizations) can be obtained using the variable span filter framework. It then illustrates how the variable span filters can be applied in various contexts, namely in single-channel STFT-based enhancement, in multichannel enhancement in both the time and STFT domains, and, lastly, in time-domain binaural enhancement. In these contexts, the properties of ...

  9. Microwave Enhancement in Coronal Holes: Statistical Properties

    Indian Academy of Sciences (India)

    Ν. Gopalswamy; Κ. Shibasaki; Μ. Salem

    2000-09-01

    We report on the statistical properties of the microwave enhancement (brightness temperature, area, fine structure, life time and magnetic field strength) in coronal holes observed over a period of several solar rotations.

  10. Tailored nanoporous gold for ultrahigh fluorescence enhancement.

    Science.gov (United States)

    Lang, X Y; Guan, P F; Fujita, T; Chen, M W

    2011-03-07

    We report molecular fluorescence enhancement of free-standing nanoporous gold in which the nanoporosity can be arbitrarily tailored by the combination of dealloying and electroless gold plating. The nanoporous gold fabricated by this facile method possesses unique porous structures with large gold ligaments and very small pores, and exhibits significant improvements in surface enhanced fluorescence as well as structure rigidity. It demonstrates that the confluence effect of improved quantum yield and excitation of fluorophores is responsible for the large fluorescence enhancement due to the near-field enhancement of nanoporous gold, which arises from the strong electromagnetic coupling between neighboring ligaments and the weakening of plasmon damping of the large ligaments because of the small pore size and large ligament size, respectively.

  11. Enhanced Quantization: The particle on the circle

    CERN Document Server

    Geloun, Joseph Ben

    2012-01-01

    Enhanced quantization is an improved program for overcoming difficulties which may arise during an ordinary canonical quantization procedure. We review here how this program applies for a particle on circle.

  12. Hippocampal Processing of Ambiguity Enhances Fear Memory.

    Science.gov (United States)

    Amadi, Ugwechi; Lim, Seh Hong; Liu, Elizabeth; Baratta, Michael V; Goosens, Ki A

    2017-02-01

    Despite the ubiquitous use of Pavlovian fear conditioning as a model for fear learning, the highly predictable conditions used in the laboratory do not resemble real-world conditions, in which dangerous situations can lead to unpleasant outcomes in unpredictable ways. In the current experiments, we varied the timing of aversive events after predictive cues in rodents and discovered that temporal ambiguity of aversive events greatly enhances fear. During fear conditioning with unpredictably timed aversive events, pharmacological inactivation of the dorsal hippocampus or optogenetic silencing of cornu ammonis 1 cells during aversive negative prediction errors prevented this enhancement of fear without affecting fear learning for predictable events. Dorsal hippocampal inactivation also prevented ambiguity-related enhancement of fear during auditory fear conditioning under a partial-reinforcement schedule. These results reveal that information about the timing and occurrence of aversive events is rapidly acquired and that unexpectedly timed or omitted aversive events generate hippocampal signals to enhance fear learning.

  13. Scientific Research Enjoys Enhanced Support in China

    Institute of Scientific and Technical Information of China (English)

    2005-01-01

    @@ Scientific research in China is receiving enhanced support from both the government and the public, as science and technology are playing an increasingly constructive role in the country's social progress and economic growth, states CAS President Lu Yongxiang.

  14. Performance-Enhancing Drugs and Teen Athletes

    Science.gov (United States)

    Healthy Lifestyle Tween and teen health Performance-enhancing drugs can be tempting for teen athletes. Understand the warning signs and what you can do to keep your teen from using shortcuts to improve athletic performance. By Mayo ...

  15. Viability of Biopolymers for Enhanced Oil Recovery

    NARCIS (Netherlands)

    Sveistrup, Marte; van Mastrigt, Frank; Norrman, Jens; Picchioni, Francesco; Paso, Kristofer

    2016-01-01

    Xanthan gum and scleroglucan are assessed as environmentally friendly enhanced oil recovery (EOR) agents. Viscometric and interfacial tension measurements show that the polysaccharides exhibit favorable viscosifying performance, robust shear tolerance, electrolyte tolerance, and moderate interaction

  16. Enhancer evolution across 20 mammalian species

    DEFF Research Database (Denmark)

    Villar, Diego; Berthelot, Camille; Aldridge, Sarah;

    2015-01-01

    The mammalian radiation has corresponded with rapid changes in noncoding regions of the genome, but we lack a comprehensive understanding of regulatory evolution in mammals. Here, we track the evolution of promoters and enhancers active in liver across 20 mammalian species from six diverse orders...... by profiling genomic enrichment of H3K27 acetylation and H3K4 trimethylation. We report that rapid evolution of enhancers is a universal feature of mammalian genomes. Most of the recently evolved enhancers arise from ancestral DNA exaptation, rather than lineage-specific expansions of repeat elements....... In contrast, almost all liver promoters are partially or fully conserved across these species. Our data further reveal that recently evolved enhancers can be associated with genes under positive selection, demonstrating the power of this approach for annotating regulatory adaptations in genomic sequences...

  17. Heat transfer enhancement by pin elements

    Energy Technology Data Exchange (ETDEWEB)

    Sahiti, N.; Durst, F.; Dewan, A. [LSTM-Erlangen, Institute of Fluid Mechanics, Friedrich-Alexander-Universitaet Erlangen-Nuernberg, Cauerstrasse 4, D-91058 Erlangen (Germany)

    2005-11-01

    Heat transfer enhancement is an active and important field of engineering research since increases in the effectiveness of heat exchangers through suitable heat transfer augmentation techniques can result in considerable technical advantages and savings of costs. Considerable enhancements were demonstrated in the present work by using small cylindrical pins on surfaces of heat exchangers. A partly quantitative theoretical treatment of the proposed method is presented. It uses simple relationships for the conductive and convective heat transfer to derive an equation that shows which parameters permit the achievement of heat transfer enhancements. Experiments are reported that demonstrate the effectiveness of the results of the proposed approach. It is shown that the suggested method of heat transfer enhancements is much more effective than existing methods, since it results in an increase in heat transfer area (like fins) and also an increase in the heat transfer coefficient. (author)

  18. Inhomogeneous thermal conductivity enhances thermoelectric cooling

    Directory of Open Access Journals (Sweden)

    Tingyu Lu

    2014-12-01

    Full Text Available We theoretically investigate the enhancement of thermoelectric cooling performance in thermoelectric refrigerators made of materials with inhomogeneous thermal conductivity, beyond the usual practice of enhancing thermoelectric figure of merit (ZT of materials. The dissipation of the Joule heat in such thermoelectric refrigerators is asymmetric which can give rise to better thermoelectric cooling performance. Although the thermoelectric figure of merit and the coefficient-of-performance are slightly enhanced, both the maximum cooling power and the maximum cooling temperature difference can be enhanced significantly. This finding can be used to increase the heat absorption at the cold end. We further find that the asymmetric dissipation of Joule heat leads to thermal rectification.

  19. Does (in)formal learning enhance employability?

    NARCIS (Netherlands)

    Van der Heijden, Beate; Boon, Jo; Van der Klink, Marcel; Meijs, Ely

    2009-01-01

    Van der Heijden, B. I. J. M., Boon, J., Van der Klink, M., & Meys, E. (2008). Does (in)formal learning enhance employability? Paper presented at the AHRD Conference. February, 2008, Panama Florida, USA.

  20. Curved Gabor Filters for Fingerprint Image Enhancement

    CERN Document Server

    Gottschlich, Carsten

    2011-01-01

    Gabor filters play an important role in many application areas for the enhancement of various types of images and the extraction of Gabor features. For the purpose of enhancing curved structures in noisy images, we introduce curved Gabor filters which locally adapt their shape to the direction of flow. These curved Gabor filters enable the choice of filter parameters which increase the smoothing power without creating artifacts in the enhanced image. In this paper, curved Gabor filters are applied to the curved ridge and valley structure of low-quality fingerprint images. First, we combine two orientation field estimation methods in order to obtain a more robust estimation for very noisy images. Next, curved regions are constructed by following the respective local orientation and they are used for estimating the local ridge frequency. Lastly, curved Gabor filters are defined based on curved regions and they are applied for the enhancement of low-quality fingerprint images. Experimental results on the FVC2004...

  1. Learning in a technology enhanced world

    NARCIS (Netherlands)

    Specht, Marcus

    2010-01-01

    Specht, M. (2009). Learning in a technology enhanced world. Invited talk given at the World Conference on E-learning in Corporate, Government, Healthcare & Higher Education. October, 27, 2009, Vancouver, Canada.

  2. Learning Enhancement in Tertiary Institutions Using Mobile ...

    African Journals Online (AJOL)

    2012-12-01

    Dec 1, 2012 ... In addition to identifying some of the ways in which traditional learning has hampered ... for a world population just over 6 billion .... Page 3 ... working, hiking in the mountains, playing, ... can enhance interaction between and.

  3. Viability of Biopolymers for Enhanced Oil Recovery

    NARCIS (Netherlands)

    Sveistrup, Marte; van Mastrigt, Frank; Norrman, Jens; Picchioni, Francesco; Paso, Kristofer

    2016-01-01

    Xanthan gum and scleroglucan are assessed as environmentally friendly enhanced oil recovery (EOR) agents. Viscometric and interfacial tension measurements show that the polysaccharides exhibit favorable viscosifying performance, robust shear tolerance, electrolyte tolerance, and moderate interaction

  4. [Normal and abnormal meningeal enhancement: MRI features].

    Science.gov (United States)

    Dietemann, J L; Correia Bernardo, R; Bogorin, A; Abu Eid, M; Koob, M; Nogueira, Th; Vargas, M I; Fakhoury, W; Zöllner, G

    2005-11-01

    The authors describe normal imaging of the meninges and meningeal spaces and MR (magnetic resonance) imaging findings in tumoral and nontumoral diseases. Dural or/and pial enhancement may be related to tumoral, infectious or granulomatous diseases.

  5. Resonant metallic nanostructures for enhanced terahertz spectroscopy

    KAUST Repository

    Toma, A.

    2015-11-12

    We present our recent studies on terahertz resonant dipole nanoantennas. Exploiting the localization and enhancement capabilities of these devices, we introduce an effective method to perform terahertz spectroscopy on an extremely small number of nano-objects.

  6. Aerodynamic Efficiency Enhancements for Air Vehicles Project

    Data.gov (United States)

    National Aeronautics and Space Administration — The need for aerodynamics-based efficiency enhancements for air vehicles is presented. Concepts are presented for morphing aircraft, to enable the aircraft to...

  7. An Evaluation of Enhanced Geothermal Systems Technology

    Energy Technology Data Exchange (ETDEWEB)

    Jelacic, Allan [U.S. Dept. of Energy, Washington, DC (United States); Fortuna, Raymond [U.S. Dept. of Energy, Washington, DC (United States); LaSala, Raymond [U.S. Dept. of Energy, Washington, DC (United States); Nathwani, Jay [U.S. Dept. of Energy, Washington, DC (United States); Nix, Gerald [U.S. Dept. of Energy, Washington, DC (United States); Visser, Charles [National Renewable Energy Lab. (NREL), Golden, CO (United States); Green, Bruce [National Renewable Energy Lab. (NREL), Golden, CO (United States); Renner, Joel [Idaho National Lab. (INL), Idaho Falls, ID (United States); Blankenship, Douglas [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Kennedy, Mack [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Bruton, Carol [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)

    2008-04-01

    This 2008 document presents the results of an eight-month study by the Department of Energy (DOE) and its support staff at the national laboratories concerning the technological requirements to commercialize a new geothermal technology, Enhanced Geothermal Systems (EGS).

