WorldWideScience
1

Myocardial perfusion SPECT in patients after myocardial infarction: Comparison of "2"0"1Tl and dual-isotope protocol (rest "2"0"1Tl/stress "9"9"mTc tetrofosmin)  

International Nuclear Information System (INIS)

The diagnostic accuracy is compared of the dual-isotope protocol and the conventional "2"0"1Tl protocol, for detection of the coronary artery disease (CAD) using data on a total of 69 patients after myocardial infarction (MI). The "2"0"1Tl protocol was used to examine 44 patients, the dual-isotope protocol was used with 25 patients. All patients were examined by coronarography; a narrowing of the artery by more than 50 % was considered significant for CAD. The sensitivity, specificity and diagnostic accuracy was 97.7 %, 100 % and 97.7 % resp. for the "2"0"1Tl protocol, and 95.2 %, 75 % and 92 % resp. for the dual-isotope protocol. A higher diagnostic accuracy of the dual-isotope protocol has not been proven, and the "2"0"1Tl protocol continues to be used for examinations of patients after MI

1998-08-01

2

Effects of ischemic-like insult on myocardial /sup 201/Tl accumulation  

Energy Technology Data Exchange (ETDEWEB)

Despite extensive clinical use of thallium-201 (/sup 201/Tl) for myocardial imaging, the effect of ischemia on myocardial accumulation and release of /sup 201/Tl independent of flow has not been fully defined. Therefore, myocardial accumulation of /sup 201/Tl in response to ischemic-like myocardial injury was assessed in vitro using the cultured fetal mouse heart preparation. Cultured fetal mouse hearts (n . 311) were subjected to injury simulating ischemia by deprivation of oxygen and oxidizable substrates for periods ranging from 15 minutes to 10 hours. The extent of irreversible injury was determined by the percentage of lactic dehydrogenase (LDH) lost from the hearts to the culture medium during recovery from injury. Injury was essentially reversible at 1 hour of insult. The ...

1983-04-01

3

Pharmacokinetic parameters for thallium (I)-ions in man  

Energy Technology Data Exchange (ETDEWEB)

The pharmacokinetics of Tl/sup +/ were studied in 9 patients who underwent myocardial scintigraphy with /sup 201/Tl/sup +/. The time course of the /sup 201/Tl/sup +/ concentration fitted to an open two-compartment model. Using previously published dialysance values the influence of hemodialysis on Tl/sup +/ elimination was calculated. Hemodialysis in Tl/sup +/ intoxications should be moderately effective.

1983-05-01

4

Utilization of Tc-99m-TBI as a myocardial perfusion agent in exercise studies: Comparison with Tl-201 thallous chloride and examination of its biodistribution in humans  

Energy Technology Data Exchange (ETDEWEB)

Twenty-four patients were studied with both /sup 201/Tl-thallus chloride and /sup 99m/Tc-TBI scintigraphy following exercise. Comparison of the two agents in detecting segmental myocardial ischemia and scar was made in 18 patients with evidence of coronary artery disease on /sup 201/Tl-thallous chloride scintigraphy. Agreement between the two studies was observed in 77% (125 of 162) of left ventricular segments, suggesting that /sup 99m/Tc-TBI can be used as a myocardial perfusion agent. Limitations were related to early high background activity from lungs and liver. The high lung activity and early myocardial redistribution within the 1st hour contributed to the failure of /sup 99m/Tc-TBI to detect 16 segmental defects seen in the immediate post-exercise thallous chloride scan. Persistently high liver activity additionally affected accurate ...

1986-10-01

5

[sup 123]I-MIBG myocardial scintigraphy in diabetic patients. Relationship with [sup 201]Tl uptake and cardiac autonomic function  

Energy Technology Data Exchange (ETDEWEB)

The purpose of this paper is to investigate the influence of diabetic myocardial damage (suspected myocardial damage; SMD) diagnosed by [sup 201]Tl-SPECT and diabetic cardiac autonomic neuropathy (AN) on myocardial MIBG uptake in patients with NIDDM. Eighty-seven diabetic patients divided into four subgroups: 23 with SMD (+) AN (+); 19 with SMD (+) AN (-); 27 with SMD (-) AN (+); 18 with SMD (-) AN (-), and 10 controls were studied. Both planar and SPECT images were taken at 30 minutes (early) and 3 hours (delayed) after [sup 123]I-MIBG injection. The heart to mediastinum uptake ratio (H/M) and washout ratio of [sup 123]I-MIBG (WR) were obtained from both planar images. Similarly, the difference between the [sup 201]Tl image and the [sup 123]I-MIBG image in the total uptake score (TUS) was taken as the difference in the total uptake score ...

1998-12-01

6

Usefulness of myocardial imaging by [sup 123]I-MIBG in assessment of diabetic neuropathy  

Energy Technology Data Exchange (ETDEWEB)

In diabetic patients with autonomic neuropathy, it is suggested that there is a reduced uptake of [sup 123]I-metaiodobenzylguanidine (MIBG) in the heart. We compared the difference of myocardial [sup 123]I-MIBG accumulation between 4 diabetic patients with triopathy and 6 patients without it. In all 10 patients, coronary angiography and [sup 201]Tl imaging (rest and 4 hours later) were performed. [sup 123]I-MIBG (111 MBq) was administered intravenously and its imaging was recorded on 15 minutes and 4 hours after injection. In all 4 cases with triopathy, [sup 123]I-MIBG imaging showed defect in apical and inferior region. In 2 out of 6 cases without triopathy, rapid clearance was noticed in apical and inferior region. There was no significant stenosis in right coronary artery and no defect in initial and delayed [sup 201]Tl images in all cases. We concluded that diabetic autonomic ...

1993-10-01

7

[sup 123]I-MIBG myocardial scintigraphy in diabetic patients. Association with autonomic neuropathy  

Energy Technology Data Exchange (ETDEWEB)

[sup 123]I-metaiodobenzylguanidine (MIBG) myocardial scintigraphy was performed in 20 diabetic patients (NIDDM) and 8 control subjects to investigate the association between clinical autonomic nerve dysfunction and myocardial accumulation of MIBG. We used coefficient variance of R-R interval (CV[sub R-R]) as a index of the autonomic neuropathy and categorized diabetes into two groups (CV[sub R-R][>=]2.0: non-autonomic neuropathy. CV[sub R-R]<2.0: autonomic neuropathy). In planar imaging studies, heart to mediastinum MIBG uptake ratio (H/M) was calculated on both early and delayed images. The washout ratio of [sup 123]I-MIBG in the heart (%WR) was also obtained using myocardial tracer activity on the both images. Mean value of these indices in diabetic group did not reveal any significant difference with the value in the control group. On the SPECT images, low uptake was observed in the posterior-inferior wall with ...

1994-09-01

8

The present state of nuclear medicine practice in Japan; A report of the 3rd nationwide survey in 1992  

Energy Technology Data Exchange (ETDEWEB)

The Subcommittee for Surveillance of Nuclear Medicine Practice has implemented a survey for actual nuclear medicine practice in Japan every 5 years. This article reports on the third survey implemented during a one-month period in June 1992. Questionnaires were sent to all 1256 facilities employing radiopharmaceuticals in routine practice, and 1162 (92.5%) answered. In vivo nuclear medicine examinations per day were performed in 6600 cases. SPECT accounted for 19.4%, as compared with 7.1% in the 1987 survey. According to organs, the frequency of examination for the cerebrospinal region was 3.2 and 2.2 times higher than that in the 1982 and 1987 surveys, respectively, whereas for the thyroid gland it was 0.6-fold and 0.7-fold that of these surveys. The proportion of bone scintigraphy was the highest (24.5%), followed by tumor scintigraphy (14.1%) and myocardial scintigraphy (11.9%). The frequency of myocardial and cerebral blood flow ...

1993-09-01

9

Tumour affinity of [sup 203]Pb-chloride: comparison with [sup 67]Ga-citrate and [sup 201]Tl-chloride  

Energy Technology Data Exchange (ETDEWEB)

[sup 203]Pb-chloride is a promising imaging agent for tumour scanning because of the large retention value for tumour tissue and the small value for normal organs, but the large value for the kidneys and bone is a shortcoming. The retention value of [sup 203]Pb in tumour tissue is larger than that of [sup 201]Tl and smaller than that of [sup 67]Ga. The tumour/inflammatory lesion retention ratio for [sup 203]Pb is very large in comparison with those for [sup 67]Ga and [sup 201]Tl. [sup 203]Pb accumulates to a large extent in viable tumour tissue, and less in necrotic tumour tissue and in inflammatory lesion. (author).

1994-01-01

10

Production of 'no-carrier-added' "2"0"1Tl  

International Nuclear Information System (INIS)

A procedure has been developed for producing a radiopharmaceutically pure ''no-carrier-added'' "2"0"1Tl. The procedure is based on irradiating enriched metallic thallium (> 96% "2"0"3Tl) targets with approx. 30 Mev protons, separating "2"0"1Pb by co-precipitation with SrSO_4 from sulphuric acid solution, and extracting "2"0"1Tl (after its in-growth) with butyl acetate from a hydrochloric solution. The average overall yield of "2"0"1Tl is approx. 92%. The radioactive concentration of the product exceeds 2 mCi/mL; radionuclide impurities-"2"0"0Tl <= 0.5%; "2"0"2Tl <= 0.1%; "2"0"3Pb <= 0.02%; inactive impurities (#mu#g/mL)-Tl < 2, Sr < 1, Fe < 0.25, Cu < 0.05; pH within the range 5-8. The product is sterile, apyrogenic, and suitable for clinical application. (author).

11

Quantitative thallium-201 scintigraphy after dipyridamole infusion combined with low level exercise in healthy volunteers  

Energy Technology Data Exchange (ETDEWEB)

To establish test specific normal limits for quantitative analysis of uptake and washout of /sup 201/Tl after dipyridamole infusion combined with low level exercise, 20 healthy volunteers were studied with low likelihood of coronary artery disease (CAD) assessed by a stepwise probability analysis based on age, sex, symptoms, resting electrocardiogram, and exercise electrocardiography. Likelihood of CAD in these volunteers was calculated as less than or equal to 1%. After dipyridamole infusion combined with low level exercise, one volunteer complained of headache; no other side effects were observed. There were no chest pain complaints. Maximal hemodynamic changes were achieved during the 6th and 7th min of the test. No ST segment depression was recorded. Visual analysis of the /sup 201/Tl scintigrams was normal in all volunteers. Mean regional washout at 4 h was 44.37%+-2.11%. The regional washout in ...

1989-05-01

12

Thallium-201 yields and excitation functions for the lead radioactivities produced by irradiation of natural thallium with 15-60 MeV protons  

International Nuclear Information System (INIS)

Excitation functions, production yields and radionuclidic purities are described for "2"0"1Tl production by the "2"0"3Tl(p,3n) "2"0"1Pb #-># "2"0"1Tl and "2"0"5Tl(p,5n)"2"0"1Pb#->#"2"0"1Tl nuclear reactions. The yields (mCi g"-"1 cm"2/#mu#A-hr) of the parent "2"0"1Pb(9.4hr), as well as the radiocontaminants "2"0"0Pb(21.5hr), sup(202m)Pb(3.62 hr), "2"0"3Pb(52.1 hr) and sup(204m)Pb(1.115 hr) were measured by irradiating a stack of thin natural Tl foils with protons from the 76-in isochronous cyclotron at the Crocker Nuclear Laboratory. The "2"0"1Tl thick-target yield (mCi/#mu#A hr) was calculated for different target thicknesses and corresponding incident proton energies. The excitation functions for the "2"0"3Tl(p,3n)"2"0"1Pb and "2"0"5Tl(p,5n)"2"0"1Pb reactions were measured in the 15-60-MeV energy range. (author).

13

Radiometric measurement of lead-201 and thallium-201 activity in industrial production of thallium chlorides  

International Nuclear Information System (INIS)

The spectrometric methods and equipment for "2"0"1Pb and "2"0"1Tl activity control in the prepared thallium chloride in industrial production are described. Estimation of thallium-201 activity is carried out in accord with the square of summary photopeak caused by #gamma#-quanta at 167 keV energy. Attenuation is paid to spectrometer calibration. 5 refs.; 2 figs.; 2 tabs.

14

PET/CT cardiology: an area whose boundaries are still out of sight  

International Nuclear Information System (INIS)

Positron emission tomography (PET) and X-ray computed tomography (CT) performed with PET/CT cameras allow us to obtain concurrently information on the presence and degree of alterations of myocardial perfusion and metabolism and on coronary arteries calcification. Furthermore, by gated myocardial perfusion studies, PET may provide crucial information on regional coronary blood flow reserve and endothelial dysfunction. A number of recent papers provide some insight on the potential of PET/CT in cardiology and in the assessment of various cardiovascular diseases including various types of vasculitis and metabolic diseases.

2006-05-01

15

Simultaneous assessment of left ventricular function from gated myocardial perfusion SPECT. Utility of QGS (Quantitative Gated SPECT) program  

International Nuclear Information System (INIS)

Quantitative gated SPECT (QGS) was evaluated in 7 normal volunteers and 31 patients with cardiac diseases. Adequate cut off value of a prefilter was 0.45. In phantom, the left ventricular volume value was 93.9% of determined value by 180-degree projection in L type and 98.8% by 360-degree projection in opposed type. In normal volunteers, LVEF measured by QGS program related to value by first pass method. As for functional map, regional EF and wall motion decreased at the septum side, and wall thickening at base side of heart. Good correlation was recognized (p<0.0001) between blood flow image and functional map (regional EF and wall thickening). In 20 cases of acute myocardial infarction, lesion was detected conspicuously in regional EF and wall motion. The accuracy of coronary arterial stenosis improved in functional map (regional EF 92%, wall motion 92% and wall thickening 88%). In particular, the accuracy of 3 rami lesion was 100% in ...

1998-08-01

16

Modification of NPL-CRC secondary standards radionuclide calibrator holder to suit for IPEN vials  

International Nuclear Information System (INIS)

The procedure followed by the Laboratorio de Metrologia Nuclear (LMN) at the IPEN - CNEN/SP, in Sao Paulo, for modifying the NPL-CRC radionuclide sample holder in order to adapt for IPEN vials is presented. For the quality assurance of the results using the IPEN vials, the influence of variation in dimensions and volume of solution has been investigated and suitable correction factors were applied. The solutions used in the present work were "5"1Cr "9"9"mTc "1"5"3Sm, and "2"0"1Tl. (author)

2000-10-05

17

Separation of "2"0"3Pb from Tl_2O_3 target material using a hydrous zirconium oxide column with application to "2"0"1Tl preparation  

International Nuclear Information System (INIS)

Lead 203 has been used as a tracer for lead in the field of nuclear medicine for several years. It is produced in a cyclotron usually by proton or deuteron bombardment of a thallium target principally by the p,n or d,2n reaction on "2"0"3Tl or the p,3n or d,4n reaction on "2"0"5Tl. Several different methods have been reported for the separation of "2"0"3Pb from the thallium target. These generally involve a combination of precipitation and solvent extraction techniques. A new method has been developed for the separation of Pb from Tl using ion exchange chromatography over hydrous zirconium oxide (HZO). Lead is taken up by this inorganic ion exchanger at pH > 3 whereas Tl(I) is not. Lead can subsequently be eluted with acid of pH 1-1.5. The recovery of "2"0"3Pb has been approximately 75% and the Tl impurity level has not been in excess of 10 ppm. Reference is made to the application of this separation method to the preparation of "2"0"1Tl from the reaction "2"0"3Tl(p,3n)"2"0"1Pb ...