  8. Enhancing transdermal drug delivery with electroporation.

    Science.gov (United States)

    Wong, Tak-Wah; Ko, Shu-Fen; Hui, Sek-Wen

    2008-01-01

    The application of electroporation to enhance transdermal delivery has opened up a new possibility to introduce larger molecules such as peptide hormones and vaccines as well as minigenes and RNAi etc. through the transdermal route. Many devices have been developed to deliver the pulse electric field needed to permeate the skin. These devices include both non-puncturing surface electrodes as well as puncturing electrodes of different geometrical arrangements. The latter type uses electroporation only to increase uptake of molecules injected through the puncturing electrode or syringe. Different electroporation protocols have been developed to maximize transport, uptake and minimizing pain. Synergistic effect of chemical enhancers and physical (sonic, vibrational and thermal) treatments are used to enhance the transport. This article reviews the patents pertaining to the instrumentation as well as application protocols of transdermal delivery, uptake enhancement and interstitial fluid sampling by electroporation.

  9. ENHANCEMENT TECHNIQUES FOR DATA WAREHOUSE STAGING AREA

    OpenAIRE

    Mahmoud El-Wessimy; Hoda M. O. Mokhtar; Osman Hegazy

    2013-01-01

    Poor performance can turn a successful data warehousing project into a failure. Consequently, several attempts have been made by various researchers to deal with the problem of scheduling the ExtractTransform-Load (ETL) process. In this paper we therefore present several approaches in the context of enhancing the data warehousing Extract, Transform and loading stages. We focus on enhancing the performance of extract and transform phases by proposing two algorithms that reduce the ...

  10. Genetic enhancement, human nature, and rights.

    Science.gov (United States)

    McConnell, Terrance

    2010-08-01

    Authors such as Francis Fukuyama, the President's Council on Bioethics, and George Annas have argued that biotechnological interventions that aim to promote genetic enhancement pose a threat to human nature. This paper clarifies what conclusions these critics seek to establish, and then shows that there is no plausible account of human nature that will meet the conditions necessary to support this position. Appeals to human nature cannot establish a prohibition against the pursuit of genetic enhancement.

  11. Tunable spectral enhancement of fiber supercontinuum

    Science.gov (United States)

    Yeom, Dong-Il; Bolger, Jeremy A.; Marshall, Graham D.; Austin, Dane R.; Kuhlmey, Boris T.; Withford, Michael J.; de Sterke, C. Martijn; Eggleton, Benjamin J.

    2007-06-01

    We demonstrate tunable spectral enhancement of the supercontinuum generated in a microstructured fiber with a fiber long-period grating. The long-period grating leads to phase distortion and loss that, with subsequent high-intensity propagation in uniform fiber, evolves into an enhancement around the grating's resonant wavelengths. Wavelength tunability is achieved by varying the temperature or the ambient refractive index, and the spectral peak can be extinguished by immersing the grating in index-matching oil.

  12. Enhanced Graphene Photodetector with Fractal Metasurface

    DEFF Research Database (Denmark)

    Fan, Jieran; Wang, Di; DeVault, Clayton

    2016-01-01

    We designed and fabricated a broadband, polarization-independent photodetector by integrating graphene with a fractal Cayley tree metasurface. Our measurements show an almost uniform, tenfold enhancement in photocurrent generation due to the fractal metasurface structure.......We designed and fabricated a broadband, polarization-independent photodetector by integrating graphene with a fractal Cayley tree metasurface. Our measurements show an almost uniform, tenfold enhancement in photocurrent generation due to the fractal metasurface structure....

  13. An Efficient Algorithm for Image Enhancement

    Directory of Open Access Journals (Sweden)

    Manglesh Khandelwal

    2011-02-01

    Full Text Available In the digital image processing field enhancement and removing the noise in the image is a critical issue. We have proposed a new algorithmto enhance color Image corrupted by Gaussian noise using fuzzy logic which describes uncertain features of images with modification of median filter. . The performance of the proposed technique has been evaluated and compared to the existing mean and median filter.

  14. Enhanced optomechanical readout using optical coalescence

    DEFF Research Database (Denmark)

    Genes, Claudiu; Xuereb, André; Pupillo, Guido;

    2013-01-01

    We present a scheme to strongly enhance the readout sensitivity of the squared displacement of a mobile scatterer placed in a Fabry-Pérot cavity. We investigate the largely unexplored regime of cavity electrodynamics in which a highly reflective element positioned between the end mirrors of a sym...... in this generic “optical coalescence” phenomenon gives rise to an enhanced frequency shift of the peaks of the cavity transmission that can be exploited in optomechanics....

  15. Metal Nanostructures for Detection and Imaging Enhancements

    Science.gov (United States)

    2011-01-03

    source spectrum, is delivered into a pig adipose sample. OCT is a widely used optical imaging technique for the diagnoses of many diseases [27-29... Fahr , C. Rockstuhl, and F. Lederer, “Engineering the randomness for enhanced absorption in solar cells,” Appl. Phys. Lett. 92, 171114 (2008). 7. T...Rockstuhl, S. Fahr , and F. Lederer, “Absorption enhancement in solar cells by localized plasmon polaritons,” J. Appl. Phys. 104, 123102 (2008). 31. A

  16. Strategy to Enhance International Supply Chain Security

    Science.gov (United States)

    2007-07-01

    a strategic plan to enhance the security of the international supply chain , including protocols for the expeditious resumption of the flow of trade...following a transportation disruption or transportation security incident. The Strategy to Enhance International Supply Chain Security exists within a...extensive risk analysis specific to the risk area they cover in the supply chain . Assessments are used to identify the highest risk areas and resources

  17. Recent Progress on Plasmon-Enhanced Fluorescence

    Directory of Open Access Journals (Sweden)

    Dong Jun

    2015-12-01

    Full Text Available The optically generated collective electron density waves on metal–dielectric boundaries known as surface plasmons have been of great scientific interest since their discovery. Being electromagnetic waves on gold or silver nanoparticle’s surface, localised surface plasmons (LSP can strongly enhance the electromagnetic field. These strong electromagnetic fields near the metal surfaces have been used in various applications like surface enhanced spectroscopy (SES, plasmonic lithography, plasmonic trapping of particles, and plasmonic catalysis. Resonant coupling of LSPs to fluorophore can strongly enhance the emission intensity, the angular distribution, and the polarisation of the emitted radiation and even the speed of radiative decay, which is so-called plasmon enhanced fluorescence (PEF. As a result, more and more reports on surface-enhanced fluorescence have appeared, such as SPASER-s, plasmon assisted lasing, single molecule fluorescence measurements, surface plasmoncoupled emission (SPCE in biological sensing, optical orbit designs etc. In this review, we focus on recent advanced reports on plasmon-enhanced fluorescence (PEF. First, the mechanism of PEF and early results of enhanced fluorescence observed by metal nanostructure will be introduced. Then, the enhanced substrates, including periodical and nonperiodical nanostructure, will be discussed and the most important factor of the spacer between molecule and surface and wavelength dependence on PEF is demonstrated. Finally, the recent progress of tipenhanced fluorescence and PEF from the rare-earth doped up-conversion (UC and down-conversion (DC nanoparticles (NPs are also commented upon. This review provides an introduction to fundamentals of PEF, illustrates the current progress in the design of metallic nanostructures for efficient fluorescence signal amplification that utilises propagating and localised surface plasmons.

  18. Recent Progress on Plasmon-Enhanced Fluorescence

    Science.gov (United States)

    Dong, Jun; Zhang, Zhenglong; Zheng, Hairong; Sun, Mentao

    2015-12-01

    The optically generated collective electron density waves on metal-dielectric boundaries known as surface plasmons have been of great scientific interest since their discovery. Being electromagnetic waves on gold or silver nanoparticle's surface, localised surface plasmons (LSP) can strongly enhance the electromagnetic field. These strong electromagnetic fields near the metal surfaces have been used in various applications like surface enhanced spectroscopy (SES), plasmonic lithography, plasmonic trapping of particles, and plasmonic catalysis. Resonant coupling of LSPs to fluorophore can strongly enhance the emission intensity, the angular distribution, and the polarisation of the emitted radiation and even the speed of radiative decay, which is so-called plasmon enhanced fluorescence (PEF). As a result, more and more reports on surface-enhanced fluorescence have appeared, such as SPASER-s, plasmon assisted lasing, single molecule fluorescence measurements, surface plasmoncoupled emission (SPCE) in biological sensing, optical orbit designs etc. In this review, we focus on recent advanced reports on plasmon-enhanced fluorescence (PEF). First, the mechanism of PEF and early results of enhanced fluorescence observed by metal nanostructure will be introduced. Then, the enhanced substrates, including periodical and nonperiodical nanostructure, will be discussed and the most important factor of the spacer between molecule and surface and wavelength dependence on PEF is demonstrated. Finally, the recent progress of tipenhanced fluorescence and PEF from the rare-earth doped up-conversion (UC) and down-conversion (DC) nanoparticles (NPs) are also commented upon. This review provides an introduction to fundamentals of PEF, illustrates the current progress in the design of metallic nanostructures for efficient fluorescence signal amplification that utilises propagating and localised surface plasmons.

  19. Citalopram enhances cocaine's subjective effects in rats

    OpenAIRE

    Soto, Paul L.; Hiranita, Takato; Katz, Jonathan L.

    2009-01-01

    Serotonin-selective reuptake inhibitors (SSRIs) have been shown to enhance the locomotor stimulatory, discriminative-stimulus, and convulsive effects of cocaine in rodents. A pharmacokinetic mechanism for the interaction is supported by increases in the brain levels of cocaine by fluoxetine treatment. Furthermore, the locomotor-stimulant effects of cocaine in rodents are enhanced by fluoxetine and fluvoxamine, SSRIs known to inhibit cocaine-metabolizing cytochrome P450 enzymes, whereas citalo...

  20. CO2 enhanced oil recovery economics

    Energy Technology Data Exchange (ETDEWEB)

    Bloomquist, C.W.

    1983-01-01

    Realistic estimates of potential enhanced oil recovery (EOR) reserve additions range from 15 to 50 billion bbl. Oil price, technical advancements, and taxation will strongly influence how much of this potential can be realized. EOR can be implemented on a large scale in the near term, and can contribute significantly to domestic oil production by the late 1980s. The contribution of CO2 injection recovery processes to this enhancement of oil reserves is examined with regard to economics and technology.

  1. Enhancing Biological Wastewater Treatment with Chitosan

    Institute of Scientific and Technical Information of China (English)

    陈亮; 陈东辉; 朱珺

    2003-01-01

    Chitin and chitosan have been applied to biological wastewater treatment.From a number of parallel comparison experiments,it can be concluded that the application of chitin and chitosan can both enhance the biological treatment,besides which chitosan is more efficient than chitin.The study on the enhancement mechanism reveals the difference between the two additives:chitosan improves the sludge structure and settlibility,while chitin acts as a kind of carrier for microorganism in the biological treatment system.

  2. Salmon River Habitat Enhancement. 1990 Annual Report

    Energy Technology Data Exchange (ETDEWEB)

    Rowe, Mike

    1991-12-01

    The annual report contains three individual subproject sections detailing tribal fisheries work completed during the summer and fall of 1990. Subproject I contains summaries of evaluation/monitoring efforts associated with the Bear Valley Creek, Idaho enhancement project. Subproject II contains an evaluation of the Yankee Fork of the Salmon River habitat enhancement project. Subproject III concerns the East Fork of the Salmon River, Idaho.

  3. Surface-enhanced Raman scattering of Ethyl carbamate adsorbed on Ag20 cluster: Enhancement mechanism

    Science.gov (United States)

    Du, Junmei; Wang, Hongyan; Wang, Hui; Chen, Yuanzheng; Guo, Chunsheng; Gan, Liyong; Du, Muying

    2017-03-01

    The normal and surface-enhanced Raman scattering of EC are studied by using the M06-2X functional. Different contributions to Raman enhancements of EC adsorbed on Ag20 cluster are analyzed in detail to explore the enhancement mechanism. The adsorption of EC on Ag20 cluster involves the static chemical enhancement with enhancements factor (EF) of 10 by forming a new EC-Ag20 complex. The charge-transfer enhancement with EF of 104 is found when a 352 nm wavelength, corresponding to the absorption maximum of EC-Ag20 complex, is taken as an incident light. The electromagnetic enhancement EF of 3.6 × 106 due to the localized surface plasmon resonance (LSPR) of Ag nanosphere at the same excitation wavelength are acquired by the discrete dipole approximation (DDA) method. The combined effect of the chemical and electromagnetic enhancement results in the total relative enhancements factor up to 3.6 × 1010. The enhancement mechanisms are successfully explained by the combination of ab initio calculation and discrete dipole appropriation method.

  4. Enhancer activity-based identification of functional enhancers using zebrafish embryos.

    Science.gov (United States)

    Taminato, Tomohito; Yokota, Daisuke; Araki, Soh; Ovara, Hiroki; Yamasu, Kyo; Kawamura, Akinori

    2016-08-01

    Chromatin immunoprecipitation (ChIP) against enhancer-associated marks with massive sequencing is a powerful approach to identify genome-wide distributions of putative enhancers. However, functional in vivo analysis is required to elucidate the activities of predicted enhancers. Using zebrafish embryos, we established a ChIP-Injection method that enables identification of functional enhancers based on their enhancer activities in embryos. Each reporter gene possessing the enhancer-associated genomic region enriched by ChIP was injected into zebrafish embryos to analyze the activity of putative enhancers. By using the ChIP-Injection, we identified 32 distinct putative enhancers that drove specific expression. Additionally, we generated transgenic lines that exhibit distributions of the EGFP signal as was observed in the screening. Furthermore, the expression pattern driven by the identified somite-specific enhancer resembled that of the gene acta2. The results indicate that ChIP-Injection provides an efficient approach for identification of active enhancers in a potentially wide variety of developmental tissues and stages.

  5. Enhanced MRI in patients with facial palsy; Study of time-related enhancement

    Energy Technology Data Exchange (ETDEWEB)

    Yanagida, Masahiro; Kato, Tsutomu; Ushiro, Koichi; Kitajiri, Masanori; Yamashita, Toshio; Kumazawa, Tadami; Tanaka, Yoshimasa (Kansai Medical School, Moriguchi, Osaka (Japan))

    1991-03-01

    We performed Gd-DTPA-enhanced magnetic resonance imaging (MRI) examinations at several stages in 40 patients with peripheral facial nerve palsy (Bell's palsy and Ramsay-Hunt syndrome). In 38 of the 40 patients, one and more enhanced region could be seen in certain portion of the facial nerve in the temporal bone on the affected side, whereas no enhanced regions were seen on the intact side. Correlations between the timing of the MRI examination and the location of the enhanced regions were analysed. In all 6 patients examined by MRI within 5 days after the onset of facial nerve palsy, enhanced regions were present in the meatal portion. In 3 of the 8 patients (38%) examined by MRI 6 to 10 days after the onset of facial palsy, enhanced areas were seen in both the meatal and labyrinthine portions. In 8 of the 9 patients (89%) tested 11 to 20 days after the onset of palsy, the vertical portion was enhanced. In the 12 patients examined by MRI 21 to 40 days after the onset of facial nerve palsy, the meatal portion was not enhanced while the labyrinthine portion, the horizontal portion and the vertical portion were enhanced in 5 (42%), 8 (67%) and 11 (92%), respectively. Enhancement in the vertical portion was observed in all 5 patients examined more than 41 days after the onset of facial palsy. These results suggest that the central portion of the facial nerve in the temporal bone tends to be enhanced in the early stage of facial nerve palsy, while the peripheral portion is enhanced in the late stage. These changes of Gd-DTPA enhanced regions in the facial nerve may suggest dromic degeneration of the facial nerve in peripheral facial nerve palsy. (author).

  6. Metal-enhanced fluorescence of carbon nanotubes.

    Science.gov (United States)

    Hong, Guosong; Tabakman, Scott M; Welsher, Kevin; Wang, Hailiang; Wang, Xinran; Dai, Hongjie

    2010-11-17

    The photoluminescence (PL) quantum yield of single-walled carbon nanotubes (SWNTs) is relatively low, with various quenching effects by metallic species reported in the literature. Here, we report the first case of metal enhanced fluorescence (MEF) of surfactant-coated carbon nanotubes on nanostructured gold substrates. The photoluminescence quantum yield of SWNTs is observed to be enhanced more than 10-fold. The dependence of fluorescence enhancement on metal-nanotube distance and on the surface plasmon resonance (SPR) of the gold substrate for various SWNT chiralities is measured to reveal the mechanism of enhancement. Surfactant-coated SWNTs in direct contact with metal exhibit strong MEF without quenching, suggesting a small quenching distance for SWNTs on the order of the van der Waals distance, beyond which the intrinsically fast nonradiative decay rate in nanotubes is little enhanced by metal. The metal enhanced fluorescence of SWNTs is attributed to radiative lifetime shortening through resonance coupling of SWNT emission to the reradiating dipolar plasmonic modes in the metal.

  7. [Doping in sport and enhancement medicine].

    Science.gov (United States)

    Missa, Jean-Noël

    2011-01-01

    The reason that gives doping in sport a deeper philosophical and ethical dimension is the emergence of a new medical paradigm: enhancement medicine. The question of enhancing performance in sport has become part of a broader societal debate on human enhancement. The gradual blurriness of the boarders between therapeutic medicine and enhancement medicine constitutes the most spectacular and the most troublesome form of these modifications. In the contemporary biomedicine, the new medicines and technologies can be used not only to cure the patients but also to enhance human capacities. This evolution represents a paradigmatic change in the medical practice: it is not the mere restoration of health which is expected anymore, nor the promotion of health. What is required is the improvement of performance and the perfectibility of the human being, including in the field of sport. Competitive sport could become the main laboratory of enhancement medicine. The intersection of science and sport raises fundamental philosophical, ethical and policy issues that cannot be answered easily. The prohibition and the war on doping is not the only solution.

  8. Central cholinesterase inhibition enhances glutamatergic synaptic transmission.

    Science.gov (United States)

    Kozhemyakin, Maxim; Rajasekaran, Karthik; Kapur, Jaideep

    2010-04-01

    Central cholinergic overstimulation results in prolonged seizures of status epilepticus in humans and experimental animals. Cellular mechanisms of underlying seizures caused by cholinergic stimulation remain uncertain, but enhanced glutamatergic transmission is a potential mechanism. Paraoxon, an organophosphate cholinesterase inhibitor, enhanced glutamatergic transmission on hippocampal granule cells synapses by increasing the frequency and amplitude of spontaneous excitatory postsynaptic currents (sEPSCs) in a concentration-dependent fashion. The amplitude of mEPSCs was not increased, which suggested the possibility of enhanced action potential-dependent release. Analysis of EPSCs evoked by minimal stimulation revealed reduced failures and increased amplitude of evoked responses. The ratio of amplitudes of EPSCs evoked by paired stimuli was also altered. The effect of paraoxon on glutamatergic transmission was blocked by the muscarinic antagonist atropine and partially mimicked by carbachol. The nicotinic receptor antagonist α -bungarotoxin did not block the effects of paraoxon; however, nicotine enhanced glutamatergic transmission. These studies suggested that cholinergic overstimulation enhances glutamatergic transmission by enhancing neurotransmitter release from presynaptic terminals.

  9. Localized basal meningeal enhancement in tuberculous meningitis

    Energy Technology Data Exchange (ETDEWEB)

    Theron, Salomine; Andronikou, Savvas; Grobbelaar, Marie; Steyn, Freda; Mapukata, Ayanda; Plessis, Jaco du [University of Stellenbosch, Department of Radiology, Tygerberg Hospital, P.O. BOX 19063, Tygerberg (South Africa)

    2006-11-15

    Focal basal meningeal enhancement may produce a confusing CT picture in children with suspected tuberculous meningitis (TBM). To demonstrate the incidence, distribution and appearance of localized basal meningeal enhancement in children with TBM. CT scans of patients with definite (culture proven) and probable (CSF suggestive) TBM were retrospectively evaluated by two observers. Localized basal enhancement was documented as involving: unilateral cistern of the lateral fossa (CLF), unilateral sylvian fissure, unilateral CLF and sylvian fissure in combination, unilateral CLF and sylvian fissure with ipsi- or contralateral ambient cistern and isolated quadrigeminal plate cistern. The study included 130 patients with TBM (aged 2 months to 13 years 9 months). Focal basal enhancement was seen in 11 patients (8.5%). The sylvian fissure was involved most commonly, followed by the lateral fossa cistern. The ambient cistern was involved in three patients and the quadrigeminal plate cistern in one. Focal areas of enhancement corresponded to the areas of infarction in every patient. Focal basal meningeal enhancement is common (8.5%) in paediatric TBM. This must be kept in mind when evaluating CT scans in children presenting with focal neurological findings, seizures or meningism in communities where TBM is endemic. (orig.)

  10. Contrast Enhanced US in the Abdomen

    Energy Technology Data Exchange (ETDEWEB)

    Chung, Yong Eun; Kim, Ki Whang [Dept. of Radiology, Research Institute of Radiological Science, Severance Hospital, Yonsei University College of Medicine, Seoul (Korea, Republic of)

    2012-08-15

    Contrast enhanced ultrasound, which was introduced in 1996, has been widely used in Europe and Eastern Asia. Ultrasound contrast agent can be classified as first generation and second generation, depending on the gas within the microbubble. With the first generation contrast agent, the high MI technique was used, and only intermittent scanning was possible due to destruction of the microbubble during scanning. Use of the second generation contrast agent with the low MI technique makes continuous scanning possible. Contrast enhanced US can be used in detection and differentiation of focal liver lesions. It is also helpful for monitoring of radiofrequency ablation and for targeting of US guided biopsy. Currently, because morphologic criteria alone may not reflect the response of the tumor to treatment, new criteria are needed for treatment evaluation after administration of anti-angiogenic agents. Contrast enhanced US could provide quantitative markers for evaluation of the response to treatment via use of dynamic contrast enhanced US. Due to cost-effectiveness, contrast enhanced US is not yet widely used in Korea; however, considering recent issues regarding contrast agent related adverse reaction, such as contrast induced nephropathy and nephrogenic systemic fibrosis, and radiation exposure, contrast enhanced US might be more widely used in Korea, as an alternative imaging modality in the future.

  11. Is human enhancement also a personal matter?

    Science.gov (United States)

    Menuz, Vincent; Hurlimann, Thierry; Godard, Béatrice

    2013-03-01

    Emerging technologies are increasingly used in an attempt to "enhance the human body and/or mind" beyond the contemporary standards that characterize human beings. Yet, such standards are deeply controversial and it is not an easy task to determine whether the application of a given technology to an individual and its outcome can be defined as a human enhancement or not. Despite much debate on its potential or actual ethical and social impacts, human enhancement is not subject to any consensual definition. This paper proposes a timely and much needed examination of the various definitions found in the literature. We classify these definitions into four main categories: the implicit approach, the therapy-enhancement distinction, the improvement of general human capacities and the increase of well-being. After commenting on these different approaches and their limitations, we propose a definition of human enhancement that focuses on individual perceptions. While acknowledging that a definition that mainly depends on personal and subjective individual perceptions raises many challenges, we suggest that a comprehensive approach to define human enhancement could constitute a useful premise to appropriately address the complexity of the ethical and social issues it generates.