18

Separation of /sup 203/Pb by ion-exchange chromatography on Chelex 100 after production of /sup 203/Pb by the Pb(p,xn)/sup 203/Bi/sup EC. beta. +/ -> /sup 203/Pb nuclear reaction  

Energy Technology Data Exchange (ETDEWEB)

Bismuth radioisotopes, produced by 50-MeV proton bombardment of a lead target in a cyclotron, are separated from the lead target material by ion-exchange chromatography on a column containing 5.0 ml of Chelex 100. After a decay period of 24 hr, the /sup 203/Pb formed in situ is eluted from the column and then separated from /sup 200/Tl and /sup 201/Tl on a second ion-exchange column containing 0.5 ml of Chelex 100. Separations are sharp and carrier-free /sup 203/Pb is obtained.

1989-04-01

19

Preoperative image diagnosis of hypertrophied parathyroid glands in patients with renal osteodystrophy  

International Nuclear Information System (INIS)

Computed tomography (CT) of the neck and mediastinum was performed in 16 patients with renal osteodystrophy. Thirty out of 34 excised parathyroid glands weighing more than 500mg were diagnosed preoperatively (88.2%). Scintigraphy of the neck with _2_0_1TlCl and sup(99m)TcOsub(4-) was also performed in 15 patients. The introduction of subtraction method with a mini-computor in the scintigraphy has remarkably improved the visualization rate of parathyroid glands. Ultrasonic echography (US) of the neck which is able to obtain not only transverse butalso longitudinal imaging was done in 7 patients. It has about same detection rate of the glands with CT. The visualization of enlarged parathyroid glands is valuable not only for localization but also for undeniable evidence of hyperparathyroidism. Also, repeated follow-up examination can determine the effectiveness of conservative treatment. (author).

20

Image diagnosis of parathyroid glands in chronic renal failure  

Energy Technology Data Exchange (ETDEWEB)

Twenty-two out of 31 patients with chronic renal failure and secondary hyperparathyroidism who underwent parathyroidectomy before operation underwent non-invasive image diagnosis of parathyroid glands by computed tomography (CT), scintigraphy with /sup 201/TlCl and /sup 99m/TcO/sup 4 +/, and/or ultrasonography. CT visualized 39 of 45 parathyroid glands (86.7%), weighing more than 500 mg. Scintigraphy with a subtraction method using a computer performed the diagnosis in 19 of 27 glands (70.4%). Ultrasonography detected 21 of 27 glands (77.8%). Image diagnosis was also useful in the postoperative follow-up study. The non-invasive image diagnosis of parathyroid glands in patients with chronic renal failure is thus valuable for 1) definite diagnosis of secondary hyperparathyroidism, 2) localization, and 3) diagnosis for effectiveness of conservative treatment.

1983-07-01

22

Quantification of cardiac function with multislice spiral CT using retrospective EKG-gating: comparison with MRI  

International Nuclear Information System (INIS)

Purpose: To quantify left ventricular function derived from retrospectively ECG-gated multislice spiral CT (MSCT) data sets in comparison to MRI. Materials and Methods: In 16 patients (14 males, 2 females, mean age 56.8 #+-# 11.5 years), retrospectively ECG-gated MSCT angiography of the coronary arteries and breath-hold steady state free precession cine MRI were performed. From MSCT data-sets, 20 axial image series were reconstructed every 5% of the RR interval. Multiplanar images were reformatted in the short axis orientation from axial images. End-systolic and end-diastolic images were selected. From these images end-systolic volume (ESV), end-diastolic volume (EDV) and stroke volume (SV) as well as the ejection fraction (EF) and myocardial mass (MM) were determined using the Simpson's method and compared with MRI. Furthermore, image quality was assessed for both imaging modalities using a four point grading scale. ...

2003-01-01

23

Yield and excitation function measurements of some nuclear reactions on natural thallium induced by protons leading to the production of medical radioisotopes {sup 201}Tl and {sup 203}Pb  

Energy Technology Data Exchange (ETDEWEB)

Excitation functions for {sup 201}Pb, {sup 202m}Pb, {sup 203}Pb and {sup 204m}Pb radionuclides which are formed via proton induced reactions with natural thallium target have been measured from their respective threshold (E{sub thr}) to 27.5 MeV using activation technique. Natural copper foils were used to monitor the cyclotron beam. The integral yields (MBq/{mu}A h) of the produced radionuclides were calculated from the measured excitation functions. The optimum proton energy range for the production of {sup 203}Pb with low amount of impurities is (16-10 MeV) after 5 h of EOB. The experimental cross-sections for {sup nat}Tl(p,xn) reactions were compared with the cross-sections recommended by the IAEA and with earlier published data when it was possible. (orig.)

2007-07-01

24

Optimization of isotope production by cross section determination  

International Nuclear Information System (INIS)

In order to optimize the production of "2"0"1Tl and "6"7Ga using the (p, xn) reactions on enriched "2"0"3Tl and "6"8Zn targets we established a new set of cross section curves for the most relevant reactions. Target stacks made of up to 15 thin (50 #mu#m) natural Tl or Zn foils interleaved with brass degradation foils were irradiated with incident proton energies from 42 to 10 MeV in overlapping experiments. Yields for "2"0"0","2"0"1","2"0"2"m","2"0"3","2"0"4"mPB and "6"6","6"7","6"8Ga were computed from measured #gamma# emission rates. Where possible, cross section curves for the nuclear reactions involved were computed. Thick target yields and contamination ratios for enriched targets were derived and show good agreement with results from actual production runs. (orig.).

25

Measurement of relative L X-ray intensity ratio following radioactive decay and photoionization  

International Nuclear Information System (INIS)

The measurements of the L X-ray intensity ratio I(L?)/I(L?), I(L?)/I(L?), I(L?)/I(L?), I(L?)/I(L?) and I(L?)/I(L?) for elements Dy, Ho, Yb, W, Hg, Tl and Pb were experimentally determined both by photon excitation, in which 59.5 keV ?-rays from a filtered radioisotope 241Am was used, and by the radioactive decay of 160Tb, 160Er, 173Lu, 182Re, 201Tl, 203Pb and 207Bi. L X-rays emitted by samples were counted by a Si(Li) detector with resolution 160 eV at 5.9 keV. Obtained values were compared with the calculated theoretical values. Theoretical values of the I(L?/L?), I(L?/L?), I(L?/L?), I(L?/L?) and I(L?/L?) intensity ratios were calculated using theoretically tabulated values of subshell photoionization cross-section, fluorescence yield, fractional X-ray emission rates, Coster-Kronig transition probabilities. It was observed that present values agree with previous theoretical and other available experimental results.

2008-05-22

26

Measurement of relative K X-ray intensity ratio following radioactive decay and photoionization  

Energy Technology Data Exchange (ETDEWEB)

The measurements of the K X-ray intensity ratio I(K{alpha} {sub 2}/K{alpha} {sub 1}), I(K{beta} {sub 1}/K{alpha} {sub 1}) and I(K{beta}/K{alpha}) for elements V, Mn, Zn, Tc, Ru, Cd, Xe, Ba, Cs, Hg and Rn were experimentally determined both by photon excitation, in which 59.5 keV {gamma}-rays from a {sup 241}Am and 123.6 keV {gamma}-rays from a {sup 60}Co were used, and following the radioactive decay of {sup 51}Cr, {sup 55}Fe, {sup 67}Ga, {sup 99}Tc, {sup 111}In, {sup 131}I, {sup 133}Ba, {sup 133}Xe, {sup 137}Cs, {sup 201}Tl and {sup 226}Ra. K X-rays emitted by samples were counted by a Si(Li) detector with resolution 160 eV at 5.9 keV. Obtained values were compared with the theoretical values. It was observed that present values agree with the previous theoretical and other experimental results.

2007-01-15

27

Measurement of relative K X-ray intensity ratio following radioactive decay and photoionization  

International Nuclear Information System (INIS)

The measurements of the K X-ray intensity ratio I(K#alpha# _2/K#alpha# _1), I(K#beta# _1/K#alpha# _1) and I(K#beta#/K#alpha#) for elements V, Mn, Zn, Tc, Ru, Cd, Xe, Ba, Cs, Hg and Rn were experimentally determined both by photon excitation, in which 59.5 keV #gamma#-rays from a "2"4"1Am and 123.6 keV #gamma#-rays from a "6"0Co were used, and following the radioactive decay of "5"1Cr, "5"5Fe, "6"7Ga, "9"9Tc, "1"1"1In, "1"3"1I, "1"3"3Ba, "1"3"3Xe, "1"3"7Cs, "2"0"1Tl and "2"2"6Ra. K X-rays emitted by samples were counted by a Si(Li) detector with resolution 160 eV at 5.9 keV. Obtained values were compared with the theoretical values. It was observed that present values agree with the previous theoretical and other experimental results.

2007-01-01

28

Altered myocardial substrate metabolism is associated with myocardial dysfunction in early diabetic cardiomyopathy in rats: studies using positron emission tomography  

UK PubMed Central (United Kingdom)

BackgroundIn vitro data suggest that changes in myocardial substrate metabolism may contribute to impaired myocardial function in diabetic cardiomyopathy (DCM)....Full Text Available

31

Impact of the Metabolic Syndrome on the Clinical Outcome of Patients with Acute ST-Elevation Myocardial Infarction  

UK PubMed Central (United Kingdom)

We sought to determine the prevalence of metabolic syndrome (MS) in patients with acute myocardial infarction and its effect on clinical outcomes. Employing data from the Korea Acute Myocardial Infarction...Full Text Available

2010-10-01

32

Review of Cost-Effectiveness Analysis of Medical Treatment For Myocardial Infarction  

UK PubMed Central (United Kingdom)

Objectives:Myocardial infarction (MI) is a leading cause of death in both the industrialized and developing countries globally. The economic evaluation of MI is undertaken...Full Text Available

2011-04-01

33

Arterial and Venous Thrombosis in Cancer Patients  

UK PubMed Central (United Kingdom)

The most frequent ultimate cause of death is myocardial arrest. In many cases this is due to myocardial hypoxia, generally arising from failure of the coronary macro- and microcirculation to deliver...Full Text Available

34

RangerMaster{trademark}: Real-time pattern recognition software for in-field analysis of radiation sources  

Energy Technology Data Exchange (ETDEWEB)

RangerMaster{trademark} is the embedded firmware for Quantrad Sensor`s integrated nuclear instrument package, the Ranger{trademark}. The Ranger{trademark}, which is both a gamma-ray and neutron detection system, was originally developed at Los Alamos National Laboratory for in situ surveys at the Plutonium Facility to confirm the presence of nuclear materials. The new RangerMaster{trademark} software expands the library of isotopes and simplifies the operation of the instrument by providing an easy mode suitable for untrained operators. The expanded library of the Ranger{trademark} now includes medical isotopes {sup 99}Tc, {sup 201}Tl, {sup 111}In, {sup 67}Ga, {sup 133}Xe, {sup 103}Pa, and {sup 131}I; industrial isotopes {sup 241}Am, {sup 57}Co, {sup 133}Ba, {sup 137}Cs, {sup 40}K, {sup 60}Co, {sup 232}Th, {sup 226}Ra, and {sup 207}Bi; and nuclear materials {sup 235}U, {sup 238}U, {sup 233}U, and {sup 239}Pu. To accomplish isotopic ...

1998-12-31

35

Measurement of relative L X-ray intensity ratio following radioactive decay and photoionization  

Energy Technology Data Exchange (ETDEWEB)

The measurements of the L X-ray intensity ratio I(L{alpha})/I(L{beta}), I(L{alpha})/I(L{gamma}), I(L{alpha})/I(L{iota}), I(L{beta})/I(L{gamma}) and I(L{iota})/I(L{gamma}) for elements Dy, Ho, Yb, W, Hg, Tl and Pb were experimentally determined both by photon excitation, in which 59.5 keV {gamma}-rays from a filtered radioisotope {sup 241}Am was used, and by the radioactive decay of {sup 160}Tb, {sup 160}Er, {sup 173}Lu, {sup 182}Re, {sup 201}Tl, {sup 203}Pb and {sup 207}Bi. L X-rays emitted by samples were counted by a Si(Li) detector with resolution 160 eV at 5.9 keV. Obtained values were compared with the calculated theoretical values. Theoretical values of the I(L{alpha}/L{beta}), I(L{alpha}/L{gamma}), I(L{alpha}/L{iota}), I(L{beta}/L{gamma}) and I(L{iota}/L{gamma}) intensity ratios were calculated using theoretically tabulated values of subshell photoionization cross-section, fluorescence yield, fractional X-ray emission rates, ...

2008-05-22

36

Dose coefficients for intakes of radionuclides via contaminated wounds.  

Science.gov (United States)

The NCRP Wound Model, which describes the retention of selected radionuclides at the site of a contaminated wound and their uptake into the transfer compartment, has been combined with the ICRP element-specific systemic models for those radionuclides to derive dose coefficients for intakes via contaminated wounds. These coefficients can be used to generate derived regulatory guidance (i.e., the activity in a wound that would result in an effective dose of 20 or 50 mSv, or in some cases, a organ-equivalent dose of 500 mSv) and clinical decision guidance (i.e., activity levels that would indicate the need for consideration of medical intervention to remove activity from the wound site, administration of decorporation therapy or both). Data are provided for 38 radionuclides commonly encountered in various activities such as nuclear weapons, fuel fabrication or recycling, waste disposal, medicine, research, and nuclear power. These include 3H, 14C, 32P, 35S, 59Fe, 57,58,60Co, 85,89,90Sr, ...

2011-05-01

37

Distributions of "1"3"7Cs, "2"0"1T1, "2"0"3Hg, "2"0"3Pb and "5"7Co in a rat hepatoma model. Comparison with "6"7Ga  

International Nuclear Information System (INIS)

The distribution of carrier-free "2"0"3Pb-acetate, "2"0"3HgCl_2, "5"7Cocl_2, "1"3"7CsCl and "2"0"1TlCl was investigated in rats bearing thigh-implanted Morris 7777 hepatomas. Viable and nonviable tumor tissue was collected in order to determine the relative affinities of the radiopharmaceutical for these tissues. The animals were sacrificed at 4, 24, 48, 72 and 96 hrs following intravenous injection. Washout of the radioisotope from the viable tumor tissue was rapid, the maximum concentration being reached on or before 4 hrs following injection. In contrast, residual activity within the nonviable tumor tissue decreased much more slowly and in some cases even increased with time. Viable tumor-to-muscle and nonvialbe tumor-to-muscle ratios for "2"0"3Pb, "2"0"3Hg and "5"7Co were comparable to the analogous ratios reported for "6"7Ga. However, none of these isotopes approached "6"7Ga as a potential tumor imaging agent because the large ratios were the result of low muscle uptake rather ...

38

Cellular dosimetry: Absorbed fractions for monoenergetic electron and alpha particle sources and S-values for radionuclides uniformly distributed in different cell compartments  

Energy Technology Data Exchange (ETDEWEB)

The importance of cellular dosimetry in both diagnostic and therapeutic nuclear medicine is becoming increasingly recognized. Experimental range-energy relations for electrons and alpha particles, along with derived geometric reduction factors, are used to calculate cellular absorbed fractions for these radiations. The resulting absorbed fractions are employed to calculate cellular S-values for several radionuclides. Cellular absorbed fractions for monoenergetic electron sources with energies ranging from 0.1 keV to 1 MeV, distributed uniformly in the source region, are calculated for several target {l_arrow} source combinations including cell{l_arrow}cell, cell{l_arrow}cell surface, nucleus{l_arrow}nucleus, nucleus {l_arrow}cytoplasm and nucleus {l_arrow}cell surface. Similar data are also provided for monoenergetic alpha particle sources with energies ranging from 3 to 10 MeV. S-values are also conveniently tabulated for {sup 32}P, {sup 35}S, {sup 86}Rb, {sup 89}Sr, {sup 90}Y, {sup ...

1994-02-01

39

Myocardial metabolic regulation through peroxisome proliferator-activated receptor alpha after myocardial infarction  

UK PubMed Central (United Kingdom)

Although peroxisome proliferator-activated receptor alpha (PPARα) is closely associated with myocardial fatty acid metabolism, the pathophysiological role of PPARα in myocardial infarction...Full Text Available

2003-01-01

40

Localization of "2"0"3Pb-chloride in myocardial infarction  

International Nuclear Information System (INIS)

... AND NUCLEAR MEDICINE biological localization cardiovascular diseases

42

Ionizing radiation hardening procedure of CCD's  

International Nuclear Information System (INIS)

The procedure of charge-coupled devices (CCD) are investigated by using MOS capacitors for enhancing their ionizing radiation tolerance. Authors have found that the gate oxidation temperature, thickness of SiO_2 gate insulator and high temperature processes after gate oxidation are crucial for determining the radiation tolerance of the devices, and proposed to decrease the thickness of gate insulator, perform gate oxidation at 1000 deg C by means of dry oxidation and minimize the number of high temperature procedure steps after gate oxidation. All stated above is a necessary preparation for priducing radiation hardened charge-coupled devices.

43

Use of clopidogrel in the reduction of myocardial damage during percutaneous coronary intervention  

UK PubMed Central (United Kingdom)

It is estimated that approximately a quarter of patients undergoing coronary intervention may have significant post-procedural creatinine (CK)/creatinine kinase myocardial band (CK-MB) elevations and...Full Text Available

2009-01-01

44

Trial of early nifedipine in acute myocardial infarction: the Trent study.  

UK PubMed Central (United Kingdom)

Over 30 months 9292 consecutive patients admitted to nine coronary care units with suspected myocardial infarction were considered for admission to a randomised double blind study comparing the effect...Full Text Available

1986-11-08

45

The zebrafish heart regenerates after cryoinjury-induced myocardial infarction  

UK PubMed Central (United Kingdom)

BackgroundIn humans, myocardial infarction is characterized by irreversible loss of heart tissue, which becomes replaced with a fibrous scar. By contrast, teleost fish and urodele...Full Text Available

46

The Trade-Off between Costs and Outcomes: The Case of Acute Myocardial Infarction  

UK PubMed Central (United Kingdom)

ObjectiveTo investigate and to quantify the relationship between hospital costs and health outcomes for patients with acute myocardial infarction (AMI) in Veterans Health Administration...Full Text Available

2010-12-01

47

Routine invasive management after fibrinolysis in patients with ST-elevation myocardial infarction: a systematic review of randomized clinical trials  

UK PubMed Central (United Kingdom)

BackgroundPatients with ST-elevation myocardial infarction (STEMI) treated with fibrinolysis are increasingly, and ever earlier, referred for routine coronary angiography and where...Full Text Available

48

Motor Vehicle Licences and Myocardial Infarction  

UK PubMed Central (United Kingdom)

Health standards for truck drivers are higher than those for the general motoring public, particularly concerning the need to restrict driving following recovery from a myocardial infarction. An analysis...Full Text Available

1984-12-01

49

Identification of Cardiac Myosin-binding Protein C as a Candidate Biomarker of Myocardial Infarction by Proteomics Analysis*  

UK PubMed Central (United Kingdom)

Acute myocardial infarction (AMI) is a common cause of death for which effective treatments are available provided that diagnosis is rapid. The current diagnostic gold standards are circulating cardiac...Full Text Available

2009-12-01

50

Efficacy and Safety of Low-Molecular-Weight Heparins As An Adjunct to Thrombolysis in Acute ST-Elevation Myocardial Infarction  

UK PubMed Central (United Kingdom)

A 48-hour course of intravenous unfractionated heparin (UFH) is the standard of treatment in conjunction with fibrin-specific thrombolysis in ST-elevation myocardial infarction (STEMI). In recent trials,...Full Text Available

2008-02-01

51

Effects of norepinephrine infusion on myocardial high-energy phosphate content and turnover in the living rat.  

UK PubMed Central (United Kingdom)

Using 31P-nuclear magnetic resonance, we studied the relationship between myocardial high-energy phosphate content and flux values for the creatine kinase reaction in the living rat under inotropic...Full Text Available

1987-06-01

52

Anatomical Reasons for the Discrepancies in Atrioventricular Block after Inferior Myocardial Infarction with and without Right Ventricular Involvement  

UK PubMed Central (United Kingdom)

The incidence of arrhythmias after acute myocardial infarction of the inferior wall varies with the affected segment and increases when there is right ventricular involvement. This paper provides a...Full Text Available

2009-01-01

53

A New Efficient Method of Topical Cooling and Rewarming of the Myocardium  

UK PubMed Central (United Kingdom)

Profound myocardial hypothermia (below 17° C, and more often around 12° C) is imperative in myocardial protection while the aorta is cross-clamped. Based on our experience in...Full Text Available

1985-12-01

55

Transesophageal echo to help percutaneous closure of ventricular septal defect post acute myocardial infarction  

British Library Electronic Table of Contents (United Kingdom)

Ventricular septal defect after acute myocardial infarction (AMI) is a complication associated with poor outcome in the absence of intervention. We report a case of successful TEE guided transcatheter closure of a post myocardial infarction (MI) ventricular septal defect (VSD) with an Amplatzer occluder in a 79 years old male with cardiogenic shock.

2011-01-01

56

Detection of acute myocardial infarction in spontaneously hypertensive rats by /sup 99m/Tc-Pyrrolidino methyl tetracycline  

Energy Technology Data Exchange (ETDEWEB)

The myocardial infarct induced by isoproterenol in spontaneously hypertensive rats accumulates higher activities of /sup 99/sup(m)Tc-PM tetracycline compared with the cardiac infarct in normotensive rats caused by the same method. The isoproterenol model of the myocardial necrosis was induced in intact rats without opening the thorax and is a convenient method for experimental radioisotope studies.

1983-01-01

57

The opening of the two pores of the Hv1 voltage-gated proton channel is tuned by cooperativity  

UK PubMed Central (United Kingdom)

SUMMARYIn voltage-gated sodium, potassium, and calcium channels the functions of ion conduction and voltage sensing are performed by two distinct structural units: the pore domain...Full Text Available

2010-01-01

58

Pore region of TRPV3 ion channel is specifically required for heat-activation  

UK PubMed Central (United Kingdom)

Ion-channels can be activated (gated) by a variety of stimuli including chemicals, voltage, mechanical force or temperature. Whereas molecular mechanisms of ion-channel gating by chemicals and...Full Text Available

2008-09-01

59

Oxidation of an engineered pore cysteine locks a voltage-gated K+ channel in a nonconducting state.  

UK PubMed Central (United Kingdom)

We report the use of cysteine-substituted mutants in conjunction with in situ oxidation to determine the physical proximity of a pair of engineered cysteines in the pore region of the voltage-gated...Full Text Available

1996-12-01

60

Formation kinetics and work function tuning of Pd_2Si fully silicided metal gate  

International Nuclear Information System (INIS)

The formation kinetics of Pd_2Si for fully silicided (FUSI) gate formation and the work function tuning of a Pd_2Si FUSI gate by impurity predoping were investigated. It has been found that the morphology and phase of a formed FUSI layer depend not only on the silicidation annealing temperature but also on the heating ramp-up rate and the presence of impurities. Fast ramp-up annealing was necessary to avoid defect formation, such as voids in the silicide film at the oxide interface, and to obtain a homogeneous silicide film containing only Pd_2Si phase. The most severe effect on the silicidation reaction, that is the increase in defect formation, was brought about by As predoping. The work function of the Pd_2Si FUSI gate was modulated by impurity pileup at the Pd_2Si/SiO_2 interface, as in the case of the NiSi FUSI gate. However, the work function shifted in the opposite direction to that of the NiSi ...

2007-04-01

61

Dimeric subunit stoichiometry of the human voltage-dependent proton channel Hv1  

UK PubMed Central (United Kingdom)

In voltage-gated Na+, K+, and Ca2+ channels, four voltage-sensor domains operate on a central pore domain in response to membrane voltage. In contrast, the voltage-gated...Full Text Available

2008-06-03

62

Magnetic Tape Pulse Width to Digital Convertor.  

Science.gov (United States)

... This is achieved by the use of a unique logic circuit employing a plurality of flip-flop devices, multivibrators and AND gates. ...

1976-12-07

63

Handbook Prefered Circuits Navy Aeronautical Electronic ...  

Science.gov (United States)

... 9. Delay Circuits ----- N9-i 10. Main Gate Multivibrators ----- NI0-I 11. ...

1959-04-01

64

Serial Intravascular Ultrasound Analysis of the Impact of Myocardial Bridge on Neointimal Proliferation After Coronary Stenting in Patients with Acute Myocardial Infarction  

British Library Electronic Table of Contents (United Kingdom)

Background: Mechanisms underlying the association between myocardial bridge (MB)-stenting and in-stent restenosis (ISR) are still unclear. Objective: To assess the impact of MB on ISR using intravascular ultrasound (IVUS). Methods: In the Harmonizing Outcomes with Revascularization and Stents in Acute Myocardial Infarction (HORIZONS-AMI) trial, 100 left anterior descending artery (LAD) culprit lesions (79 treated with paclitaxel-eluting stents [PES] and 21 treated with bare metal stents) were imaged with serial IVUS immediately postprocedure and at 13 months. Results: At baseline the LAD stent extended into the MB segment beyond the culprit lesion in seven patients (MB-stent group). In the remaining 93 patients the LAD stent was implanted only in the culprit lesion without extending into t...

2010-01-01

65

Myocardial imaging in patients with Kawasaki disease. Exercise stress imaging and serial studies  

Energy Technology Data Exchange (ETDEWEB)

Thallium-201 myocardial imaging was performed in 80 children with coronary arterial lesions due to Kawasaki disease in order to assess the value of serial and exercise myocardial imagings. In eight of these children, abnormalities of the image were noted. Twenty children had serial thallium studies with an interval of three to 18 months, and five of these showed changes in the image including appearance of a new perfusion defect in one patient and improvement of perfusion defects in four. These changes of the myocardial image were correlated well with coronary angiographic findings obtained within a few days of the isotope studies. It was noted that the changes of the myocardial image were more frequently observed at relatively recent period recovered from Kawasaki disease. Exercise myocardial imaging using a bicycle ergometer was performed in eight children with coronary arterial ...

1982-06-01

66

Cardioprotection conferred by exercise training is blunted by blockade of the opioid system  

UK PubMed Central (United Kingdom)

OBJECTIVES:To investigate the effect of opioid receptor blockade on the myocardial protection conferred by chronic exercise and to compare exercise training with different strategies...Full Text Available

2011-01-01

67

Cardiac Enzymes, Renal Failure and Renal Transplantation  

UK PubMed Central (United Kingdom)

Diagnostic accuracy of the currently available serum markers of cardiac injury, such as myoglobin, creatine kinase and its myocardial isoform, are altered in patients with renal failure. It is shown...Full Text Available

2006-03-01

68

Microcrystalline-Si thin-film transistors formed by using palladium silicided source/drain contact electrode  

British Library Electronic Table of Contents (United Kingdom)

Microcrystalline-Si thin-film transistors (?C-Si TFTs) formed by using the source/drain contact electrode of self-aligned palladium silicide have been investigated. Both the self-aligned palladium silicided scheme and the previous top-gate staggered structure employ two-mask process steps for fabricating ?C-Si TFTs. However, the self-aligned palladium silicided scheme would cause better device characteristics than the top-gate staggered structure, primarily due to more carrier tunneling. For a gate length of 2 ?m, as compared to the top-gate staggered scheme, this silicided scheme can result in a 40% improvement of on-state current. In addition, as the gate length is reduced to 1 ?m, considerable short-channel effect is caused for both the device schemes.

2010-01-01

69

A Simple Scheme for Realizing a Multiqubit Controlled-Phase Gate Through a Resonant Interaction of Three-Level Atoms with a Single-Mode Cavity  

International Nuclear Information System (INIS)

A very simple theoretical scheme is proposed to implement two- and three-qubit controlled-phase gates firstly only using a single resonant interaction between ladder-type three-level atoms and the single-mode cavity. In the presented protocol, the quantum information is encoded on the stable ground states of the atoms (as the controlling qubits) and the zero- and one-photon Fock states of cavity-field (as the target qubit). Under the influence of the atomic spontaneous emission, the decay of the cavity-mode, and deviation of the coupling strength, the three-qubit controlled-phase gate may have a comparatively high fidelity. The experimental feasibility of controlled-phase gate and the case that is extended to realize N-qubit controlled-phase gate are also discussed. (general)

2010-03-15

70

Disagreements between central clinical events committee and site investigator assessments of myocardial infarction endpoints in an international clinical trial: review of the PURSUIT study  

UK PubMed Central (United Kingdom)

BackgroundLimited information has been published regarding how specific processes for event adjudication can affect event rates in trials. We reviewed nonfatal myocardial infarctions...Full Text Available

2001-01-01

71

Diagnosis of early human myocardial ischemic damage with electron probe microanalysis  

Energy Technology Data Exchange (ETDEWEB)

We determined the Na/K x-ray intensity ratio in frozen sections of myocardial tissues obtained at autopsy from patients who died from various causes, using electron probe analysis. We have been able to distinguish between the ischemically injured and normal cells. The method is simple, fast, and dependable even when the duration of ischemia is only 30 minutes.

1983-03-01

72

Associations of major bleeding and myocardial infarction with the incidence and timing of mortality in patients presenting with non-ST-elevation acute coronary syndromes: a risk model from the ACUITY trial  

UK PubMed Central (United Kingdom)

AimsTo evaluate the associations of myocardial infarction (MI) and major bleeding with 1-year mortality. Both MI and major bleeding predict 1-year mortality in patients presenting...Full Text Available

2009-06-01

73

The accuracy and reverse effects of thallium myocardial SPECT using adenosine triphosphate loading in the diagnosis of coronary artery disease. Comparison with other loading methods semiquantitatively  

Energy Technology Data Exchange (ETDEWEB)

The adverse effects and diagnostic accuracy of thallium-201 myocardial SPECT after intravenous infusion of adenosine triphosphate (ATP) were studied and compared with SPECT examinations with other type of loading. The subjects of the study were 147 patients with or without coronary artery disease, who underwent some type of loading SPECT and coronary arteriography (CAG) within 30 days. Myocardial ischemia was evaluated qualitatively in SPECT and was compared with CAG for the diagnostic accuracy of coronary artery disease. The degree of myocardial uptake defect was also calculated semiquantitatively using visual scoring method and compared with coronary artery severity score. The adverse effects occurred in 46.7% of ATP loading SPECT which was more frequent that DIP loading SPECT, but all of them were transient and mild. As for the diagnostic ability the ATP loading SPECT was as effective as other type of loading in ...