  12. Enhancement of Cellulose Degradation by Cattle Saliva.

    Science.gov (United States)

    Seki, Yasutaka; Kikuchi, Yukiko; Kimura, Yoshihiro; Yoshimoto, Ryo; Takahashi, Masatoshi; Aburai, Kenichi; Kanai, Yoshihiro; Ruike, Tatsushi; Iwabata, Kazuki; Sugawara, Fumio; Sakai, Hideki; Abe, Masahiko; Sakaguchi, Kengo

    2015-01-01

    Saccharification of cellulose is a promising technique for producing alternative source of energy. However, the efficiency of conversion of cellulose into soluble sugar using any currently available methodology is too low for industrial application. Many additives, such as surfactants, have been shown to enhance the efficiency of cellulose-to-sugar conversion. In this study, we have examined first whether cattle saliva, as an additive, would enhance the cellulase-catalyzed hydrolysis of cellulose, and subsequently elucidated the mechanism by which cattle saliva enhanced this conversion. Although cattle saliva, by itself, did not degrade cellulose, it enhanced the cellulase-catalyzed degradation of cellulose. Thus, the amount of reducing sugar produced increased approximately 2.9-fold by the addition of cattle saliva. We also found that non-enzymatic proteins, which were present in cattle saliva, were responsible for causing the enhancement effect. Third, the mechanism of cattle saliva mediated enhancement of cellulase activity was probably similar to that of the canonical surfactants. Cattle saliva is available in large amounts easily and cheaply, and it can be used without further purification. Thus, cattle saliva could be a promising additive for efficient saccharification of cellulose on an industrial scale.

  13. Method for enhancing amidohydrolase activity of fatty acid amide hydrolase

    Energy Technology Data Exchange (ETDEWEB)

    John, George; Nagarajan, Subbiah; Chapman, Kent; Faure, Lionel; Koulen, Peter

    2016-10-25

    A method for enhancing amidohydrolase activity of Fatty Acid Amide Hydrolase (FAAH) is disclosed. The method comprising administering a phenoxyacylethanolamide that causes the enhanced activity. The enhanced activity can have numerous effects on biological organisms including, for example, enhancing the growth of certain seedlings. The subject matter disclosed herein relates to enhancers of amidohydrolase activity.

  14. Postnatal Human Genetic Enhancement – A Consideration of Children’s Right to Be Genetically Enhanced

    OpenAIRE

    Tamir, Sivan

    2016-01-01

    This paper considers children’s rights with respect to genetic enhancement (GE). It is focused on the futuristic prospect of postnatal GE, namely, genetic modifications, in vivo, of actual existing individuals. More specifically, the paper examines whether, in a future reality where pre- and postnatal human GE is safely and prevalently practiced, a child would have a right to be genetically enhanced by her parents or guardians, as well as the right not to be genetically enhanced. It is in fac...

  15. Enhanced thermophysical properties via PAO superstructure

    Science.gov (United States)

    Pournorouz, Zahra; Mostafavi, Amirhossein; Pinto, Aditya; Bokka, Apparao; Jeon, Junha; Shin, Donghyun

    2017-01-01

    For the last few years, molten salt nanomaterials have attracted many scientists for their enhanced specific heat by doping a minute concentration of nanoparticles (up to 1% by weight). Likewise, enhancing the specific heat of liquid media is important in many aspects of engineering such as engine oil, coolant, and lubricant. However, such enhancement in specific heat was only observed for molten salts, yet other engineering fluids such as water, ethylene glycol, and oil have shown a decrease of specific heat with doped nanoparticles. Recent studies have shown that the observed specific heat enhancement resulted from unique nanostructures that were formed by molten salt molecules when interacting with nanoparticles. Thus, such enhancement in specific heat is only possible for molten salts because other fluids may not naturally form such nanostructures. In this study, we hypothesized such nanostructures can be mimicked through in situ formation of fabricated nano-additives, which are putative nanoparticles coated with useful organic materials (e.g., polar-group-ended organic molecules) leading to superstructures, and thus can be directly used for other engineering fluids. We first applied this approach to polyalphaolefin (PAO). A differential scanning calorimeter (DSC), a rheometer, and a customized setup were employed to characterize the heat capacity, viscosity, and thermal conductivity of PAO and PAO with fabricated nano-additives. Results showed 44.5% enhanced heat capacity and 19.8 and 22.98% enhancement for thermal conductivity and viscosity, respectively, by an addition of only 2% of fabricated nanostructures in comparison with pure PAO. Moreover, a partial melting of the polar-group-ended organic molecules was observed in the first thermal cycle and the peak disappeared in the following cycles. This indicates that the in situ formation of fabricated nano-additives spontaneously occurs in the thermal cycle to form nanostructures. Figure of merit analyses have

  16. Contrast-enhanced ultrasound study of primary hepatic angiosarcoma: A pitfall of non-enhancement

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Liang, E-mail: liangw_1983@yahoo.com.cn [Department of Ultrasound, Chinese Academy of Medical Sciences and Peking Union Medical College Hospital, 1 Shuaifuyuan Wangfujing, Beijing 100730 (China); Lv, Ke, E-mail: lvke@163.com [Department of Ultrasound, Chinese Academy of Medical Sciences and Peking Union Medical College Hospital, 1 Shuaifuyuan Wangfujing, Beijing 100730 (China); Chang, Xiao-Yan, E-mail: changxiaoyan@hotmail.com [Department of Ultrasound, Chinese Academy of Medical Sciences and Peking Union Medical College Hospital, 1 Shuaifuyuan Wangfujing, Beijing 100730 (China); Xia, Yu, E-mail: yuxiapumch@yahoo.com.cn [Department of Ultrasound, Chinese Academy of Medical Sciences and Peking Union Medical College Hospital, 1 Shuaifuyuan Wangfujing, Beijing 100730 (China); Yang, Zhi-Ying, E-mail: yangzhy@yahoo.com.cn [Department of Ultrasound, Chinese Academy of Medical Sciences and Peking Union Medical College Hospital, 1 Shuaifuyuan Wangfujing, Beijing 100730 (China); Jiang, Yu-Xin, E-mail: jiangyx@pumch.ac.cn [Department of Ultrasound, Chinese Academy of Medical Sciences and Peking Union Medical College Hospital, 1 Shuaifuyuan Wangfujing, Beijing 100730 (China); Dai, Qing, E-mail: qingdai_2000@yahoo.com [Department of Ultrasound, Chinese Academy of Medical Sciences and Peking Union Medical College Hospital, 1 Shuaifuyuan Wangfujing, Beijing 100730 (China); Tan, Li, E-mail: tanlixg@163.com [Department of Ultrasound, Chinese Academy of Medical Sciences and Peking Union Medical College Hospital, 1 Shuaifuyuan Wangfujing, Beijing 100730 (China); Li, Jian-Chu, E-mail: jianchu.li@163.com [Department of Ultrasound, Chinese Academy of Medical Sciences and Peking Union Medical College Hospital, 1 Shuaifuyuan Wangfujing, Beijing 100730 (China)

    2012-09-15

    Highlights: ► The contrast-enhanced ultrasound (CEUS) characteristics of primary hepatic angiosarcoma (PHA) in three patients were retrospectively analyzed. ► PHA appeared similar peripheral enhancement pattern in our series. ► Non-necrotic tumor tissue of PHA unexpectedly demonstrated non-enhancement on CEUS. ► It may be associated with the very low velocity of blood flow in the central region of tumors. ► This interesting finding warrants further investigations, particularly on intratumoral hemodynamics. -- Abstract: Objective: To investigate the contrast-enhanced ultrasound (CEUS) characteristics of primary hepatic angiosarcoma (PHA). Methods: The sonographic findings and CEUS images of PHA in three patients were retrospectively analyzed. Results: In our study, 3 cases of PHA (2 multiple nodules and 1 solitary mass) showed similar enhancement pattern on CEUS, characterized by remarkable central non-enhancement and peripheral irregular enhancement in the arterial and portal phase, and complete wash-out in the late phase. Furthermore, we unexpectedly found that abundant neoplastic tissues were present in the central area of non-enhancement on pathological evaluation. Based on literature review, we supposed that the unusual finding may be associated with the very low velocity of blood flow in the central region of tumors. Conclusion: CEUS could well depict PHA with some common features, which may provide valuable clues in diagnosis of this rare disease. And non-necrotic tumor tissue of PHA could also demonstrate non-enhancement on CEUS, which warrant further investigations.

  17. A saturation hypothesis to explain both enhanced and impaired learning with enhanced plasticity

    Science.gov (United States)

    Nguyen-Vu, TD Barbara; Zhao, Grace Q; Lahiri, Subhaneil; Kimpo, Rhea R; Lee, Hanmi; Ganguli, Surya; Shatz, Carla J; Raymond, Jennifer L

    2017-01-01

    Across many studies, animals with enhanced synaptic plasticity exhibit either enhanced or impaired learning, raising a conceptual puzzle: how enhanced plasticity can yield opposite learning outcomes? Here, we show that the recent history of experience can determine whether mice with enhanced plasticity exhibit enhanced or impaired learning in response to the same training. Mice with enhanced cerebellar LTD, due to double knockout (DKO) of MHCI H2-Kb/H2-Db (KbDb−/−), exhibited oculomotor learning deficits. However, the same mice exhibited enhanced learning after appropriate pre-training. Theoretical analysis revealed that synapses with history-dependent learning rules could recapitulate the data, and suggested that saturation may be a key factor limiting the ability of enhanced plasticity to enhance learning. Optogenetic stimulation designed to saturate LTD produced the same impairment in WT as observed in DKO mice. Overall, our results suggest that the recent history of activity and the threshold for synaptic plasticity conspire to effect divergent learning outcomes. DOI: http://dx.doi.org/10.7554/eLife.20147.001 PMID:28234229

  18. Signal enhancement of surface enhanced Raman scattering and surface enhanced resonance Raman scattering using in situ colloidal synthesis in microfluidics.

    Science.gov (United States)

    Wilson, Rab; Bowden, Stephen A; Parnell, John; Cooper, Jonathan M

    2010-03-01

    We demonstrate the enhanced analytical sensitivity of both surface enhanced Raman scattering (SERS) and surface enhanced resonance Raman scattering (SERRS) responses, resulting from the in situ synthesis of silver colloid in a microfluidic flow structure, where both mixing and optical interrogation were integrated on-chip. The chip-based sensor was characterized with a model Raman active label, rhodamine-6G (R6G), and had a limit of detection (LOD) of ca. 50 fM (equivalent to single molecule detection). The device was also used for the determination of the natural pigment, scytonemin, from cyanobacteria (as an analogue for extraterrestrial life existing in extreme environments). The observed LOD of approximately 10 pM (ca. microfluidic system than those measured using the same experimental parameters, with colloid synthesized off-chip, under quiescent conditions.

  19. MRI findings of Guillain-Barre syndrome

    Energy Technology Data Exchange (ETDEWEB)

    Park, Won Kyu; Lee, Hwa Jin; Byun, Woo Mok [Yeungnam Univ. College of Medicine, Taegu (Korea, Republic of)

    1997-04-01

    To evaluate MRI findings of Guillain-Barre syndrome. In six patients with Guillain-Barre syndrome diagnosed by clinical, cerebrospinal fluid and electrophysiologic findings, a retrospective review of MR findings was conducted. Follow-up MRI scans were carried out in two patients showing minimal clinical improvement. Marked or moderate enhancement of thickened nerve roots was seen in all cases on gadopentetate dimeglumine enhanced axial T1-weighted images. Two patterns were seen; one was even enhancement of both anterior and posterior nerve roots (n=1) and the other was enhancement of anterior nerve roots only (n=5). Enhancement and thickness of nerve roots was seen to have slightly decreased on MRI follow-up at 32 and 50 days; clinical and electrophysiologic examination showed minimal improvement. Although MRI findings of nerve root enhancement are nonspecific and can be seen in neoplastic and other inflammatory diseases, the enhancement of thickened anterior nerve roots within the cal sac suggests Guillain-Barre syndrome.

  20. Optical Antenna Enhanced Spontaneous Emission in Semiconductors

    Science.gov (United States)

    Messer, Kevin James

    Optical antennas can be used to dramatically increase the rate that semiconductors spontaneously emit photons. While traditional LEDs are limited in bandwidth due to the "slow" rate of spontaneous emission, antenna-enhanced LEDs have the potential to be a fast, efficient, nanoscale light emitter. Traditionally, lasers have dominated LEDs as the emitter in optical interconnects due to a 200x speed advantage of stimulated emission over spontaneous emission. This paradigm may be reversed by coupling LEDs to optical antennas. In fact, antenna enhanced spontaneous emission can be faster than the fastest stimulated emission. Spontaneous emission originates from dipole fluctuations within the emitting material. The size of these fluctuations is much less than the wavelength of light emission, which leads to slow spontaneous emission. Coupling the material to an optical antenna corrects the size mismatch and improves the rate of radiation. An optical antenna circuit model is developed to predict the degree to which spontaneous emission can be enhanced. The circuit model presented in this dissertation shows that enhancement over 1000x is possible while still maintaining greater than 50% efficiency. The circuit model provides insight how to design optical antennas for coupling to dipole sources, for maximum enhancement, and for high efficiency. A method for incorporating the anomalous skin effect, often overlooked in metal optics, is provided. While FDTD/FEM simulations cannot include this effect due to its nonlocal nature, its impact can be examined through the use of the optical antenna circuit model. Analysis of the tradeoff between achieving large spontaneous emission enhancement and maintaining high efficiency leads to an ideal antenna feedgap size of 10nm. Experimental demonstration of spontaneous emission enhancement from InP coupled to an arch-dipole antenna is presented. Photoluminescence measurements show light emission from antenna-coupled InP over bare InP ridges

  1. Bryostatin enhancement of memory in Hermissenda.

    Science.gov (United States)

    Kuzirian, A M; Epstein, H T; Gagliardi, C J; Nelson, T J; Sakakibara, M; Taylor, C; Scioletti, A B; Alkon, D L

    2006-06-01

    Bryostatin, a potent agonist of protein kinase C (PKC), when administered to Hermissenda was found to affect acquisition of an associative learning paradigm. Low bryostatin concentrations (0.1 to 0.5 ng/ml) enhanced memory acquisition, while concentrations higher than 1.0 ng/ml down-regulated the pathway and no recall of the associative training was exhibited. The extent of enhancement depended upon the conditioning regime used and the memory stage normally fostered by that regime. The effects of two training events (TEs) with paired conditioned and unconditioned stimuli, which standardly evoked only short-term memory (STM) lasting 7 min, were--when bryostatin was added concurrently--enhanced to a long-term memory (LTM) that lasted about 20 h. The effects of both 4- and 6-paired TEs (which by themselves did not generate LTM), were also enhanced by bryostatin to induce a consolidated memory (CM) that lasted at least 5 days. The standard positive 9-TE regime typically produced a CM lasting at least 6 days. Low concentrations of bryostatin (bryostatin concentrations higher than 1.0 ng/ml exhibited no behavioral learning. Sharp-electrode intracellular recordings of type-B photoreceptors in the eyes from animals conditioned in vivo with bryostatin revealed changes in input resistance and an enhanced long-lasting depolarization (LLD) in response to light. Likewise, quantitative immunocytochemical measurements using an antibody specific for the PKC-activated Ca2+/GTP-binding protein calexcitin showed enhanced antibody labeling with bryostatin. Animals exposed to the PKC inhibitor bisindolylmaleimide-XI (Ro-32-0432) administered by immersion prior to 9-TE conditioning showed no training-induced changes with or without bryostatin exposure. However, if animals received bryostatin before Ro-32, the enhanced acquisition and demonstrated recall still occurred. Therefore, pathways responsible for the enhancement effects induced by bryostatin were putatively mediated by PKC

  2. The Geometry of Enhancement in Multiple Regression.

    Science.gov (United States)

    Waller, Niels G

    2011-10-01

    In linear multiple regression, "enhancement" is said to occur when R (2)=b'r>r'r, where b is a p×1 vector of standardized regression coefficients and r is a p×1 vector of correlations between a criterion y and a set of standardized regressors, x. When p=1 then b≡r and enhancement cannot occur. When p=2, for all full-rank R xx≠I, R xx=E[xx']=V Λ V' (where V Λ V' denotes the eigen decomposition of R xx; λ 1>λ 2), the set [Formula: see text] contains four vectors; the set [Formula: see text]; [Formula: see text] contains an infinite number of vectors. When p≥3 (and λ 1>λ 2>⋯>λ p ), both sets contain an uncountably infinite number of vectors. Geometrical arguments demonstrate that B 1 occurs at the intersection of two hyper-ellipsoids in ℝ (p) . Equations are provided for populating the sets B 1 and B 2 and for demonstrating that maximum enhancement occurs when b is collinear with the eigenvector that is associated with λ p (the smallest eigenvalue of the predictor correlation matrix). These equations are used to illustrate the logic and the underlying geometry of enhancement in population, multiple-regression models. R code for simulating population regression models that exhibit enhancement of any degree and any number of predictors is included in Appendices A and B.

  3. Nanoantenna-Enhanced Infrared Spectroscopic Chemical Imaging.

    Science.gov (United States)

    Kühner, Lucca; Hentschel, Mario; Zschieschang, Ute; Klauk, Hagen; Vogt, Jochen; Huck, Christian; Giessen, Harald; Neubrech, Frank

    2017-05-26

    Spectroscopic infrared chemical imaging is ideally suited for label-free and spatially resolved characterization of molecular species, but often suffers from low infrared absorption cross sections. Here, we overcome this limitation by utilizing confined electromagnetic near-fields of resonantly excited plasmonic nanoantennas, which enhance the molecular absorption by orders of magnitude. In the experiments, we evaporate microstructured chemical patterns of C60 and pentacene with nanometer thickness on top of homogeneous arrays of tailored nanoantennas. Broadband mid-infrared spectra containing plasmonic and vibrational information were acquired with diffraction-limited resolution using a two-dimensional focal plane array detector. Evaluating the enhanced infrared absorption at the respective frequencies, spatially resolved chemical images were obtained. In these chemical images, the microstructured chemical patterns are only visible if nanoantennas are used. This confirms the superior performance of our approach over conventional spectroscopic infrared imaging. In addition to the improved sensitivity, our technique provides chemical selectivity, which would not be available with plasmonic imaging that is based on refractive index sensing. To extend the accessible spectral bandwidth of nanoantenna-enhanced spectroscopic imaging, we employed nanostructures with dual-band resonances, providing broadband plasmonic enhancement and sensitivity. Our results demonstrate the potential of nanoantenna-enhanced spectroscopic infrared chemical imaging for spatially resolved characterization of organic layers with thicknesses of several nanometers. This is of potential interest for medical applications which are currently hampered by state-of-art infrared techniques, e.g., for distinguishing cancerous from healthy tissues.

  4. LSD enhances the emotional response to music.

    Science.gov (United States)

    Kaelen, M; Barrett, F S; Roseman, L; Lorenz, R; Family, N; Bolstridge, M; Curran, H V; Feilding, A; Nutt, D J; Carhart-Harris, R L

    2015-10-01

    There is renewed interest in the therapeutic potential of psychedelic drugs such as lysergic acid diethylamide (LSD). LSD was used extensively in the 1950s and 1960s as an adjunct in psychotherapy, reportedly enhancing emotionality. Music is an effective tool to evoke and study emotion and is considered an important element in psychedelic-assisted psychotherapy; however, the hypothesis that psychedelics enhance the emotional response to music has yet to be investigated in a modern placebo-controlled study. The present study sought to test the hypothesis that music-evoked emotions are enhanced under LSD. Ten healthy volunteers listened to five different tracks of instrumental music during each of two study days, a placebo day followed by an LSD day, separated by 5-7 days. Subjective ratings were completed after each music track and included a visual analogue scale (VAS) and the nine-item Geneva Emotional Music Scale (GEMS-9). Results demonstrated that the emotional response to music is enhanced by LSD, especially the emotions "wonder", "transcendence", "power" and "tenderness". These findings reinforce the long-held assumption that psychedelics enhance music-evoked emotion, and provide tentative and indirect support for the notion that this effect can be harnessed in the context of psychedelic-assisted psychotherapy. Further research is required to test this link directly.

  5. Technologies and countermeasures for gas recovery enhancement

    Directory of Open Access Journals (Sweden)

    Guo Ping

    2014-10-01

    Full Text Available Since 2000, China has been ranked as one of the top countries in gas production. Nevertheless, the domestic gas production can hardly satisfy the need of national economic development. Besides, an increasing number of gas fields have come to the middle or late development stages, and most gas reservoirs have low recovery efficiency due to the low permeability and water drive nature. Therefore, gas recovery enhancement has become an urgent issue. At present, the oil recovery enhancement is well defined, and there are methods describing the remaining oil and a complete set of mature EOR (enhanced oil recovery technologies. However, the definition and description of EGR (enhanced gas recovery are still undermined, and the description method for the distribution of residual gas and EGR technologies are almost unavailable. In view of this, by reviewing a wealth of related literatures, we defined EGR and also described the remaining gas distribution based on the remaining gas abundance. In addition, collecting three typical types (low-permeability, condensate and edge/bottom water of major gas reservoirs developed both at home and abroad, we summarized the geological and development characteristics, and found out the obstructions in the development. In response, we concluded and analyzed the relevant technologies and methods for enhancing the gas recovery of such reservoirs, and proposed the suggestions about EGR technology development, which provides a significant reference and popularization basis for EGR measures in fields.

  6. Non Pharmacological Cognitive Enhancers - Current Perspectives.

    Science.gov (United States)

    Sachdeva, Ankur; Kumar, Kuldip; Anand, Kuljeet Singh

    2015-07-01

    Cognition refers to the mental processes involved in thinking, knowing, remembering, judging, and problem solving. Cognitive dysfunctions are an integral part of neuropsychiatric disorders as well as in healthy ageing. Cognitive Enhancers are molecules that help improve aspects of cognition like memory, intelligence, motivation, attention and concentration. Recently, Non Pharmacological Cognitive Enhancers have gained popularity as effective and safe alternative to various established drugs. Many of these Non Pharmacological Cognitive Enhancers seem to be more efficacious compared to currently available Pharmacological Cognitive Enhancers. This review describes and summarizes evidence on various Non Pharmacological Cognitive Enhancers such as physical exercise, sleep, meditation and yoga, spirituality, nutrients, computer training, brain stimulation, and music. We also discuss their role in ageing and different neuro-psychiatric disorders, and current status of Cochrane database recommendations. We searched the Pubmed database for the articles and reviews having the terms 'non pharmacological and cognitive' in the title, published from 2000 till 2014. A total of 11 results displayed, out of which 10 were relevant to the review. These were selected and reviewed. Appropriate cross-references within the articles along with Cochrane reviews were also considered and studied.

  7. Enhancement of galaxy images for improved classification

    Science.gov (United States)

    Jenkinson, John; Grigoryan, Artyom M.; Agaian, Sos S.

    2015-03-01

    In this paper, the classification accuracy of galaxy images is demonstrated to be improved by enhancing the galaxy images. Galaxy images often contain faint regions that are of similar intensity to stars and the image background, resulting in data loss during background subtraction and galaxy segmentation. Enhancement darkens these faint regions, enabling them to be distinguished from other objects in the image and the image background, relative to their original intensities. The heap transform is employed for the purpose of enhancement. Segmentation then produces a galaxy image which closely resembles the structure of the original galaxy image, and one that is suitable for further processing and classification. 6 Morphological feature descriptors are applied to the segmented images after a preprocessing stage and used to extract the galaxy image structure for use in training the classifier. The support vector machine learning algorithm performs training and validation of the original and enhanced data, and a comparison between the classification accuracy of each data set is included. Principal component analysis is used to compress the data sets for the purpose of classification visualization and a comparison between the reduced and original feature spaces. Future directions for this research include galaxy image enhancement by various methods, and classification performed with the use of a sparse dictionary. Both future directions are introduced.