1999-09-01

74

Time-resolved reflectance studies of silicon during laser thermal processing of amorphous silicon gates on ultrathin gate oxides  

International Nuclear Information System (INIS)

In this paper, we report the systematic investigation on the melt characteristics of silicon during laser thermal processing (LTP) of amorphous silicon (a-Si) gates on ultrathin gate oxides. LTP is used to reduce the gate depletion effect in advanced semiconductor devices. The influence of implantation-induced damage and chemical inhomogeneities on the melt behavior of ion-implanted a-Si is studied using in situ time-resolved reflectance (TRR) measurements and ex situ secondary ion mass spectrometry. The results from TRR measurements indicate the presence of a buried melt for a-Si implanted with B"+ at a subamorphizing dose. In contrast, such a melt behavior is not observed during LTP of undoped a-Si and a-Si implanted with As"+ at an amorphizing dose. We attribute the marked difference in the melt characteristics to the competitive effects between compositional inhomogeneities and the extent of amorphization in the a-Si ...

2004-06-01

75

Selecting parameters of powered supports for junctions of working faces and gate roads based on hydraulics  

Energy Technology Data Exchange (ETDEWEB)

Evaluates experiments aimed at selecting optimum design and technical specifications of a support system for junctions of gate roads and longwall faces mined by shearer loaders and powered supports. A set of supports used at a junction of a working face and a gate road consisted of 2 supports (each made up of a roof bar and two hydraulic props). Roof bar length ranged from 4.0 to 5.5 m and from 7.0 to 9.0 m respectively. The support roof bars were parallel to the longitudinal axis of a gate road. Stress distribution in strata surrounding a junction of a working face and a gate road was analyzed. The finite element method was used. Convergence of the roof and the floor of a gate road depending on support yield strength and distance from a measuring point to the supports was analyzed. Recommendations are made for optimum yield strength of the supports. Nomograms for selecting optimum ...

1993-01-01

76

Study of total ionizing dose radiation effects on nitride/oxide stack gate MOS capacitor  

International Nuclear Information System (INIS)

The aim of this paper is to investigate the total ionizing dose (TID) radiation effects on MOS capacitor with nitride/oxide stack gate. The stack gate MOS capacitors are fabricated with 20 nm oxide, 40 nm nitride or 110 nm nitride respectively. Through the analysis of CV curve of the irradiation capacitors, it is found that the degradation of the CV curve is due to a significant increase of interface traps and somewhat smaller oxide charge. It is also shown that the thicker of the nitride, more interface traps and oxide charge will be occurred. (authors)

2008-07-01

77

Development of an injection molding tool for complex microfluidic geometries  

British Library Electronic Table of Contents (United Kingdom)

This paper will track the design and results of an injection molding tool developed to manufacture microfluidic chips. The mold design and injection molding process was complicated by the presence of integrated capillary fluidic interconnects. We determined that design of the runner and gate system responsible for delivering molten plastic to the cavity had a significant impact on the quality of parts produced by the mold and the size of the process window. Numerical results confirm our findings that reducing gate lengths and increasing part thickness dramatically improved the filling profile and lowered injection pressures by 37%. Finally, the influence of gate location on part shrinkage is analyzed and discussed.

2011-01-01

78

Three-terminal electric transport measurements on gold nano-particles combined with ex situ TEM inspection  

International Nuclear Information System (INIS)

We have fabricated nanometer-spaced electrodes on electron-transparent silicon nitride membranes. A thin Cr/Au layer is evaporated on the backside of the membrane which serves as a gate electrode. Using these devices, we have performed three-terminal electron transport measurements on gold nano-particles at liquid helium temperature. Coulomb Blockade features have been observed and the capacitance to the gate has been extracted. After transport measurements, the Cr/Au back gate is removed and the devices are inspected with a transmission-electron microscope (TEM). TEM inspection reveals the presence of a few nano-particles in the nanogap, which is in agreement with the transport measurements. In addition, the nano-particle size as observed by TEM coincides with the one estimated from the gate capacitance value.

2009-10-14

79

Quantum Information Processing Using Local Control of ...  

Science.gov (United States)

... The insu- lation between gate and nanowire is the high-k dielectric HfO2, deposited by atomic layer depo- sition (ALD). ...

2006-12-31

80

Photonic Devices and Systems for Optical Signal Processing  

Science.gov (United States)

... lasers, model switched optical memory elements ... Optical RS flip flop, Acousto-optic switches. ... FLOP CIRCUITS, OPTICAL SWITCHING, NOR GATES ...

1993-08-01

81

Percolation, renormalization, and quantum computing with non-deterministic gates  

Energy Technology Data Exchange (ETDEWEB)

We apply a notion of static renormalization to the preparation of cluster states for quantum computing, exploiting ideas from percolation theory. Such a strategy yields a novel way to cope with the randomness of non-deterministic quantum gates. This is most relevant in the context of linear optical architectures, where probabilistic gates are inevitable. We demonstrate how to efficiently construct cluster states without the need for rerouting, thereby avoiding a massive amount of feed-forward and conditional dynamics, and furthermore show that except for a single layer of fusion measurements during the preparation, all further measurements can be shifted to the final adapted single qubit measurements. Remarkably, the cluster state preparation is achieved using essentially the same scaling in resources as if deterministic gates were available. Further, techniques to reduce the size of the required resource states will be ...

2007-07-01

82

Fabrication of self-aligned aluminum gate polysilicon thin-film transistors using low-temperature crystallization process  

Energy Technology Data Exchange (ETDEWEB)

The performance of scanning driver circuits fabricated with self-aligned aluminum gate polysilicon thin-film transistors (TFT's) is demonstrated. After the gate electrode patterning, the fabrication process temperature is kept below 400degC to enable the use of aluminum gate electrodes. The low-temperature crystallization phenomenon, which occurs when protons are implanted simultaneously with boron or phosphorus dopants, is employed to eliminate the 600degC activation-annealing process. A maximum clock frequency of about 2.0 MHz is achieved when the driver operating voltage is 24 V and the TFT channel length is 12 [mu]m. (author).

1994-01-01

83

Fabrication of self-aligned aluminum gate polysilicon thin-film transistors using low-temperature crystallization process  

International Nuclear Information System (INIS)

The performance of scanning driver circuits fabricated with self-aligned aluminum gate polysilicon thin-film transistors (TFT's) is demonstrated. After the gate electrode patterning, the fabrication process temperature is kept below 400degC to enable the use of aluminum gate electrodes. The low-temperature crystallization phenomenon, which occurs when protons are implanted simultaneously with boron or phosphorus dopants, is employed to eliminate the 600degC activation-annealing process. A maximum clock frequency of about 2.0 MHz is achieved when the driver operating voltage is 24 V and the TFT channel length is 12 #mu#m. (author).

84

Directory of NSF-Supported UFE Projects  

Science.gov (United States)

... .13 Teaching the Materials Science, Engineering, and Field Aspects of Concrete ... Gate Arrays. . . . . . . . . . . . . . .15 Materials Science Concepts for Introductory Courses in ...

85

Defense.gov News Article: Gates, Mullen Urge Participation in ...  

Science.gov (United States)

... No where on an OER or an NCOER is there a box to be checked ... Chaplains will have a issues with it as far as marriage counseling or other issues ...

87

Successful transcatheter coil embolization of coronary artery to left ventricular fistula associated with absent pulmonary valve with tricuspid atresia in early infancy.  

Science.gov (United States)

Transcatheter coil embolization for coronary artery to left ventricular fistula was successfully performed in a neonate. At 30 weeks' gestation, fetal echocardiography showed a hypoplastic right ventricle with intact ventricular septum, absent pulmonary valve, tricuspid atresia, and marked distension of the right coronary artery. After birth, the neonate had congestive heart failure and the electrocardiogram showed myocardial ischemic changes in the left ventricular area. Aortography showed a dilated right coronary artery arising from the ascending aorta and draining into the left ventricle. Transcatheter coil embolization was carried out on the 9th day after birth. Since the procedure, no myocardial ischemic changes have been detected. Transcatheter coil embolization is a useful therapy for coronary artery fistula associated with myocardial ischemia. PMID:15564713

2004-12-01

88

Plasma carotenoids and risk of acute myocardial infarction in the Singapore Chinese Health Study  

British Library Electronic Table of Contents (United Kingdom)

Background and aimModification of low-density lipoprotein due to oxidative stress is essential in the development of coronary atherosclerosis. Data of specific carotenoids except b-carotene on cardioprotective effects in humans are limited. Methods and resultsThis study examined the associations between plasma concentrations of specific carotenoids and incidence of acute myocardial infarction. The study included 280 incident cases of acute myocardial infarction and 560 matched controls nested within the Singapore Chinese Health Study, a prospective cohort of 63,257 Chinese men and women aged 45-74 years old enrolled in 1993-1998 in Singapore. Retinol and carotenoids in prediagnostic plasma were quantified using high-performance liquid chromatography. High levels of plasma b-cryptoxanthin a...

2011-01-01

89

PET and MRI in cardiac imaging: from validation studies to integrated applications  

International Nuclear Information System (INIS)

Positron emission tomography (PET) is the gold standard for non-invasive assessment of myocardial viability and allows accurate detection of coronary artery disease by assessment of myocardial perfusion. Magnetic resonance imaging (MRI) provides high resolution anatomical images that allow accurate evaluation of ventricular structure and function together with detection of myocardial infarction. Potential hybrid PET/MR tomography may potentially facilitate the combination of information from these imaging modalities in cardiology. Furthermore, the combination of anatomical MRI images with the high sensitivity of PET for detecting molecular targets may extent the application of these modalities to the characterization of atherosclerotic plaques and to the evaluation of angiogenetic or stem cell therapies, for example. This article reviews studies using MRI and PET in parallel to compare their performance in cardiac ...

2009-03-01

90

Correlation of myocardial TC-99m-MIBI perfusion SPECT with coronary angiography in Namazi hospital  

International Nuclear Information System (INIS)

Coronary heart disease is the leading cause of death specially among elderly. Coronary angiography is the best diagnostic method in the patients, but is unfortunately an invasive procedure with its inherent risks. Myocardial perfusion scan is a noninvasive and sensitive method for evaluation of Coronary artery disease and is suggested by many investigators in recent years. In this study, 64 patients who had a Tc99m-MIBI SPECT myocardial perfusion study at our department, underwent coronary angiography within 4 months. Correlation of the methods revealed that SPECT Tc99m -MIBI had a high sensitivity and specificity in our hand, which is comparable with international findings.

2004-04-27

91

The Aging Heart and Post-Infarction Left Ventricular Remodeling  

UK PubMed Central (United Kingdom)

Aging is a risk factor for heart failure, which is a leading cause of death world-wide. Elderly patients are more likely than young patients to experience a myocardial infarction (MI) and are...Full Text Available

2010-12-28

92

Spontaneous coronary artery dissection in the postpartum period: association with antiphospholipid antibody  

UK PubMed Central (United Kingdom)

Spontaneous coronary artery dissection (SCAD) is an extremely uncommon cause of myocardial infarction, occurring predominantly in women during or after pregnancy. The exact aetiology...Full Text Available

2004-09-01

93

Selective endothelin A-receptor blockade attenuates coronary microvascular dysfunction after coronary stenting in patients with type 2 diabetes  

UK PubMed Central (United Kingdom)

Background:Endothelin-1 may be involved in the development of diabetic microangiopathy. We studied the effect of endothelin-1 blockade on myocardial microcirculation during coronary...Full Text Available

2009-01-01

94

Segmentation of Myocardial Boundaries in Tagged Cardiac MRI Using Active Contours: A Gradient-Based Approach Integrating Texture Analysis  

UK PubMed Central (United Kingdom)

The noninvasive assessment of cardiac function is of first importance for the diagnosis of cardiovascular diseases. Among all medical scanners only a few enables radiologists to evaluate the local cardiac...Full Text Available

2009-01-01

95

Relation between regional and global systolic function in patients with ischemic cardiomyopathy after ?-Blocker therapy or revascularization  

UK PubMed Central (United Kingdom)

BackgroundTo assess the relationship between improved regional and global myocardial function in patients with ischemic cardiomyopathy in response to β-blocker therapy or...Full Text Available

96

Recent US Patterns and Predictors of Prevalent Diabetes among Acute Myocardial Infarction Patients  

UK PubMed Central (United Kingdom)

Background. Diabetes mellitus (DM) confers high vascular risk and is a growing national epidemic. We assessed clinical characteristics and prevalence of diagnosed DM among patients...Full Text Available

97

Pharmacological Prevention of Peri-, and Post-Procedural Myocardial Injury in Percutaneous Coronary Intervention  

UK PubMed Central (United Kingdom)

In recent years, percutaneous coronary intervention (PCI) has become a well-established technique for the treatment of coronary artery disease. PCI improves symptoms in patients with coronary artery...Full Text Available

2008-08-01

98

Percutaneous Management of a Long Saphenous Vein Graft Aneurysm: A Case Report and Review of Literature  

UK PubMed Central (United Kingdom)

Aneurysms of saphenous vein grafts are rare but can result in complications such as myocardial infarction or death. Percutaneous treatment has included a variety of approaches, including covered stents....Full Text Available

2009-01-01

99

Normal Coronary Artery Patient Presenting with Left Ventricular Aneurysm  

UK PubMed Central (United Kingdom)

Left ventricular aneurysm (LVA) is one of the most important complications of myocardial infarction LVA is strictly defined as a distinct area of abnormal left ventricular diastolic contour with systolic...Full Text Available

2011-01-01

101

Management of patients with unstable angina/non-ST-elevation myocardial infarction: a critical review of the 2007 ACC/AHA guidelines  

UK PubMed Central (United Kingdom)

Background:In 2007, the American College of Cardiology/American Heart Association (ACC/AHA) published new guidelines for the diagnosis and management of patients with unstable angina/non-ST...Full Text Available

2009-04-01

102

MRI Findings of Pericardial Fat Necrosis: Case Report  

UK PubMed Central (United Kingdom)

Pericardial fat necrosis is an infrequent cause of acute chest pain and this can mimic acute myocardial infarction and acute pericarditis. We describe here a patient with the magnetic resonance imaging...Full Text Available

2011-05-01

103

Lipotoxic heart disease in obese rats: Implications for human obesity  

UK PubMed Central (United Kingdom)

To determine the mechanism of the cardiac dilatation and reduced contractility of obese Zucker Diabetic Fatty rats, myocardial triacylglycerol (TG) was assayed chemically and morphologically. TG was...Full Text Available

2000-02-15

104

Left Main Stent Thrombosis Complicated by Eptifibatide-Induced Acute Thrombocytopenia  

UK PubMed Central (United Kingdom)

A 57-year-old man with a history of coronary artery disease and placement of an implantable cardioverter-defibrillator presented at our emergency room with an anterior ST-elevation myocardial infarction....Full Text Available

2011-01-01

105

Intravascular ultrasound to guide the management of intracoronary thrombus: a Case Report  

UK PubMed Central (United Kingdom)

Percutaneous coronary intervention can be associated with distal embolization of thrombotic material causing myocardial necrosis and infarction.We discuss the role of intravascular imaging to...Full Text Available

106

Features and Outcomes In Utero and after Birth of Fetuses with Myocardial Disease  

UK PubMed Central (United Kingdom)

Objectives. Ninety-one fetuses with dilated or hypertrophic cardiomyopathy (DCM, HCM) and myocarditis were studied. Results. Group 1 “DCM”...Full Text Available

2010-01-01

107

Elevated Cardiac Troponin I in Sepsis and Septic Shock: No Evidence for Thrombus Associated Myocardial Necrosis  

UK PubMed Central (United Kingdom)

BackgroundElevated cardiac troponin I (cTnI) is frequently observed in patients with severe sepsis and septic shock. However, the mechanisms underlying cTnI release in these patients...Full Text Available

108

Dietary Glycaemic Index, Dietary Glycaemic Load, and Incidence of Myocardial Infarction in Women  

UK PubMed Central (United Kingdom)

The association of dietary glycaemic index (GI) and glycaemic load (GL) with cardiovascular diseases has been examined in several populations with varying results. We tested the hypothesis that...Full Text Available

2010-04-01

109

Clinical utility of tissue Doppler imaging in patients with acute myocardial infarction complicated by cardiogenic shock  

UK PubMed Central (United Kingdom)

BackgroundEchocardiography is widely used in the management of patients with cardiogenic shock (CS). Left ventricular ejection fraction (EF) has been shown to be an independent predictor...Full Text Available

110

Clinical Application of Ischemic Preconditioning in the Elderly  

UK PubMed Central (United Kingdom)

A mild stress such as brief ischemic episodes may protect the heart from a successive and more prolonged myocardial ischemia (ischemic preconditioning). This phenomenon is considered a typical “hormetic...Full Text Available

111

Anxiety in Patients with Cardiac Disease.  

Science.gov (United States)

Anxiety may cause adverse outcomes through physiologic pathways in patients with cardiac disease. The purpose of this dissertation was to investigate anxiety and its correlates in persons with acute myocardial infarction (AMI) and heart failure (HF). The ...

2005-01-01

112

Analysis of myocardial time-activity curves of /sup 123/I-heptadecanoic acid. Pt. 1. Curve fitting  

Energy Technology Data Exchange (ETDEWEB)

Myocardial time-activity curves can be described by two or more parameters. To establish the optimal curve fitting method 33 myocardial time-activity curves were analyzed with different curve fitting methods: monoexponential, biexponential and monoexponential plus constant. A background correction was not applied. Biexponential curve fitting resulted in redundancy of parameters. Optimal curve fitting was obtained with monoexponential plus constant. The constant represents the background activity together with the stores radiolabelled lipids and the half-time value represents the wash-out of radioiodide from the myocardium. A strong relation was found between the constant and the half-time value: small errors in the determination of the constant (background activity) resulted in considerable errors of the half-time value. It is concluded that optimal analysis of a myocardial time-activity curve can be performed with a ...

1987-12-01

113

Access to Cardiac Interventional Services in Alabama and Mississippi: A Geographical Information System Analysis  

UK PubMed Central (United Kingdom)

ObjectiveThe objective of this study was to determine the contribution of distance to hospitals with cardiac interventional services (CIS) to county age-adjusted myocardial infarction...Full Text Available

114

MOS device chemical response reversal with temperature  

British Library Electronic Table of Contents (United Kingdom)

Biased above threshold (VT), pulsed photocurrent (u) measurements on windowed silicon Pd gate MOS capacitors are shifted (DV) negatively by H2/N2, whereas Au gates shift positively under NO2/air. Below VT, the shifts are reversed by adjustments of interface state population. Minor temperature increases may coax the device from inversion to depletion, inducing sign reversal of the chemical response.

2010-01-01

115

Influence of MeV electron irradiation on the properties of by ion implantation hydrogenated polysilicon TFTs  

Energy Technology Data Exchange (ETDEWEB)

The influence of MeV electrons irradiation on the gate oxide layers of hydrogenated polysilicon thin film transistors (TFTs) was investigated by measuring gate leakage currents and threshold voltages. The experimental data revealed a decrease of oxide trap density and increase of positive oxide charge. Improvement in the interface roughness and in the oxide quality near the bottom interface was observed.

2006-02-15

116

Influence of MeV electron irradiation on the properties of by ion implantation hydrogenated polysilicon TFTs  

International Nuclear Information System (INIS)

The influence of MeV electrons irradiation on the gate oxide layers of hydrogenated polysilicon thin film transistors (TFTs) was investigated by measuring gate leakage currents and threshold voltages. The experimental data revealed a decrease of oxide trap density and increase of positive oxide charge. Improvement in the interface roughness and in the oxide quality near the bottom interface was observed.

2006-02-01

117

Dosimetric impact of motion in free-breathing and gated lung radiotherapy: A 4D Monte Carlo study of intrafraction and interfraction effects  

UK PubMed Central (United Kingdom)

The purpose of this study was to investigate if interfraction and intrafraction motion in free-breathing and gated lung IMRT can lead to systematic dose differences between 3DCT and 4DCT. Dosimetric...Full Text Available

2008-01-01

118

Correlation between mechanical stress and hydrogen-related effects on radiation-induced damage in MOS structures  

Energy Technology Data Exchange (ETDEWEB)

Correlation between mechanical stress and hydrogen effects on radiation damage in polycide-gate MOS capacitors was investigated as a function of gate-oxide thickness. The compressive stress magnitude was altered by varying the silicide (TiSi/sub 2/ or WSi/sub 2/) thickness in the polycide-gate electrode, and hydrogen introduction into gate-SiO/sub 2/ film was carried out by diffusion from plasma-deposited silicon-nitride passivation film (SiN-Cap). In a MOS capacitor without passivation film (No-Cap sample), it was found that compressive stress on gate-SiO/sub 2/ reduces both positive charge build-up (..delta..Qot) and interface-trap generation (..delta..Dit). Radiation induced shift, ..delta..Qot exhibits a smaller stress effect as compared with ..delta..Dit. As gate-SiO/sub 2/ thickness decreases, the stress effect on ..delta..Qot increases, while this effect ...

1987-12-01

119

Visualization of right atrial appendix by Thallium-201 myocardial scintigraphy: concise communication  

Energy Technology Data Exchange (ETDEWEB)

The atrial myocardium has been barely visible with thallium-201 myocardial scintigraphy. This is probably related to the difference in size, distance from anterior chest wall, and small coronary blood flow of the atrium, compared with the ventricle. We have encountered eight cases of visualization of the right atrial appendix (RAA). The RAA was identified from multiple projections in all cases and sometimes confirmed by radionuclide angiocardiography. Evidence derived from ECG, chest radiographs, and cardiac catheterization, indicated that the most important factor in the visualization might be the displacement of the RAA to a more anterior position.

1980-10-01

120

Hypersersensitivity and Kounis syndrome due to a viper bite  

British Library Electronic Table of Contents (United Kingdom)

A 60-year-old male was bitten by a venomous snake (Vipera ammodytes) and gradually developed signs of an allergic reaction including generalized itching, generalized rash, and chest discomfort. This was followed by severe retrosternal pain with electrocardiographic evidence of an inferior myocardial ischemia progressing to acute myocardial infarction. Cardiac enzymes and troponin, serum tryptase, and histamine were elevated. Coronary arteriography showed normal coronary arteries. This is a characteristic type I variant of Kounis syndrome, which is the concurrence of acute coronary syndromes with conditions associated with mast cell activation including allergic or hypersensitivity reactions as well as anaphylactic or anaphylactoid reactions. This is the first report to show that viper bite...

2006-01-01

121

The effect of oxygen in Ru gate electrode on effective work function of Ru/HfO2 stack structure  

British Library Electronic Table of Contents (United Kingdom)

Effective work function (m,eff) values of Ru gate electrode on SiO2 and HfO2 MOS capacitors were carefully examined and discussed from the viewpoint of an effect of oxygen incorporation in Ru gate electrode on m,eff. Annealing at 400degreeC in the reduction (3%H2) and the oxidation (1%O2) ambient resulted in similar changes in the m,eff of Ru/HfO2/SiO2 and Ru/SiO2 MOS capacitors. Furthermore, the Ru gate MOS capacitor after annealing in the oxidation condition have shown almost the same m,eff value to that of RuO2 gate MOS capacitors. The oxygen concentration in the Ru/HfO2 interface after annealing in oxidizing atmosphere is approximately one order of magnitude higher than that after annealing in reducing atmosphere as confirmed by secondary ion mass spectroscopy analysis. Furthermore, th...

2006-01-01

122

Stable p-channel polysilicon thin film transistors fabricated by laser doping technique  

Energy Technology Data Exchange (ETDEWEB)

In this work we present the electrical characterization of non self-aligned p-channel thin film transistors fabricated by using laser doping technique for source/drain contact formation and gate oxide deposited at room temperature by Electron Cyclotron Resonance Plasma Enhanced Chemical Vapour Deposition. These techniques are suitable for a very low temperature process for TFT fabrication. The output characteristics show a current increase at high drain voltage ('kink' effect) rather moderate, if compared to self aligned polysilicon TFTs, probably due to the gradual doping profile induced by laser doping process. After bias stress at low gate voltage and high drain voltage condition a strong reduction of kink current has been observed in the output characteristics at high drain voltage, whereas minor changes has been observed in the transfer characteristics. This behaviour is similar to what observed in n-channel ...

2005-09-01

123

Stable p-channel polysilicon thin film transistors fabricated by laser doping technique  

International Nuclear Information System (INIS)

In this work we present the electrical characterization of non self-aligned p-channel thin film transistors fabricated by using laser doping technique for source/drain contact formation and gate oxide deposited at room temperature by Electron Cyclotron Resonance Plasma Enhanced Chemical Vapour Deposition. These techniques are suitable for a very low temperature process for TFT fabrication. The output characteristics show a current increase at high drain voltage ('kink' effect) rather moderate, if compared to self aligned polysilicon TFTs, probably due to the gradual doping profile induced by laser doping process. After bias stress at low gate voltage and high drain voltage condition a strong reduction of kink current has been observed in the output characteristics at high drain voltage, whereas minor changes has been observed in the transfer characteristics. This behaviour is similar to what observed in n-channel Gate ...

2005-09-01

124

Simulating quantum search algorithm using vibronic states of I_2 manipulated by optimally designed gate pulses  

International Nuclear Information System (INIS)

In this paper, molecular quantum computation is numerically studied with the quantum search algorithm (Grover's algorithm) by means of optimal control simulation. Qubits are implemented in the vibronic states of I_2, while gate operations are realized by optimally designed laser pulses. The methodological aspects of the simulation are discussed in detail. We show that the algorithm for solving a gate pulse-design problem has the same mathematical form as a state-to-state control problem in the density matrix formalism, which provides monotonically convergent algorithms as an alternative to the Krotov method. The sequential irradiation of separately designed gate pulses leads to the population distribution predicted by Grover's algorithm. The computational accuracy is reduced by the imperfect quality of the pulse design and by the electronic decoherence processes that are modeled by the non-Markovian master equation. ...

2010-04-01

125

Influence of high energy electron irradiation on the characteristics of polysilicon thin film transistors  

Energy Technology Data Exchange (ETDEWEB)

The influence of high energy electron (23 MeV) irradiation on the electrical characteristics of p-channel polysilicon thin film transistors (PSTFTs) was studied. The channel 220 nm thick LPCVD (low pressure chemical vapor deposition) deposited polysilicon layer was phosphorus doped by ion implantation. A 45 nm thick, thermally grown, SiO{sub 2} layer served as gate dielectric. A self-alignment technology for boron doping of the source and drain regions was used. 200 nm thick polysilicon film was deposited as a gate electrode. The obtained p-channel PSTFTs were irradiated with different high energy electron doses. Leakage currents through the gate oxide and transfer characteristics of the transistors were measured. A software model describing the field enhancement and the non-uniform current distribution at textured polysilicon/oxide interface was developed. In order to assess the irradiation-stimulated changes of ...

2006-08-15

126

Influence of high energy electron irradiation on the characteristics of polysilicon thin film transistors  

International Nuclear Information System (INIS)

The influence of high energy electron (23 MeV) irradiation on the electrical characteristics of p-channel polysilicon thin film transistors (PSTFTs) was studied. The channel 220 nm thick LPCVD (low pressure chemical vapor deposition) deposited polysilicon layer was phosphorus doped by ion implantation. A 45 nm thick, thermally grown, SiO_2 layer served as gate dielectric. A self-alignment technology for boron doping of the source and drain regions was used. 200 nm thick polysilicon film was deposited as a gate electrode. The obtained p-channel PSTFTs were irradiated with different high energy electron doses. Leakage currents through the gate oxide and transfer characteristics of the transistors were measured. A software model describing the field enhancement and the non-uniform current distribution at textured polysilicon/oxide interface was developed. In order to assess the irradiation-stimulated changes of ...

2006-08-01

127

Improved detection of myocardial infarction with technetium-99m stannous pyrophosphate and serum MB creatine phosphokinase  

International Nuclear Information System (INIS)

The relative sensitivity and combined value of myocardial technetium-99m stannous pyrophosphate imaging and determinations of serum MB creatine phosphokinase (the ''myocardial'' CPK isoenzyme) in detecting acute myocardial infarction were evaluated in 41 patients with suspected infarction and 23 patients recovering from cardiac surgery. In the patients with suspected infarction, myocardial infarction was confirmed in 25 and was consistently associated with increased serum MB CPK. Abnormal radionuclide images were obtained in 23 of 25 patients (92%)) with definite myocardial infarction and in 2 of 16 patients without confirmed infarction. Although the localization of infarction by imaging correlated well with the localization by electrocardiogram, infarct size estimated by imaging did not correlate well with estimates based on peak total serum CPK activity or serial changes in CPK ...

128

Non cardiopatic and cardiopatic beta thalassaemic patients: quantitative and qualitative cardiac iron deposition evaluation with MRI; Pazienti {beta} talassemici non cardiopatici e cardiopatici: valutazione quantitativa e qualitativa del deposito di ferro cardiaco con RM  

Energy Technology Data Exchange (ETDEWEB)

Purpose: Cardiomyopathy is one of the major complications of {beta} thalassaemia major as a result of transfusion iron overload. The aim of our study is to evaluate with MR if there is any difference of iron deposition signal intensity (SI) or distribution between non-cardiopatic and cardiopatic thalassaemic patients in order to establish if there is a relationship between cardiopathy and iron deposition. Materials and methods: We studied 20 patients affected by {beta} thalassaemia major, of whom 10 cardiopatic and 10 non-cardiopatic, and 10 healthy volunteers as control group. Serum ferritin and left ventricular ejection fraction were calculated in thalassaemic patients. All patients were examinated using a 1.5 MR unit with ECG-gated GE cine-MR T2*-weighted, SE T1-weighted and GE T2*-weighted sequences. In all cases, using an adequate ROI, the myocardial and skeletal muscle signal intensity (SI), the myocardial/skeletal ...

2005-02-01

129

Trigeminocardiac Reflex, Bilateral Sagittal Split Ramus Osteotomy, Gow-Gates Block: A Randomized Controlled Clinical Trial  

British Library Electronic Table of Contents (United Kingdom)

PurposeThe behavior of trigeminocardiac reflex (TCR) during maxillofacial surgeries has not yet been sufficiently studied and knowledge of its behavior is limited to some case reports. The present study aimed to assess the occurrence of TCR in bilateral sagittal split ramus osteotomy and to determine the possible effect of Gow-Gates block on its incidence. Materials and MethodsTwenty candidates for bilateral sagittal split ramus osteotomy (included were American Society of Anesthesiologists I Class III patients with a prognathism of 3 to 5 mm) were given routine general anesthesia after at least 12 hours of fasting. All patients received Gow-Gates mandibular nerve block on 1 random side (case ramus; the other side was used as the control) after induction of general anesthesia before surger...