  8. Contrast-enhanced breast ultrasonography: imaging features with histopathologic correlation.

    Science.gov (United States)

    Liu, He; Jiang, Yu-Xin; Liu, Ji-Bin; Zhu, Qing-Li; Sun, Qiang; Chang, Xiao-Yan

    2009-07-01

    The purpose of this study was to identify histopathologic correlates for the varied appearances of breast masses on contrast-enhanced ultrasonography (CEUS). Contrast-enhanced ultrasonography was performed in 104 patients (age range, 19-86 years) after administration of a sulfur hexafluoride microbubble contrast agent, and enhancement patterns were classified as no enhancement, peripheral enhancement, homogeneous enhancement, regional enhancement, and heterogeneous enhancement. All patients' histologic slides were reviewed and correlated with CEUS findings. In malignant masses, heterogeneous enhancement corresponded to tumor cell cords or clusters in a variable amount of desmoplastic stroma. Homogeneous enhancement corresponded to hypercellularity in the whole mass, or ductal carcinoma in situ (DCIS) was predominant. Regional enhancement corresponded to a DCIS component. Peripheral enhancement corresponded to a DCIS component, hypercellularity or adenosis at the periphery, and low-degree cellularity, degeneration, fibrosis, or necrosis in the center. No enhancement was present in 1 case of low-grade DCIS. In benign masses, heterogeneous enhancement corresponded to loose cell proliferation in a more sclerotic stroma. Homogeneous enhancement corresponded to diffuse hypercellularity, an inflammatory cell infiltrate, or intraductal papilloma. Regional enhancement corresponded to focal hypercellularity or intraductal papilloma within a dilated duct. No enhancement corresponded to desmoplastic stroma. Peripheral enhancement was shown in 1 case of granulomatous mastitis with an inflammatory infiltrate at the periphery and necrosis in the center. Breast mass CEUS findings correlated with histologic features.

  9. Evaluation of the early enhancement of coronary atherosclerotic plaque by contrast-enhanced MR angiography

    Energy Technology Data Exchange (ETDEWEB)

    Li Tao [Department of Radiology, The General Hospital of Chinese People' s Armed Police Forces, Number 69, Yong Ding Road, Hai Dian District, Beijing (China); Department of Radiology, Chinese People' s Liberation Army General Hospital, Number 28, Fu Xing Road, Hai Dian District, Beijing (China); Zhao Xihai [Department of Radiology, Chinese People' s Liberation Army General Hospital, Number 28, Fu Xing Road, Hai Dian District, Beijing (China); Liu Xin [Paul C. Lauterbur Biomedical Imaging Center, Institute of Biomedical and Health Engineering, Shenzhen Institute of Advanced Technology, Chinese Academy of Science, Shenzhen 518067 (China); Gao Jianhua [Department of Radiology, The General Hospital of Chinese People' s Armed Police Forces, Number 69, Yong Ding Road, Hai Dian District, Beijing (China); Zhao Shaohong [Department of Radiology, Chinese People' s Liberation Army General Hospital, Number 28, Fu Xing Road, Hai Dian District, Beijing (China); Li Xin; Zhou Weihua [Department of Radiology, The General Hospital of Chinese People' s Armed Police Forces, Number 69, Yong Ding Road, Hai Dian District, Beijing (China); Cai Zulong [Department of Radiology, Chinese People' s Liberation Army General Hospital, Number 28, Fu Xing Road, Hai Dian District, Beijing (China); Zhang Weiguo [Cardiovascular and Neurological Consulting Institute, 6771 San Fernando, Irving, TX 75039 (United States); Yang Li, E-mail: Yangli301@yahoo.com [Department of Radiology, Chinese People' s Liberation Army General Hospital, Number 28, Fu Xing Road, Hai Dian District, Beijing (China)

    2011-10-15

    Purpose: To evaluate the early enhancement of coronary atherosclerotic plaque using contrast-enhanced MR angiography (CE-MRA) and investigate the association between unstable angina pectoris (UAP) and early enhancement of the plaque. Methods: Forty-one patients presenting with angina pectoris and demonstrating single-vessel disease with non-calcified plaque and significant coronary stenosis ({>=}50%) on CTA were consecutively recruited for coronary CE-MRA. Contrast-to-noise ratio of the culprit plaque guided by CTA was measured on a cross-sectional multi-planar reconstruction image of the plaque on both pre- and post-CE-MRA. A 50% increasing of CNR was defined as plaque enhancement. The association between early enhancement of the plaques and UAP was analyzed. Results: Thirty-seven non-calcified plaques with significant coronary stenosis were detected in the 37 patients on MRA. 4 subjects were excluded because coronary atherosclerotic plaques were inadequate for identification on MRA. Of the 37 patients, 18 patients had UAP and other 19 patients presented stable angina pectoris (SAP). Of the 37 plaques on CE-MRA, 13 and 24 plaques presented early enhancement and no enhancement, respectively. Of the 13 early-enhanced plaques, 11 (85%) and 2 (15%) were found in the patients with UAP and SAP, respectively (p < 0.01). Of the 37 patients, 11 (61%) with UAP and 2 (11%) with SAP had early-enhanced plaques, respectively (p < 0.01). Conclusion: CE-MRA allows detection of early enhancement of coronary atherosclerotic plaque. The early enhancement is common in unstable angina and could be a sign of vulnerability.

  10. Infrared image enhancement using Cellular Automata

    Science.gov (United States)

    Qi, Wei; Han, Jing; Zhang, Yi; Bai, Lian-fa

    2016-05-01

    Image enhancement is a crucial technique for infrared images. The clear image details are important for improving the quality of infrared images in computer vision. In this paper, we propose a new enhancement method based on two priors via Cellular Automata. First, we directly learn the gradient distribution prior from the images via Cellular Automata. Second, considering the importance of image details, we propose a new gradient distribution error to encode the structure information via Cellular Automata. Finally, an iterative method is applied to remap the original image based on two priors, further improving the quality of enhanced image. Our method is simple in implementation, easy to understand, extensible to accommodate other vision tasks, and produces more accurate results. Experiments show that the proposed method performs better than other methods using qualitative and quantitative measures.

  11. Enhancing the magnetic properties of magnetic nanoparticles

    DEFF Research Database (Denmark)

    Ahlburg, Jakob; Saura-Múzquiz, Matilde; Stingaciu, Marian

    ways of enhancing magnetic properties of 3d magnetic compounds. This includes, size control, core-shell particles or mixing hard and soft magnetic materials together to achieve an exchange coupling between the compounds and enhancing the magnetic energy product. In order to control the particle size......Enhancing the magnetic properties of magnetic nanoparticles J. V. Ahlburg, M. S. Músquiz, C. Zeuthen, S. Kjeldgaard, M. Stingaciu, M. Christensen Center for Materials Crystallography, Departement of Chemistry & iNano, Aarhus University, Denmark Strong magnets with a high energy product are vital...... when optimizing the efficiency in the electric industry. But since the rare earth metals, normally used for making strong permanent magnets, are both expensive and difficult to mine, a great demand has come to cheaper types of magnets with a similar magnetic performance. There are several different...

  12. Exhaust powered drive shaft torque enhancer

    Energy Technology Data Exchange (ETDEWEB)

    Koch, A.B.

    1986-09-30

    This patent describes a power producing combination including an internal combustion engine and a mounting frame therefor, and power transmission means including rotating drive shaft means connected to the engine. The improvement described here is a drive shaft torque enhancing device, the device comprising: a multiplicity of blades secured to the drive shaft, equally spaced therearound, each generally lying in a plane containing the axis of the drive shaft; torque enhancer feed duct means for selectively directing a stream of exhaust gases from the engine to impact against the blades to impart torque to the drive shaft; and wherein the power producing combination is used in a vehicle, the vehicle having braking means including a brake pedal; and the power producing combination further comprising torque enhancer disengagement means responsive to motion of the brake pedal.

  13. Electric dipole moment enhancement factor of thallium

    Science.gov (United States)

    Porsev, Sergey; Safronova, Marianna; Kozlov, Mikhail

    2012-06-01

    A number of extensions of the standard model of particle physics predict electric dipole moments (EDM) of particles that may be observable with the present state-of-the art experiments. The EDMs arise from the violations of both parity and time-reversal invariance. The electron EDM is enhanced in certain atomic and molecular systems. One of the most stringent limits on the electron EDM de was obtained from the experiments with ^205Tl: decontroversy in the value of the EDM enhancement factor K in Tl. We have carried out several calculations by different high-precision methods, studied previously omitted corrections, as well as tested our methodology on other parity conserving quantities. We find the EDM enhancement factor of Tl to be equal to -573(20). This value is 20% larger than the recently published result of Nataraj et al. [PRL 106, 200403 (2011)] but agrees very well with several earlier results.

  14. Enhanced depth perception using hyperstereo vision

    Science.gov (United States)

    Watkins, Wendell R.

    1997-06-01

    Recent stereo vision experiments demonstrated the enhancement of depth perception over single line of sight vision for improved vehicular navigation and target acquisition processes. The experiments involves the use of stereo vision headsets connected to visible and 8 - 12 micrometers IR imagers. The imagers were separated by up to 50 m (i.e., wider platform separation than human vision, or hyperstereo) and equipped with telescopes for viewing at ranges of tens of meters up to 4 km. The important findings were: (1) human viewers were able to discern terrain undulations for obstacle avoidance for vehicular navigation, and (2) human viewers were able to detect depth features within the scenes that enhanced the target acquisition process over using monocular or single line of sight viewing. For vehicular navigation improvement, stereo goggles were developed for headset display and simultaneous see through instrumentation viewing for vehicular navigation enhancement. For detection, the depth cues can be used to detect even salient target features.

  15. Does coherence enhance transport in photosynthesis?

    CERN Document Server

    Kassal, Ivan; Rahimi-Keshari, Saleh

    2012-01-01

    Recent observations of coherence in photosynthetic complexes have led to the question of whether quantum effects can occur in vivo, not under femtosecond laser pulses but in incoherent sunlight and at steady state, and, if so, whether the coherence explains the high exciton transfer efficiency. We distinguish several types of coherence and show that although some photosynthetic pathways are partially coherent processes, photosynthesis in nature proceeds through stationary states. This distinction allows us to rule out several mechanisms of transport enhancement in sunlight. In particular, although they are crucial for understanding exciton transport, neither wavelike motion nor microscopic coherence, on their own, enhance the efficiency. By contrast, two partially coherent mechanisms---ENAQT and supertransfer---can enhance transport even in sunlight and thus constitute motifs for the optimisation of artificial sunlight harvesting. Finally, we clarify the importance of ultrafast spectroscopy in understanding i...

  16. Proniosomes for Penetration Enhancement in Transdermal System

    Directory of Open Access Journals (Sweden)

    Samita Singla

    2012-06-01

    Full Text Available Over the last few years an inclusive research has been done over provesicular approach for transdermal drug delivery. Skin has a very tough diffusion barrier inhibiting penetration of drug moiety which is rate limiting barrier for penetration of drugs. There are several approaches that deal with penetration enhancement across the skin. Vesicular and provesicular systems are promising amongst them. Vesicular systems including (niosomes, ethosomes, transfersomes and liposomes are promising systems to cross this permeation barrier. But their major drawback is their unstability, which can be overcome by using provesicular approaches like proniosomes, protransfersomes and proliposomes. Provesicular approaches have been proposed to enhance the stability of vesicles. These approaches may overcome skin barrier properties and enhance percutaneous absorption. In these systems both type of drugs, hydrophilic and lipophillic drugs can be incorporated. The focus of this review is to bring together different aspects related to mechanism of skin permeation of provesicular system, proniosomes preparation and its applications as a carrier system

  17. Biomoral Enhancement. Definizioni e problemi aperti

    Directory of Open Access Journals (Sweden)

    Luca Lo Sapio

    2014-12-01

    Full Text Available This paper focuses on the important disputation about biomoral enhancement, the new frontier of human enhancement international debate. In the first part, it analyses the main issues of Unfit for the future, the 2012 book of Savulescu and Persson, which represents a very relevant step within this theme. In the second part, it considers some arguments against Persson and Savulescu’s thesis and their own replies. Finally, it develops some arguments to show the difficulties related to the idea that it is possible to clearly understand the nature of a moral enhancement and point out the hurdle to circumscribe the basic elements we have to intervene on in order to obtain a real improvement of human moral attitudes.

  18. Enhanced Transmission through the Nanoparticle Coat

    Energy Technology Data Exchange (ETDEWEB)

    Song, G; Yu, L; Liu, B; Li, T, E-mail: candlesinwind@gmail.com [School of Science, Beijing University of Posts and Telecommunications, Beijing, 100876 (China)

    2011-02-01

    By using the full-vectorial three-dimensional finite-difference time-domain method and the perfect electronic conductor as the materials, we studied the enhanced transmission spectra through a substrate with the perfect electronic conductor nanoparticle coat. Single metal nanoparticle exhibited characteristic localized surface plasmon modes. By placing more plasmonic nanoparticles close to each other to make up of a plane, it was possible to observe the interaction between the modes of each individual nanostructure. The results showed that the enhanced transmission spectra through a substrate with different nanoparticle coats which were made by different numbers of the layers or by different metals exhibited different peaks whose values could reach 1. The number of the nanoparticle coat layers influenced the number and the positions of the enhanced transmission peaks.

  19. Enhanced Graphene Photodetector with Fractal Metasurface

    DEFF Research Database (Denmark)

    Fang, Jieran; Wang, Di; DeVault, Clayton T

    2017-01-01

    Graphene has been demonstrated to be a promising photodetection material because of its ultrabroadband optical absorption, compatibility with CMOS technology, and dynamic tunability in optical and electrical properties. However, being a single atomic layer thick, graphene has intrinsically small...... optical absorption, which hinders its incorporation with modern photodetecting systems. In this work, we propose a gold snowflake-like fractal metasurface design to realize broadband and polarization-insensitive plasmonic enhancement in graphene photodetector. We experimentally obtain an enhanced...... photovoltage from the fractal metasurface that is an order of magnitude greater than that generated at a plain gold-graphene edge and such an enhancement in the photovoltage sustains over the entire visible spectrum. We also observed a relatively constant photoresponse with respect to polarization angles...

  20. Classical enhancement of quantum vacuum fluctuations

    CERN Document Server

    De Lorenci, V A

    2016-01-01

    We propose a mechanism for the enhancement of vacuum fluctuations by means of a classical field. The basic idea is that if an observable quantity depends quadratically upon a quantum field, such as the electric field, then the application of a classical field produces a cross term between the classical and quantum fields. This cross term may be significantly larger than the purely quantum part, but also undergoes fluctuations driven by the quantum field. We illustrate this effect in a model for lightcone fluctuations involving pulses in a nonlinear dielectric. Vacuum electric field fluctuations produce fluctuations in the speed of a probe pulse, and form an analog model for quantum gravity effects. If the material has a nonzero third-order susceptibility, then the fractional light speed fluctuations are proportional to the square of the fluctuating electric field. Hence the application of a classical electric field can enhance the speed fluctuations. We give an example where this enhancement can be an increas...

  1. Enhanced index tracking modelling in portfolio optimization

    Science.gov (United States)

    Lam, W. S.; Hj. Jaaman, Saiful Hafizah; Ismail, Hamizun bin

    2013-09-01

    Enhanced index tracking is a popular form of passive fund management in stock market. It is a dual-objective optimization problem, a trade-off between maximizing the mean return and minimizing the risk. Enhanced index tracking aims to generate excess return over the return achieved by the index without purchasing all of the stocks that make up the index by establishing an optimal portfolio. The objective of this study is to determine the optimal portfolio composition and performance by using weighted model in enhanced index tracking. Weighted model focuses on the trade-off between the excess return and the risk. The results of this study show that the optimal portfolio for the weighted model is able to outperform the Malaysia market index which is Kuala Lumpur Composite Index because of higher mean return and lower risk without purchasing all the stocks in the market index.

  2. Enhanced photoacoustic detection using photonic crystal substrate

    Energy Technology Data Exchange (ETDEWEB)

    Zhao, Yunfei; Liu, Kaiyang [Department of Electrical and Computer Engineering, Iowa State University, Ames, Iowa 50011 (United States); McClelland, John [Ames Laboratory-USDOE, Ames, Iowa 50011 (United States); Department of Mechanical Engineering, Iowa State University, Ames, Iowa 50011 (United States); Department of Biochemistry, Biophysics, and Molecular Biology, Iowa State University, Ames, Iowa 50011 (United States); Lu, Meng, E-mail: menglu@iastate.edu [Department of Electrical and Computer Engineering, Iowa State University, Ames, Iowa 50011 (United States); Department of Mechanical Engineering, Iowa State University, Ames, Iowa 50011 (United States)

    2014-04-21

    This paper demonstrates the enhanced photoacoustic sensing of surface-bound light absorbing molecules and metal nanoparticles using a one-dimensional photonic crystal (PC) substrate. The PC structure functions as an optical resonator at the wavelength where the analyte absorption is strong. The optical resonance of the PC sensor provides an intensified evanescent field with respect to the excitation light source and results in enhanced optical absorption by surface-immobilized samples. For the analysis of a light absorbing dye deposited on the PC surface, the intensity of photoacoustic signal was enhanced by more than 10-fold in comparison to an un-patterned acrylic substrate. The technique was also applied to detect gold nanorods and exhibited more than 40 times stronger photoacoustic signals. The demonstrated approach represents a potential path towards single molecule absorption spectroscopy with greater performance and inexpensive instrumentation.

  3. Enhancement stimulants: perceived motivational and cognitive advantages

    Directory of Open Access Journals (Sweden)

    Irena P. Ilieva

    2013-10-01

    Full Text Available Psychostimulants like Adderall and Ritalin are widely used for cognitive enhancement by people without ADHD, although the empirical literature has shown little conclusive evidence for effectiveness in this population. This paper explores one potential explanation of this discrepancy: the possibility that the benefit from enhancement stimulants is at least in part motivational, rather than purely cognitive. We review relevant laboratory, survey and interview research and present the results of a new survey of enhancement users with the goal of comparing perceived cognitive and motivational effects. These users perceived stimulant effects on motivationally-related factors, especially energy and motivation, and reported motivational effects to be at least as pronounced as cognitive effects, including effects on "attention."

  4. Enhancing placebo effects: insights from social psychology.

    Science.gov (United States)

    Sliwinski, Jim; Elkins, Gary R

    2013-01-01

    Placebo effects are widely recognized as having a potent impact upon treatment outcomes in both medical and psychological interventions, including hypnosis. In research utilizing randomized clinical trials, there is usually an effort to minimize or control placebo effects. However, in clinical practice there may be significant benefits in enhancing placebo effects. Prior research from the field of social psychology has identified three factors that may enhance placebo effects, namely: priming, client perceptions, and the theory of planned behavior. These factors are reviewed and illustrated via a case example. The consideration of social-psychological factors to enhance positive expectancies and beliefs has implications for clinical practice as well as future research into hypnotic interventions.

  5. Mechanisms of enhanced lung injury during sepsis

    DEFF Research Database (Denmark)

    Czermak, B J; Breckwoldt, M; Ravage, Z B;

    1999-01-01

    A major complication in sepsis is progressively impaired lung function and susceptibility to intrapulmonary infection. Why sepsis predisposes the lung to injury is not clear. In the current studies, rats were rendered septic by cecal ligation/puncture and evaluated for increased susceptibility...... to injury after a direct pulmonary insult (deposition of IgG immune complexes or airway instillation of lipopolysaccharide). By itself, cecal ligation/puncture did not produce evidence of lung injury. However, after a direct pulmonary insult, lung injury in septic animals was significantly enhanced...... or treatment with anti-C5a abolished all evidence of enhanced lung injury in septic animals. When stimulated in vitro, bronchoalveolar lavage macrophages from septic animals had greatly enhanced CXC chemokine responses as compared with macrophages from sham-operated animals or from septic animals that had been...

  6. Lift enhancement by bats' dynamically changing wingspan

    Science.gov (United States)

    Wang, Shizhao; Zhang, Xing; He, Guowei; Liu, Tianshu

    2015-01-01

    This paper elucidates the aerodynamic role of the dynamically changing wingspan in bat flight. Based on direct numerical simulations of the flow over a slow-flying bat, it is found that the dynamically changing wingspan can significantly enhance the lift. Further, an analysis of flow structures and lift decomposition reveal that the elevated vortex lift associated with the leading-edge vortices intensified by the dynamically changing wingspan considerably contributed to enhancement of the time-averaged lift. The nonlinear interaction between the dynamically changing wing and the vortical structures plays an important role in the lift enhancement of a flying bat in addition to the geometrical effect of changing the lifting-surface area in a flapping cycle. In addition, the dynamically changing wingspan leads to the higher efficiency in terms of generating lift for a given amount of the mechanical energy consumed in flight. PMID:26701882

  7. Capability enhancement in compact digital holographic microscopy

    Science.gov (United States)

    Qu, Weijuan; Wen, Yongfu; Wang, Zhaomin; Yang, Fang; Asundi, Anand

    2015-03-01

    A compact reflection digital holographic microscopy (DHM) system integrated with the light source and optical interferometer is developed for 3D topographic characterization and real-time dynamic inspection for Microelectromechanical systems (MEMS). Capability enhancement methods in lateral resolution, axial resolving range and large field of view for the compact DHM system are presented. To enhance the lateral resolution, the numerical aperture of a reflection DHM system is analyzed and optimum designed. To enhance the axial resolving range, dual wavelengths are used to extend the measuring range. To enable the large field of view, stitching of the measurement results is developed in the user-friendly software. Results from surfaces structures on silicon wafer, micro-optics on fused silica and dynamic inspection of MEMS structures demonstrate applications of this compact reflection digital holographic microscope for technical inspection in material science.

  8. Signal Enhancement with Variable Span Linear Filters

    DEFF Research Database (Denmark)

    Benesty, Jacob; Christensen, Mads Græsbøll; Jensen, Jesper Rindom

    -to-noise ratio, Wiener, and tradeoff filters (including their new generalizations) can be obtained using the variable span filter framework. It then illustrates how the variable span filters can be applied in various contexts, namely in single-channel STFT-based enhancement, in multichannel enhancement in both......This book introduces readers to the novel concept of variable span speech enhancement filters, and demonstrates how it can be used for effective noise reduction in various ways. Further, the book provides the accompanying Matlab code, allowing readers to easily implement the main ideas discussed....... Variable span filters combine the ideas of optimal linear filters with those of subspace methods, as they involve the joint diagonalization of the correlation matrices of the desired signal and the noise. The book shows how some well-known filter designs, e.g. the minimum distortion, maximum signal...

  9. On Sommerfeld enhancement of Dark Matter Annihilation

    CERN Document Server

    Hannestad, Steen

    2010-01-01

    In the last few years there has been some interest in WIMP Dark Matter models featuring a velocity dependent cross section through the Sommerfeld enhancement mechanism. The idea is to have light bosons mediate a force between the WIMPs, which gives rise to a Yukawa-potential. In the first part of this article, we analyse the Sommerfeld enhancement in detail. We find analytic expressions for the boost factor for three different modelpotentials, Coulomb, the spherical well and the spherical cone well and compare with the numerical solution in the Yukawa case. In the second part of the article, we perform a detailed computation of the Dark Matter relic density for models having Sommerfeld enhancement by solving the Boltzmann equation numerically. As an application we compare the expected distortions of the CMB blackbody spectrum to the bounds set by FIRAS.