2011-01-01

130

Mechanical properties of single- and double-gated injection moulded short glass fibre reinforced PBT/PC composites  

British Library Electronic Table of Contents (United Kingdom)

Tensile and flexural properties of single-gated (SG) and double-gated (DG) injection moulded blend of polybutylene terephthalate (PBT) and polycarbonate (PC) and its composites containing 15, 20 and 30?wt.% short glass fibres were investigated. In the DG mouldings, a weldline was formed by direct impingement of two opposing melt fronts (i.e. cold weld). It was found that tensile modulus was not affected by the weldline but flexural modulus decreased in the presence of weldline. For both specimen types, modulus increased linearly with volume fraction of fibres (? f), according to the rule-of-mixtures for moduli. The weldline integrity (WIF) factor for flexural modulus decreased linearly with increasing ? f. Results showed that tensile and flexural strengths for SG mouldings increase with in...

2008-01-01

131

Zinc release from thapsigargin/IP3-sensitive stores in cultured cortical neurons  

UK PubMed Central (United Kingdom)

BackgroundChanges in ionic concentration have a fundamental effect on numerous physiological processes. For example, IP3-gated thapsigargin sensitive intracellular calcium...Full Text Available

132

Tarantula Huwentoxin-IV Inhibits Neuronal Sodium Channels by Binding to Receptor Site 4 and Trapping the Domain II Voltage Sensor in the Closed Configuration*S?  

UK PubMed Central (United Kingdom)

Peptide toxins with high affinity, divergent pharmacological functions, and isoform-specific selectivity are powerful tools for investigating the structure-function relationships of voltage-gated...Full Text Available

2008-10-03

133

PubTeX output 2001.06.04:1654  

Science.gov (United States)

estate in terms of runways, taxiways, and terminal ramp areas. .... queueing time into gate delays. It is therefore reasonable to conclude that minimization of ...... tities chosen are to illustrate the stochastic effect of noncom- ...

134

Novel Analogs and Stereoisomers of the Marine Toxin Neodysiherbaine with Specificity for Kainate Receptors  

UK PubMed Central (United Kingdom)

Antagonists for kainate receptors (KARs), a family of glutamate-gated ion channels, are efficacious in a number of animal models of neuropathologies, including epilepsy, migraine pain, and anxiety....Full Text Available

2008-02-01

135

Investigations on the quality of polysilicon film-gate dielectric interface in polysilicon thin film transistors  

Energy Technology Data Exchange (ETDEWEB)

The effective electron mobility was measured as a function of surface field in polysilicon thin film transistors having the following three types of gate dielectrics; silicon dioxide deposited by low temperature (350degC) plasma-enhanced chemical vapor deposition (PECVD), low temperature (400degC) nitrogen-rich PECVD silicon nitride and high temperature (1050degC) thermally grown silicon dioxide. At low surface fields, the maximum true effective electron mobility was 40[+-]3 cm[sup 2] V[sup -1] s[sup -1] in all devices independent of the type of gate dielectric, indicating that the quality of the interface is the same. However, at high surface fields a stronger degradation of the mobility was observed in devices having the thermally grown silicon dioxide as gate dielectric, indicating the presence of surface roughness within the interfacial region. The polysilicon structure was studied by transmission electron microscopy in ...

1992-08-28

136

Gate-oxide integrity for polysilicon thin-film transistors: a comparative study for ELC, MILC and SPC crystallized active polysilicon layer  

International Nuclear Information System (INIS)

In this paper, we present the results of Plasma-Enhanced Chemical Vapor Deposition gate-oxide (SiO_2) integrity on ELC (excimer-laser-crystallized), MILC (metal-induced lateral-crystallized) and SPC (solid-phase-crystallized) polysilicon films. We observed that gate oxide strength of poly-Si TFT strongly depends on the crystallization method for the active silicon layer. In the case of ELC films, asperities on the silicon surface reduce the SiO_2 breakdown field significantly. The metallic contaminants in MILC films are responsible for a deleterious impact on gate oxide integrity. Among the three cases, the SiO_2 breakdown field was the highest for the SPC silicon films. The breakdown fields at the 50 % failure points in Weibull plots for the ELC, MILC and SPC cases were 5.1 MV/cm, 6.2 MV/cm, and 8.1 MV/cm, respectively. We conclude that the roughness and metallic contamination of the poly-Si films are the main factors that ...

2006-01-01

137

GaAs REI,IABILITY DATARASE '-r. SACCO, S . C+ ON Z, AItIli ...  

Science.gov (United States)

Direct coupljng between Al and Au metal]jzations can result in an increase in gate resistance due to a metallurgical reaction. (purple plague). An RF life test on ...

138

Central gating of fly optomotor response  

UK PubMed Central (United Kingdom)

We study the integration of multisensory and central input at the level of an identified fly motoneuron, the ventral cervical nerve motoneuron (VCNM) cell, which controls head movements of the animal....Full Text Available

2010-11-16

139

Apparatus for opening and closing the gate of a coal tower  

Energy Technology Data Exchange (ETDEWEB)

A pneumatic device is in the form of a U-shaped frame, on which a prong is attached by using two pairs of levers. It also has a hydraulic or pneumatic cyclinder, whose rod is connected to one of the pairs of levers. All connections are hinges.

1981-08-23

140

A novel rat strain with enhanced sensitivity to the effects of dopamine agonists on startle gating  

UK PubMed Central (United Kingdom)

BackgroundCompared to outbred Sprague Dawley (SD) rats, inbred Brown Norway (BN) rats exhibit less prepulse inhibition of startle (PPI) at long prepulse intervals,...Full Text Available

2008-01-01

141

SEU hardening of field programmable gate arrays (EPGAS) for space applications and device characterization  

International Nuclear Information System (INIS)

Field Programmable Gate Arrays (FPGAs) are being used in space applications because of attractive attributes: good density, moderate speed, low cost, and quick turn-around time. However, these devices are susceptible to Single Event Upsets (SEUs). An approach using triple modular redundancy (TMR) and feedback was developed for flip-flop hardening in these devices. Test data showed excellent results for this circuit topology. Total dose and Single Event Effect (SEE) testing have been performed on recently released technologies. Failures are analyzed and test methodology is discussed.

1994-07-18

142

Radiation hardening characterization of a VDMOS developed at CAS institute of microelectronics  

International Nuclear Information System (INIS)

Total dose irradiation effects on a VDMOS developed at Institute of Microelectronics, CAS were investigated, particularly the electric parameter changes under different bias conditions. It was found that the breakdown voltage degradation by the irradiation depended mainly on the drain bias, whereas the threshold voltage degradation depended mainly on the gate bias. Thus, an innovative and effective method to domestic VDMOS total dose ionization characterization is that threshold voltage radiation hardening characterization should be tested on gate bias condition, and the breakdown voltage radiation hardening characterization, be tested on the drain bias. (authors)

2008-08-01

143

Quantum Computation with Nonlinear Optics  

International Nuclear Information System (INIS)

We propose a scheme of quantum computation with nonlinear quantum optics. Polarization states of photons are used for qubits. Photons with different frequencies represent different qubits. Single qubit rotation operation is implemented through optical elements like the Faraday polarization rotator. Photons are separated into different optical paths, or merged into a single optical path using dichromatic mirrors. The controlled-NOT gate between two qubits is implemented by the proper combination of parametric up and down conversions. This scheme has the following features: (1) No auxiliary qubits are required in the controlled-NOT gate operation; (2) No measurement is required in the course of the computation; (3) It is resource efficient and conceptually simple.

2008-01-15

144

Phonon-mediated entanglement for trapped ion quantum computing  

Energy Technology Data Exchange (ETDEWEB)

Trapped ions are a near ideal system to study quantum information processing due to the high degree of control over the ion's external confinement and internal degrees of freedom. We demonstrate the key steps necessary for trapped ion quantum computing and focus on phonon-mediated entangling gates. We highlight several key algorithms implemented over the last decade with these gates and give a detailed description of Grover's quantum database search implemented with two trapped ion qubits.

2010-03-15

145

Chemical sensitivity of Mo gate Mos capacitors  

International Nuclear Information System (INIS)

Mo gate Mos capacitors exhibit a negative shift of their C-V characteristic by up to 240 mV, at 125 C, in response to 1000 ppm hydrogen, in controlled nitrogen atmospheres. The experimental methods for obtaining capacitance and conductance, as a function of polarisation voltage, as well as the relevant equivalent circuits are reviewed. The single-state interface state density, at the semiconductor-dielectric interface, decreases from 2.66 x 10"1"1 cm"-"2 e-v"-"1, in pure nitrogen, to 2.5 x 10"1"1 cm"-"2 e-v"-"1 in 1000 ppm hydrogen in nitrogen mixtures, at this temperature. (Author)

146

Trace Elements in Human Myocardial Infarction Determined by Neutron Activation Analysis  

International Nuclear Information System (INIS)

By means of neutron activation analysis, injured and adjacent uninjured human heart tissue from 12 autopsy cases with myocardial infarction are investigated with respect to the concentration of 23 trace elements. The bulk elements K, Na and P are also determined. A recently developed ion-exchange technique, combined with subsequent y-spectrometry, is used. The following trace elements are determined: Ag, As, Au, Ba, Br, Ca, Cd, Ce, Co, Cr, Cs, Cu, Fe, Hg, La, Mo, Rb, Sb, Sc, Se, Sm, Zn and W. In the injured tissue compared to the uninjured, calculation on a wet weight basis showed a decrease in Co, Cs, K, Mo, P, Rb and Zn, and an increase in Br, Ca, Ce, La, Na, Sb and Sm. The differences in Ca, La, Mo, P and Zn are dependent on the age of the myocardial infarction, and the regression lines for these elements are given. The concentration of the trace elements in uninjured tissue from infarcted hearts is compared to the concentration of these ...

1965-01-01

147

Regional myocardial perfusion in patients with atherosclerotic coronary artery disease, at rest and during angina pectoris induced by tachycardia  

International Nuclear Information System (INIS)

We studied regional myocardial perfusion by scintigraphic computer-assisted analysis of initial distribution, washout rates, and residual activity of "1"3"3Xe injected into the left coronary artery of four patients with normal arteriograms and 14 patients with coronary stenosis. At rest, residual activity in poststenotic regions was always greater than in control regions, but initial washout rates were not slower. During angina, following xenon injections, the amount of indicator distributed to the poststenotic regions was markedly reduced; the increase of the initial washout rates was smaller than in control regions relative to rest, and residual activity was higher. Initial washout rates did not differ as much as from those of normal myocardium because in severe ischemia too little indicator is deposited initially in these regions to produce a change of any magnitude. Indeed, when angina was induced immediately after the xenon injection, poststenotic washout ...

148

Transplantation of progenitor cells and regeneration enhancement in acute myocardial infarction (TOPCARE-AMI): final 5-year results suggest long-term safety and efficacy  

British Library Electronic Table of Contents (United Kingdom)

Background Limited data is available for investigating the long-term safety and effects of intracoronary progenitor cell therapy in patients with acute myocardial infarction (AMI). Objective To assess the clinical course, NT-proBNP and MRI data as objective markers of cardiac function of the TOPCARE-AMI patients at 5-year follow-up. Design The TOPCARE-AMI trial was the first randomized study investigating the effects of intracoronary infusion of circulating (CPC) or bone marrow-derived progenitor cells (BMC) in 59 patients with successfully reperfused AMI. Results Five-year follow-up data were completed in 55 patients, 3 patients were lost to follow-up. None of the patients showed any signs of intramyocardial calcification or tumors at 5?years. One patient died during the initial hospitali...

2011-01-01

149

Association Between Wasted Pressure Effort and Left Ventricular Hypertrophy in Hypertension: Influence of Arterial Wave Reflection  

British Library Electronic Table of Contents (United Kingdom)

BackgroundWave reflection during the systole increases left ventricular (LV) pressure, tension-time index (TTI) and myocardial oxygen requirement. The purpose of this study was to extract that component of extra myocardial oxygen requirement that is due to early systolic wave reflection, define it as wasted effort (?Ew), and examine its relationship to LV hypertrophy (LVH).MethodsRadial artery pressure waveforms were recorded using applanation tonometry and central aortic waveforms generated in 98 patients with untreated hypertension. Aortic augmentation index (AIa), wave reflection amplitude (i.e., aortic augmented pressure (AG)) and systolic duration (ED?Tr), ejection duration (ED) and round-trip travel time of the pressure wave (Tr) were calculated from the aortic waveform, a...

2008-01-01

150

[Heart injuries: diagnosis and therapy].  

Science.gov (United States)

The clinical manifestation of wounds of the heart is determined by the mode, site and size of the injury as well as the structure of the pericardial and myocardial lesion. Diagnosis can be confirmed by ECG and echocardiography. Only 20% of the patients with penetrating wounds of the heart live for more than 30 minutes. Pericardio-centesis should be used only to gain time for a safe sternotomy, cardiac decompression and suture of the wound of the heart. An aggressive surgical approach is mandatory. Cardiopulmonary bypass is necessary only to correct of concomitant lesions. PMID:1983618

1990-01-01

151

Should coronary angiography be the gold standard? A study correlating thallium myocardial scintigraphy, translesional pressure gradient and percent stenosis  

International Nuclear Information System (INIS)

Coronary angiography provides anatomical information whereas thellium myocardial scintigraphy measures resistive tissue perfusion. Because of this fundamental difference. The authors question the validity of using coronary angiography as the gold standard to judge thellium myocardial scintigraphy. The authors studied 20 patients undergoing elective percutaneous coronary angioplasty who fulfilled the following criteria: (1) history of chest pain; (2) angiographically significant single vessel disease (>50% stenosis); (3) no prior myocardial infarction. All patients underwent maximal exercise thallium single photon emission computed tomography (T1-SPECT). Tl-SPECT was scored visually according to a 0 to 3 scale (0=absent uptake; 1=markedly decreased uptake; 2=minimally decreased uptake; 3=normal uptake). Translesional gradient and percent stenosis were measured before and after angioplasty. The authors found that ...

1985-06-02

152

Relation Between Myocardial Infarction Deaths and Solar Activity in Mexico  

Science.gov (United States)

We study the daily incidence of myocardial infarction deaths in Mexico for 4 years (1996-99) with a total of 129 917 cases in all the country, collected at the General Directorate of Epidemiology (National Ministry of Health). We divided the cases by sex and age and perform two kinds of analysis. First, we did an spectral analysis using the Maximum Entropy Method, considering the complete period, and minimum and maximum epochs of solar activity. The results show that the most persistent periodicity at higher frequencies in the myocardial infarction death occurrence is that of seven days. Considering the solar cycle phases, we found that during solar minimum times some frequencies are not detectable compared with solar maximum epochs, particularly that of seven days. Biological rhythms close to seven days, the circaseptans, are in general thought to be only the result of the social organization of life. However, this cannot be the only ...