  10. Enhanced oil recovery with polymer flooding

    Science.gov (United States)

    Parsa, Shima; Weitz, David

    2016-11-01

    Polymer flooding is a method for enhanced oil recovery, however the mechanism responsible for the effectiveness of polymer flooding is not well understood. We use confocal microscopy and bulk transport measurements to probe the effectiveness of different molecular weight and concentrations of Polyacrylamide solution in imbibition of crude oil in 3D micromodel. We show that large molecular weight and moderate to high concentration of polymer is required for enhanced recovery. By directly measuring the pore level velocities in the medium, we show that polymer retention in the medium results in diversion of flow in some pores. The inhomogeneous changes in the flow velocities result in redistribution of viscous forces and enhanced recovery of oil.

  11. Rational Design of Biobetters with Enhanced Stability.

    Science.gov (United States)

    Courtois, Fabienne; Schneider, Curtiss P; Agrawal, Neeraj J; Trout, Bernhardt L

    2015-08-01

    Biotherapeutics are the fastest growing class of pharmaceutical with a rapidly evolving market facing the rise of biosimilar and biobetter products. In contrast to a biosimilar, which is derived from the same gene sequence as the innovator product, a biobetter has enhanced properties, such as enhanced efficacy or reduced immunogenicity. Little work has been carried out so far to increase the intrinsic stability of biotherapeutics via sequence changes, even though, aggregation, the primary degradation pathway of proteins, leads to issues ranging from manufacturing failure to immunological response and to loss of therapeutic activity. Using our spatial aggregation propensity tool as a first step to a rational design approach to identify aggregation-prone regions, biobetters of rituximab have been produced with enhanced stability by introducing site-specific mutations. Significant stabilization against aggregation was achieved for rituximab with no decrease in its binding affinity to the antigen.

  12. Proposal of Enhanced Extreme Programming Model

    Directory of Open Access Journals (Sweden)

    M. Rizwan Jameel Qureshi

    2015-01-01

    Full Text Available Extreme programming is one of the commonly used agile methodologies in software development. It is very responsive to changing requirements even in the late phases of the project. However, quality activities in extreme programming phases are implemented sequentially along with the activities that work on the functional requirements. This reduces the agility to deliver increments continuously and makes an inverse relationship between quality and agility. Due to this relationship, extreme programming does not consume enough time on making extensive documentation and robust design. To overcome these issues, an enhanced extreme programming model is proposed. Enhanced extreme programming introduces parallelism in the activities' execution through putting quality activities into a separate execution line. In this way, the focus on delivering increments quickly is achieved without affecting the quality of the final output. In enhanced extreme programming, the quality concept is extended to include refinement of all phases of classical extreme programming and creating architectural design based on the refined design documents.

  13. Phase difference enhancement with classical intensity interferometry

    Science.gov (United States)

    Shirai, Tomohiro

    2016-12-01

    It is demonstrated theoretically and experimentally that, as a novel function of classical intensity interferometry, a phase difference distribution recorded in the form of an interferogram can be enhanced by a factor of 2 on the basis of the classical intensity correlation. Such phase difference enhancement which is also referred to as phase difference amplification is, in general, known to be practically important since it increases sensitivity and accuracy in interferometric measurements. The method proposed in this study prevails over the existing methods in the sense that it can be readily implemented without difficulty in comparison with all other methods so far proposed, although the phase difference enhancement is limited to a factor of 2 in our method and thus so is the improvement of sensitivity and accuracy.

  14. BIR 2014 - Bibliometric-enhanced Information Retrieval

    DEFF Research Database (Denmark)

    This first “Bibliometric-enhanced Information Retrieval” (BIR 2014) workshop1 aims to engage with the IR community about possible links to bibliometrics and scholarly communication. Bibliometric techniques are not yet widely used to enhance retrieval processes in digital libraries, although...... analysis of co-authorship network, can improve retrieval services for specific communities, as well as for large, cross-domain collections. This workshop aims to raise awareness of the missing link between information retrieval (IR) and bibliometrics / scientometrics and to create a common ground...... for the incorporation of bibliometric-enhanced services into retrieval at the digital library interface. Our interests include information retrieval, information seeking, science modelling, network analysis, and digital libraries. The goal is to apply insights from bibliometrics, scientometrics, and informetrics...

  15. A Confucian reflection on genetic enhancement.

    Science.gov (United States)

    Fan, Ruiping

    2010-04-01

    This essay explores a proper Confucian vision on genetic enhancement. It argues that while Confucians can accept a formal starting point that Michael Sandel proposes in his ethics of giftedness, namely, that children should be taken as gifts, Confucians cannot adopt his generalist strategy. The essay provides a Confucian full ethics of giftedness by addressing a series of relevant questions, such as what kind of gifts children are, where the gifts are from, in which way they are given, and for what purpose they are given. It indicates that Confucians should sort out different types of enhancement and bring them to the test of the Confucian values in terms of both Confucian virtue principles and specific ritual rules. It concludes that Confucians can accept some types of enhancement but must reject others.

  16. Surface enhanced raman spectroscopy on chip

    DEFF Research Database (Denmark)

    Hübner, Jörg; Anhøj, Thomas Aarøe; Zauner, Dan

    2007-01-01

    In this paper we report low resolution surface enhanced Raman spectra (SERS) conducted with a chip based spectrometer. The flat field spectrometer presented here is fabricated in SU-8 on silicon, showing a resolution of around 3 nm and a free spectral range of around 100 nm. The output facet...... is projected onto a CCD element and visualized by a computer. To enhance the otherwise rather weak Raman signal, a nanosurface is prepared and a sample solutions is impregnated on this surface. The surface enhanced Raman signal is picked up using a Raman probe and coupled into the spectrometer via an optical...... fiber. The obtained spectra show that chip based spectrometer together with the SERS active surface can be used as Raman sensor....

  17. Image Enhancement Using DWT DCT and SVD

    Directory of Open Access Journals (Sweden)

    Aswathy Mohan,

    2014-04-01

    Full Text Available Image enhancement deals with enhancing the image so that it provides more details. Several techniques are proposed for contrast enhancement of a low-contrast satellite images and CT scans. Here a new technique has been proposed based on the Discrete Wavelet Transform(DWT Singular Value Decomposition (SVD and Discrete Cosine Transform (DCT. The proposed technique divides image into blocks and converts each block of image into the DWT-SVD-DCT domain after normalizing the singular value matrix. Then the modified image is reconstructed by using inverse DCT and DWT and the blocks are combined. Adaptive Histogram Equalization (AHE has been used here. Results of the proposed method clearly indicates increased efficiency and flexibility perceptually and quantitatively over the existing methods like DWT-SVD technique.

  18. Intravenous magnetic resonance arthrography of the knee

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Jung Hyeon; Lee, Young Uk; Suh, Jong Dae; Lee, Seung Hee; Kim, Dong Joo [Kangbuk Samsung Hospital, Seoul (Korea, Republic of)

    1995-10-15

    Knee MR images were repeatedly obtained after intravenous administration of gadopentetate dimeglumine to evaluate the arthrographic effect and to determine the optimal scan timing and technique. Sagittal T1-weighted (650/15) sequences were repeated before and after intravenous gadolinium enhancement in 26 patients who were divided into exercise (14/26) and nonexercise (12/26) groups. Fourteen patients in exercise group were allowed to move the affected knee joint actively for 10 minutes immediately after the first post-enhancement scan and before repeating scans. The signal intensities in central and peripheral portions of the joint were measured and compared between these two groups. In all cases, enhancement of joint fluid began at peripheral portion and progressed toward central portion. The diffusion rate in exercise group was far faster than that in nonexercise group and homogeneous arthrographic image was revealed within 10 minutes after completion of joint movement. The arthrographic effect continued and the rate of signal decrease was quite slow. MR arthrographic image of knee joint can be obtained within 10 minutes after completion of a few minute exercise following intravenous injection of gadopentetate dimeglumine. Intravenous MR arthrography is expected to become an useful method as a convenient alternative to direct MR arthrography.

  19. Surface-Enhanced X-Ray Fluorescence

    Science.gov (United States)

    Anderson, Mark

    2010-01-01

    Surface-enhanced x-ray fluorescence (SEn-XRF) spectroscopy is a form of surface- enhanced spectroscopy that was conceived as a means of obtaining greater sensitivity in x-ray fluorescence (XRF) spectroscopy. As such, SEn-XRF spectroscopy joins the ranks of such other, longer-wavelength surface-enhanced spectroscopies as those based on surface-enhanced Raman scattering (SERS), surface-enhanced resonance Raman scattering (SERRS), and surfaceenhanced infrared Raman absorption (SEIRA), which have been described in previous NASA Tech Briefs articles. XRF spectroscopy has been used in analytical chemistry for determining the elemental compositions of small samples. XRF spectroscopy is rapid and quantitative and has been applied to a variety of metal and mineralogical samples. The main drawback of XRF spectroscopy as practiced heretofore is that sensitivity has not been as high as required for some applications. In SEn-XRF as in the other surface-enhanced spectroscopies, one exploits several interacting near-field phenomena, occurring on nanotextured surfaces, that give rise to local concentrations of incident far-field illumination. In this case, the far-field illumination comes from an x-ray source. Depending on the chemical composition and the geometry of a given nanotextured surface, these phenomena could include the lightning-rod effect (concentration of electric fields at the sharpest points on needlelike surface features), surface plasmon resonances, and grazing incidence geometric effects. In the far field, the observable effect of these phenomena is an increase in the intensity of the spectrum of interest - in this case, the x-ray fluorescence spectrum of chemical elements of interest that may be present within a surface layer at distances no more than a few nanometers from the surface.

  20. Dengue virus antibodies enhance Zika virus infection

    Science.gov (United States)

    Paul, Lauren M; Carlin, Eric R; Jenkins, Meagan M; Tan, Amanda L; Barcellona, Carolyn M; Nicholson, Cindo O; Michael, Scott F; Isern, Sharon

    2016-01-01

    For decades, human infections with Zika virus (ZIKV), a mosquito-transmitted flavivirus, were sporadic, associated with mild disease, and went underreported since symptoms were similar to other acute febrile diseases. Recent reports of severe disease associated with ZIKV have greatly heightened awareness. It is anticipated that ZIKV will continue to spread in the Americas and globally where competent Aedes mosquito vectors are found. Dengue virus (DENV), the most common mosquito-transmitted human flavivirus, is both well-established and the source of outbreaks in areas of recent ZIKV introduction. DENV and ZIKV are closely related, resulting in substantial antigenic overlap. Through antibody-dependent enhancement (ADE), anti-DENV antibodies can enhance the infectivity of DENV for certain classes of immune cells, causing increased viral production that correlates with severe disease outcomes. Similarly, ZIKV has been shown to undergo ADE in response to antibodies generated by other flaviviruses. We tested the neutralizing and enhancing potential of well-characterized broadly neutralizing human anti-DENV monoclonal antibodies (HMAbs) and human DENV immune sera against ZIKV using neutralization and ADE assays. We show that anti-DENV HMAbs, cross-react, do not neutralize, and greatly enhance ZIKV infection in vitro. DENV immune sera had varying degrees of neutralization against ZIKV and similarly enhanced ZIKV infection. Our results suggest that pre-existing DENV immunity may enhance ZIKV infection in vivo and may lead to increased disease severity. Understanding the interplay between ZIKV and DENV will be critical in informing public health responses and will be particularly valuable for ZIKV and DENV vaccine design and implementation strategies. PMID:28090318