2002-05-01

153

Myeloid-Related Protein-8/14 and the Risk of Cardiovascular Death or Myocardial Infarction after an Acute Coronary Syndrome in the PROVE IT-TIMI 22 Trial  

UK PubMed Central (United Kingdom)

BackgroundUsing a transcriptional profiling approach, we recently identified myeloid-related protein-8/14 (MRP-8/14) to be expressed by platelets during acute MI....Full Text Available

2008-01-01

154

MRI in the diagnosis of non-compacted ventricular Myocardium (NCVM) compared to echocardiography  

International Nuclear Information System (INIS)

Purpose: To report the detection of con-compacted ventricular myocardium (NVCM) with MRI compared to echocardiography in 8 patients. Material and methods: Non-compaction of the ventricular myocardium is a congenital disorder characterized by an altered structure of the myocardial wall resulting from an intrauterine arrest in endomyocardial embryogenesis. The morphological findings consist of a prominent meshwork of multiple myocardial trabeculations and deep intertrabecular recesses, communicating with the left ventricular cavity. 8 consecutive patients (mean age 7.3 years) with clinical and echocardiographic signs of NCVM were examined by MRI (1.5 T, Vision, Siemens) in short axis and 2- and 4-chamber views, using T_1-weighted TSE and Cine-GRE in 6 patients and true FISP sequences in 2 patients. MRI and echocardiography were evaluated for visibility, signs of NCVM and involvement of myocardial wall segments. Thickness was ...

2003-09-01

155

Lyme myocarditis diagnosed by indium-111-antimyosin antibody scintigraphy  

Energy Technology Data Exchange (ETDEWEB)

We report a new case of Lyme disease with cardiac manifestations, which has been possible to follow during the long period of 12 years. We have detected the usual ECG abnormalities, and concentric hypertrophic myocardiopathy, by echocardiography. The acute myocarditis was demonstrated by /sup 111/In-antimyosin scintigraphy, which showed global myocardial uptake of the tracer, constituting the first report, to our knowledge, of Lyme myocarditis diagnosed by this method.

1989-06-01

156

Kappa-opioid receptor activation during reperfusion limits myocardial infarction via ERK1/2 activation in isolated rat hearts  

UK PubMed Central (United Kingdom)

BackgroundWe investigated whether p42/p44 extracellular signal-regulated kinases (ERK1/2) and/or phosphatidylinositol-3-OH kinase (PI3K)-Akt play a crucial role in cardioprotection...Full Text Available

2011-05-01

157

Comparison of enhanced device response and predicted x-ray dose enhancement effects on MOS oxides  

Energy Technology Data Exchange (ETDEWEB)

The response of MOS capacitors to low- and medium-energy x-ray irradiation is investigated as a function of gate material (TaSi or Al), oxide thickness, and electric field. Measured device response is compared with predictions based on discrete ordinates and Monte Carlo code simulations of dose enhancement effects, coupled with recent estimates of electron-hole recombination in MOS oxides. In comparisons of 10-keV x-ray and Co-60 irradiations of Al-gate MOS capacitors at an oxide electric field of 1 MV/cm, it is found that predictions and experiments agree to within better than 20 percent for oxide thicknesses ranging from 35 to 1060 nm. For capacitors having TaSi/Al gates, predictions and experiments agree to within better than 30 percent at 1 MV/cm, with the largest differences occurring for 35-nm gate oxides. At other electric fields, the disagreement between experiment and prediction increases ...

1988-12-01

158

Comparison of enhanced device response and predicted x-ray dose enhancement effects on MOS oxides  

International Nuclear Information System (INIS)

The response of MOS capacitors to low- and medium-energy x-ray irradiation is investigated as a function of gate material (TaSi or Al), oxide thickness, and electric field. Measured device response is compared with predictions based on discrete ordinates and Monte Carlo code simulations of dose enhancement effects, coupled with recent estimates of electron-hole recombination in MOS oxides. In comparisons of 10-keV x-ray and Co-60 irradiations of Al-gate MOS capacitors at an oxide electric field of 1 MV/cm, it is found that predictions and experiments agree to within better than 20 percent for oxide thicknesses ranging from 35 to 1060 nm. For capacitors having TaSi/Al gates, predictions and experiments agree to within better than 30 percent at 1 MV/cm, with the largest differences occurring for 35-nm gate oxides. At other electric fields, the disagreement between experiment and prediction increases ...

1988-07-12

159

Radiation effects on MOS devices and radiation-hard CMOS technologies  

International Nuclear Information System (INIS)

Total-dose irradiation seriously damages MOS devices and their circuit performance. Threshold voltage shifts, transconductance degradation and increase in off-state leakage current are generally observed for irradiated devices. These instabilities are essentially due to positive and/or negative charge trapping in SiO_2 and interface trap generation at the SiO_2/Si interface. Radiation hardening of CMOS VLSIs is to eliminate these trapping effects, and for this purpose, special considerations for fabrication processes and layout design are necessary. In this paper, basic mechanisms for radiation-induced charge trapping and related effects on MOS devices are reviewed. Also discussed are radiation-hardening technologies from both fabrication-process and layout-design viewpoints. Using these technologies, 1 #mu#m radiation-hard CMOS gate arrays have been successfully developed. Experimental data taken for 2k-gate test chips indicate that radiation ...

160

Electric characteristics of organic thin-film transistors and logic circuits with a ferroelectric gate insulator  

Energy Technology Data Exchange (ETDEWEB)

Organic electronic devices using a pentacene have improved importantly in the last several years. We fabricated pentacene organic thin-film transistors (OTFTs) with dielectric SiO{sub 2} and ferroelectric Pb(Zr{sub 0.3},Ti{sub 0.7})O{sub 3} (PZT) gate insulators. The organic devices using SiO{sub 2} and PZT films had the field-effect mobility of approximately 0.1 and 0.004 cm{sup 2}/V s, respectively. The drain current in the transfer curve of pentacene/PZT transistors showed a hysteresis behavior originated in a ferroelectric polarization switching. In order to investigate the polarization effect of PZT gate dielectrics in a logic circuit, the simple voltage inverter using SiO{sub 2} and PZT films was fabricated and measured by an output-input measurement. The gain of inverter at the poling-down state was approximately 7.2 and it was three times larger than the value measured at the poling-up state.

2007-07-16

161

Time-resolved electron-beam characterizations with optical transition radiation  

Energy Technology Data Exchange (ETDEWEB)

Time-resolved characterizations of electron beams using optical transition radiation (OTR) as a prompt conversion mechanism have recently been extended on the Los Alamos Free-electron Laser (FEL) facility 40-MeV linac. Two key timescales for rf-linac driven FELs are the micropulse (10 ps) and the macropulse (5 {mu}s to 1 ms). In the past we have used gated, intensified cameras to select a single or few micropulses (25 to 400 ns gate width) out of the pulse train to evaluate submacropulse effects. Recently, we have obtained some of the first measurements of micropulse bunch length (7 to 10 ps) and submacropulse spatial position and profile using OTR and a Hamamatsu streak camera. Additionally, micropulse elongation effects and head-to-tail transverse kicks are reported as a function of charge.

1992-01-01

162

Time-resolved electron-beam characterizations with optical transition radiation  

Energy Technology Data Exchange (ETDEWEB)

Time-resolved characterizations of electron beams using optical transition radiation (OTR) as a prompt conversion mechanism have recently been extended on the Los Alamos Free-electron Laser (FEL) facility 40-MeV linac. Two key timescales for rf-linac driven FELs are the micropulse (10 ps) and the macropulse (5 {mu}s to 1 ms). In the past we have used gated, intensified cameras to select a single or few micropulses (25 to 400 ns gate width) out of the pulse train to evaluate submacropulse effects. Recently, we have obtained some of the first measurements of micropulse bunch length (7 to 10 ps) and submacropulse spatial position and profile using OTR and a Hamamatsu streak camera. Additionally, micropulse elongation effects and head-to-tail transverse kicks are reported as a function of charge.

1992-09-01

163

The Bipolar Field-Effect Transistor: VIII. Longitudinal Gradient of Longitudinal Electric Field (Two-MOS-Gates on Pure-Base)  

International Nuclear Information System (INIS)

This paper evaluates the electric current terms from the longitudinal gradient of the longitudinal electric field in Bipolar Field-Effect-Transistors (BiFETs) with a pure base and two MOS gates operating in the unipolar (electron) current mode. These nMOS-BiFETs, known as nMOS-FinFETs, usually have electrically short channels compared with their intrinsic Debye length of about 25 #mu#m at room temperatures. These longitudinal electric current terms are important short-channel current components, which have been neglected in the computation of the long-channel electrical characteristics. This paper shows that the long-channel electrical characteristics are substantially modified by the longitudinal electrical current terms when the physical channel length is less than 100 nm.

2010-07-01

164

Silicon oxide conductivity of hydrogen ion implanted polysilicon thin film transistors  

Energy Technology Data Exchange (ETDEWEB)

The influence of hydrogen ion implantation into the channel polysilicon of polysilicon thin film transistors on gate oxide conductivity has been investigated. Data for effective tunnelling barriers at the gate oxide/channel polysilicon interface are presented. A value of 1.2eV for samples with boron doped channel polysilicon is calculated. For hydrogenated boron doped samples tunnelling barriers higher than 2.1 eV are obtained. The tunnelling barriers for phosphorus doped samples are impurity concentration dependent and decrease with increasing phosphorus concentration in the range 3 x 10{sup 17} to 3 x 10{sup 19} cm{sup -3}. (Author).

1996-10-01

165

Silicon oxide conductivity of hydrogen ion implanted polysilicon thin film transistors  

International Nuclear Information System (INIS)

The influence of hydrogen ion implantation into the channel polysilicon of polysilicon thin film transistors on gate oxide conductivity has been investigated. Data for effective tunnelling barriers at the gate oxide/channel polysilicon interface are presented. A value of 1.2eV for samples with boron doped channel polysilicon is calculated. For hydrogenated boron doped samples tunnelling barriers higher than 2.1 eV are obtained. The tunnelling barriers for phosphorus doped samples are impurity concentration dependent and decrease with increasing phosphorus concentration in the range 3 x 10"1"7 to 3 x 10"1"9 cm"-"3. (Author).

166

Light weight underground pipe or cable installing device  

Energy Technology Data Exchange (ETDEWEB)

This invention pertains to a light weight underground pipe or cable installing device adapted for use in a narrow and deep operating trench. More particularly this underground pipe installing device employs a pair of laterally movable gates positioned adjacent the bottom of the operating trench where the earth is more solid to securely clamp the device in the operating trench to enable it to withstand the forces exerted as the actuating rod is forced through the earth from the so-called operating trench to the target trench. To accommodate the laterally movable gates positioned adjacent the bottom of the narrow pipe installing device, a pair of top operated double-acting rod clamping jaws, operated by a hydraulic cylinder positioned above the actuating rod are employed.

1985-01-08

167

Ge/Si nanowire mesoscopic Josephson junctions  

CERN Document Server

The controlled growth of nanowires (NWs) with dimensions comparable to the Fermi wavelengths of the charge carriers allows fundamental investigations of quantum confinement phenomena. Here, we present studies of proximity-induced superconductivity in undoped Ge/Si core/shell NW heterostructures contacted by superconducting leads. By using a top gate electrode to modulate the carrier density in the NW, the critical supercurrent can be tuned from zero to greater than 100 nA. Furthermore, discrete sub-bands form in the NW due to confinement in the radial direction, which results in stepwise increases in the critical current as a function of gate voltage. Transport measurements on these superconductor-NW-superconductor devices reveal high-order (n = 25) resonant multiple Andreev reflections, indicating that the NW channel is smooth and the charge transport is highly coherent. The ability to create and control coherent superconducting ordered states ...

2006-01-01

168

Further time-resolved electron-beam characterizations with optical transition radiation  

Energy Technology Data Exchange (ETDEWEB)

Time-resolved characterizations of electron beams using optical transition radiation (OTR) as a prompt conversion mechanism have recently been extended on the Los Alamos Free-electron Laser (FEL) facility 40-MeV linac. Two key timescales for rf-linac driven FELs are the micropulse (10 ps) and the macropulse (5 [mu]s to 1 ms). In the past we have used gated, intensified cameras to select a single or few micropulses (25 to 400 ns gate width) out of the pulse train to evaluate submacropulse effects. Recently, we have obtained some of the first measurements of micropulse bunch length (7 to 10 ps) and submacropulse spatialposition and profile using OTR and a Hamamatsu streak camera. Additionally, micropulse elongation effects and head-to-tail transverse kick effects are reported as a function of charge.

1992-01-01

169

Further time-resolved electron-beam characterizations with optical transition radiation  

Energy Technology Data Exchange (ETDEWEB)

Time-resolved characterizations of electron beams using optical transition radiation (OTR) as a prompt conversion mechanism have recently been extended on the Los Alamos Free-electron Laser (FEL) facility 40-MeV linac. Two key timescales for rf-linac driven FELs are the micropulse (10 ps) and the macropulse (5 {mu}s to 1 ms). In the past we have used gated, intensified cameras to select a single or few micropulses (25 to 400 ns gate width) out of the pulse train to evaluate submacropulse effects. Recently, we have obtained some of the first measurements of micropulse bunch length (7 to 10 ps) and submacropulse spatialposition and profile using OTR and a Hamamatsu streak camera. Additionally, micropulse elongation effects and head-to-tail transverse kick effects are reported as a function of charge.

1992-12-31

170

5 GHz GaAs monolithic astable multivibrator type voltage controlled oscillator  

Science.gov (United States)

A 5 GHz GaAs monolithic astable multivibrator-type voltage-controlled oscillator has been developed. The monolithic oscillator uses 2 micron long self-aligned TiW-silicide gate MESFETs as well as GaAs Schottky diodes for capacitance. Good agreement between the experiment and calculations for oscillation frequency characteristics versus control voltage is obtained by assuming donor density in the FET active layer to be a Gaussian distribution. This oscillator is useful for monolithic front ends and phase-locked oscillators used in microwave signal processing. X-band oscillation frequency can be obtained with 1 micron long gate FET and low loss resonance inductors.

1984-03-01

171

Effects of carbon monoxide on myocardial ischemia  

Energy Technology Data Exchange (ETDEWEB)

The purpose of this study was to determine whether low doses of carbon monoxide (CO) exacerbate myocardial ischemia during a progressive exercise test. The effect of CO exposure was evaluated using the objective measure of time to development of electrocardiographic changes indicative of ischemia and the subjective measure of time to onset of angina. Sixty-three male subjects (41-75 years) with well-documented coronary artery disease, who had exertional angina pectoris and ischemic ST-segment changes in their electrocardiograms, were studied. Results from three randomized, double-blind test visits (room air, low and high CO) were compared. The effect of CO exposure was determined from the percent difference in the end points obtained on exercise tests performed before and after a 1-hr exposure to room air or CO. A significant dose-response relationship was found for the individual differences in the time to ST end point and angina for the pre-versus postexposure ...

1991-02-01

172

Determination of left ventricular ejection fraction and wall thickness in magnetic resonance imaging at 1.0 Tesla in comparison to echocardiography and biplanar ventriculography  

International Nuclear Information System (INIS)

We compared the values of the myocardial thickness and the left ventricle diameters measured with MRI and echocardiography. The ejection fraction was compared in MRI and ventriculography. 34 patients with different heart dysfunctions were examined with MRI (FISP 2D sequence). 26 of them were also studied by echocardiography and 20 by biplane cine-ventriculography. The enddiastolic thicknesses of the left ventricular postero-lateral wall and of the septum interventriculare were measured on short axis images. An ellipsoidal modell was used for volume calculation and ejection fraction. Correlation of MRI values of thickness and ejection fraction with echocardiographi and angiographi showed r>0,8. As known for 1.56 T Imagers, the myocardial thickness in MRI was underestimated compared to echocardiography (1.4 mm#+-#1.7). The ejection fraction was underevaluated compared to ventriculography (4.5%#+-#10.1). MRI (1.0 T) accurately measures ...

173

Changes in myocardial beta1-adrenergic receptor and stimulatory G-protein gene expression after chronic treatment with doxorubicin in rat.  

Science.gov (United States)

The gene expression of beta(1)-adrenergic receptor (beta(1)AR) and stimulatory G-protein Gsalpha in ventricle after chronic treatment with doxorubicin (DOX) in rat was investigated. The rats were treated with DOX in a dose of 2.5 mg/kg once a week for 5 weeks, the cumulative dose being 12.5 mg/kg. Two weeks after the last injection, the positive inotropic effect of isoproterenol was noticeably decreased in left atrial muscle preparations isolated from DOX-treated rats. Northern blot hybridization showed that the mRNA transcripts of beta(1)AR and Gsalpha, important signal transduction elements for regulating heart rate and contractility, were significantly decreased in the ventricle of DOX-treated rats. Thus, chronic treatment with DOX decreases the gene expression levels of myocardial beta(1)AR and Gsalpha. PMID:15353854

2004-08-01

174

Assessment of PET and MRI Polar Map using Gaussian Mixture Model  

International Nuclear Information System (INIS)

Cardiac disease research relies increasingly on small animal models and non-invasive imaging methods such as positron emission tomography (PET) and magnetic resonance imaging (MRI). Delayed enhancement magnetic resonance imaging (DE-MRI) using gadolinium-based contrast agents appear to be a visualizing infracted myocardium with high spatial resolution. Polar map (or bull's-eye image) was used to determination of the myocardial infarction area. Polar map is a comprehensive interpretation of the left ventricle. The infarct size was computed as the fraction of the total polar map areas. The threshold was computed as the percentage of mean intensity of the normal region. In other study, 50% predefined threshold value in varying range (30?70%) was most commonly use. However, predefined threshold value isn't acceptance in all case. The purpose of this study was to investigate methodological approach for automatic measurement of rat myocardial infarct ...

2010-10-01

175

Adenosine triphosphate loading thallium-201 myocardial scintigraphy. Optimal dose and diagnostic accuracy  

Energy Technology Data Exchange (ETDEWEB)

Adenosine triphosphate (ATP) is an alternative to dipyridamole or adenosine in thallium-201 myocardial scintigraphy. However, the optimal dose of ATP has not been determined. A Doppler guide wire study showed the coronary flow velocity at a dose of 0.15 mg/kg of ATP was equal or higher than that at 0.14 mg/kg of adenosine or 0.56 mg/kg of dipyridamole. ATP was given intravenously to 67 patients with coronary artery disease at 0.15 mg/kg/min for 6 min. Thallium-201 was injected at 3 min, followed by immediate and delayed (3 hrs) tomographic imaging. There was no serious side effect during examination, although chest pain (26%), dyspnea (17%), and flushing (33%) were common. The sensitivity and specificity to detect coronary artery disease were 98 and 100%, respectively. The sensitivity to detect left anterior descending artery, left circumflex artery, and right coronary artery lesions was 94, 59 and 77%, respectively. ATP loading thallium-201 scintigraphy provides ...

1995-01-01

176

Unique Bell-shaped Voltage-dependent Modulation of Na+ Channel Gating by Novel Insect-selective Toxins from the Spider Agelena orientalis*  

UK PubMed Central (United Kingdom)

Spider venoms provide a highly valuable source of peptide toxins that act on a wide diversity of membrane-bound receptors and ion channels. In this work, we report isolation, biochemical analysis, and...Full Text Available

2010-06-11

177

Total dose hardening of SIMOX buried oxides for fully depleted devices in rad-tolerant applications  

International Nuclear Information System (INIS)

A total dose hardening treatment is applied to SIMOX buried oxides. Total ionizing dose radiation testing is performed on fully-depleted transistors fabricated on both hardened and non-hardened substrates. At 200 krads x-ray dose, the front gate shift is reduced from -0.7 to -0.2 V for FETs built on the hardened wafers.

1996-07-15

178

Search for anisotropy in the L x-gamma angular correlations following the decay of "2"0"7Bi  

International Nuclear Information System (INIS)

An investigation of the Ll x-#gamma# angular correlations following the decay of "2"0"7Bi is done by using a Si(Li) semiconductor counter as L x-ray detector. Coincidence measurements at five different angles were made between the 570-keV #gamma# ray (gated in the movable counter) and the Ll x spectrum (displayed in a multichannel analyzer).

179

Regional evaluation of the coal-bed methane potential of the foothills/mountains of Alberta  

Energy Technology Data Exchange (ETDEWEB)

The coal bed methane (CBM) potential of five coal zones (the Kootenay, Gething, Gates, Brazeau, and Coalspur) in the Alberta foothills and mountains is re-evaluated. For evaluation, the coal zones are divided into shallow (200 to 2500 m depth) and deep (over 2500 m depth). The total gas content is estimated. Recommendations on how to obtain more reliable resource data and about producibility are included. 41 refs., 12 figs., 3 tabs., 2 apps.

2001-09-01

180

Quantum computing with trapped ions  

Energy Technology Data Exchange (ETDEWEB)

Quantum computers hold the promise of solving certain computational tasks much more efficiently than classical computers. We review recent experimental advances towards a quantum computer with trapped ions. In particular, various implementations of qubits, quantum gates and some key experiments are discussed. Furthermore, we review some implementations of quantum algorithms such as a deterministic teleportation of quantum information and an error correction scheme.

2008-12-15

181

Quantum Discrete Fourier Transform in an Ion Trap System  

International Nuclear Information System (INIS)

We propose two schemes for the implementation of quantum discrete Fourier transform in the ion trap system. In each scheme we design a tunable two-qubit phase gate as the main ingredient. The experimental implementation of the schemes would be an important step toward complex quantum computation in the ion trap system.

2007-06-15

182

Pore properties and pharmacological features of the P2X receptor channel in airway ciliated cells  

UK PubMed Central (United Kingdom)

Airway ciliated cells express an ATP-gated P2X receptor channel of unknown subunit composition (P2Xcilia) which is modulated by Na+ and by long exposures to ATP. P2Xcilia...Full Text Available

2006-03-15

183

Point/counterpoint: dose-related issues in cardiac CT imaging  

British Library Electronic Table of Contents (United Kingdom)

This manuscript reviews some of the more controversial dose-related issues in cardiac CT imaging. Discussion covers the relative merits of cardiac CT versus MR, advantages and concerns regarding gated versus nongated cardiac CT and advantages and concerns regarding the use of breast shields in girls undergoing cardiac CT imaging.

2011-01-01

184

Mutations at the accommodation gate of the ribosome impair RF2-dependent translation termination  

UK PubMed Central (United Kingdom)

During protein synthesis, aminoacyl-tRNA (aa-tRNA) and release factors 1 and 2 (RF1 and RF2) have to bind at the catalytic center of the ribosome on the 50S subunit where they take part in peptide bond...Full Text Available

2010-09-01

185

Hal; a block level hardware logic simulator  

Energy Technology Data Exchange (ETDEWEB)

A special purpose hardware machine, which simulates up to one half-million gates and 2m byte RAM ICS at a 5 millisecond clock speed is described. This is accomplished with a hardware logic (HAL) simulator. This performance is achieved with 32 distributed special parallel processors, which utilize block oriented simulation technique. The technique promises a good cost hardware logic simulator. 7 references.

1983-01-01

186

Extended range chemical sensing apparatus  

Energy Technology Data Exchange (ETDEWEB)

An apparatus for sensing chemicals over extended range of concentrations. In particular, first and second sensors each having separate, but overlapping ranges for sensing concentrations of hydrogen are provided. Preferably, the first sensor is a MOS solid state device wherein the metal electrode or gate is a nickel alloy. The second sensor is a chemiresistor comprising a nickel alloy.

1994-01-01

187

Development on astable multivibrators using the combination of linear and non-linear materials as switching elements based on all optial method  

Science.gov (United States)

In this communication we propose a method to implement an all-optical astable multivibrator using the non-linear material based switches and logic gates. The scheme can operate in real time. The delay time can achieve ps(pico-second). The pulse duration can be made very low and may cross the THz easily by selecting proper material and laser source.

2009-03-01

188

Computed tomography - old ideas and new technology  

International Nuclear Information System (INIS)

Several recently introduced 'new' techniques in computed tomography - iterative reconstruction, gated cardiac CT, multiple-source, and dual-energy CT - actually date back to the early days of CT. We review the historic origins and evolution of these techniques, which may provide some insight into the latest innovations in commercial CT systems. (orig.)

2011-03-01

189

Adiabatic quantum computing with phase modulated laser pulses  

Energy Technology Data Exchange (ETDEWEB)

Implementation of quantum logical gates for multilevel systems is demonstrated through decoherence control under the quantum adiabatic method using simple phase modulated laser pulses. We make use of selective population inversion and Hamiltonian evolution with time to achieve such goals robustly instead of the standard unitary transformation language. (letter to the editor)

2005-09-23

190

ATP-gated P2X3 receptors constitute a positive autocrine signal for insulin release in the human pancreatic ? cell  

UK PubMed Central (United Kingdom)

Extracellular ATP has been proposed as a paracrine signal in rodent islets, but it is unclear what role ATP plays in human islets. We now show the presence of an ATP signaling pathway that enhances...Full Text Available

2010-04-06

191

A simple and continuous on-state current model of polysilicon thin-film transistors for circuit simulation  

Energy Technology Data Exchange (ETDEWEB)

A simple and continuous model for the on-state current of polysilicon thin-film transistors, suitable for implementation in circuit simulators, is presented. The model includes the potential barrier at the grain boundaries, the channel length modulation and the excess current due to impact ionization. Comparison between measured output characteristics and the model shows excellent agreement over wide range of bias voltages and for devices with different gate lengths.

2005-01-01

192

2D cavity grid quantum computing  

Energy Technology Data Exchange (ETDEWEB)

We propose a novel scheme for scalable solid state quantum computing, where superconducting microwave transmission line resonators (cavities) are arranged in a two-dimensional grid on the surface of a chip, coupling to superconducting qubits (charge or flux) at the intersections. We analyze how tasks of quantum information processing can be implemented in such a topology, including efficient two-qubit gates between any two qubits on the grid and elements of fault-tolerant computation.

2008-07-01

193

Natriuretic peptides in vascular physiology and pathology.  

Science.gov (United States)

Four major natriuretic peptides have been isolated: atrial natriuretic peptide (ANP), brain natriuretic peptide (BNP), C-type natriuretic peptide (CNP), and Dendroaspis-type natriuretic peptide (DNP). Natriuretic peptides play an important role in the regulation of cardiovascular homeostasis maintaining blood pressure and extracellular fluid volume. The classical endocrine effects of natriuretic peptides to modulate fluid and electrolyte balance and vascular smooth muscle tone are complemented by autocrine and paracrine actions that include regulation of coronary blood flow and, therefore, myocardial perfusion; modulation of proliferative responses during myocardial and vascular remodeling; and cytoprotective anti-ischemic effects. The actions of natriuretic peptides are mediated by the specific binding of these peptides to three cell surface receptors: type A natriuretic peptide receptor (NPR-A), type B natriuretic peptide receptor (NPR-B), ...

2008-01-01

194

Surface Fermi level engineering: Or there's more to Schottky barriers than just making diodes and field effect transistor gates  

Science.gov (United States)

Surface scientists argue about the fundamental nature of Schottky barriers, or more precisely what determines the location of the Fermi level at semiconductor surfaces and interfaces. Electrical and materials engineers worry about how to make Schottky barrier diodes and gates to field effect transistors and the control of barrier heights. There is some interesting middle ground in which the location of the surface and interface Fermi level can, for example, determine semiconductor doping characteristics during crystal growth. The authors will discuss several interesting and well known examples of doping characteristics which are still somewhat mysterious. Specifically, they address the following question: (1) why is Ge doped GaAs p type when grown from Ga melts but n type when grown from Au melts (2) why is low resistivity p type ZnSe, AlAs, and AlGaInP hard to make, and more importantly, how can the problem be fixed. In addition they describe how this concept ...

195

Quantum computing using molecular electronic and vibrational states  

Energy Technology Data Exchange (ETDEWEB)

We numerically constructed elementary phase-correct global quantum gates by using molecular electronic and vibrational states to encode two qubits and implement the Deutsch-Jozsa algorithm. The calculations were based on optimal control theory (OCT). The molecular species we chose were Na{sub 2} and Li{sub 2}. The electronic X{sup 1}{sigma}{sub g}{sup +} and A{sup 1}{sigma}{sub u}{sup +} states were taken as two orthonormalized energy levels of the electronic qubit. The vibrational qubits were those involved in these electronic states. The time duration of the optimized pulses with high fidelity was typically 500-900 fs, which reflects the wavepacket dynamics in electronically ground and excited states. When implementing the Deutsch-Jozsa algorithm by combining these elementary gates, we obtained a maximum probability 83.12% for Li{sub 2} molecule, which indicates that the electronic-vibrational qubits are worse than the vibrational-vibrational ...

2008-01-22

196

Polysilicon thin film transistors fabricated on low temperature plastic substrates  

Energy Technology Data Exchange (ETDEWEB)

We present device results from polysilicon thin film transistors (TFTs) fabricated at a maximum temperature of 100&hthinsp;{degree}C on polyester substrates. Critical to our success has been the development of a processing cluster tool containing chambers dedicated to laser crystallization, dopant deposition, and gate oxidation. Our TFT fabrication process integrates multiple steps in this tool, and uses the laser to crystallize deposited amorphous silicon as well as create heavily doped TFT source/drain regions. By combining laser crystallization and doping, a plasma enhanced chemical vapor deposition SiO{sub 2} layer for the gate dielectric, and postfabrication annealing at 150&hthinsp;{degree}C, we have succeeded in fabricating TFTs with I{sub ON}/I{sub OFF} ratios {gt}5{times}10{sup 5} and electron mobilities {gt}40 cm{sup 2}/V&hthinsp;s on polyester substrates. {copyright} {ital 1999 American Vacuum Society.}

1999-07-01

197

Effects of DC gate and drain bias stresses on the degradation of excimer laser crystallized polysilicon thin film transistors  

Energy Technology Data Exchange (ETDEWEB)

The effects of gate and drain bias stresses on thin film transistors fabricated in polysilicon films crystallized using the advanced sequential lateral solidification excimer laser annealing (SLS ELA) process, which yields very elongated polysilicon grains and allows the fabrication of TFTs without grain boundary barriers to current flow, are investigated as a function of the active layer thickness and of the TFT orientation relative to the grains. The application of hot carrier stress, with a condition of V{sub GS} = V{sub DS}/2, was determined to induce threshold voltage, subthreshold swing and transconductance degradation for TFTs in thicker polysilicon films and the associated stress-induced increase in the active layer trap density was evaluated. However, this device degradation was drastically reduced for TFTs fabricated in ultra-thin films. Furthermore, the application of the same stress condition to TFTs oriented vertically to the elongated grains resulted ...

2005-01-01

198

Effects of DC gate and drain bias stresses on the degradation of excimer laser crystallized polysilicon thin film transistors  

International Nuclear Information System (INIS)

The effects of gate and drain bias stresses on thin film transistors fabricated in polysilicon films crystallized using the advanced sequential lateral solidification excimer laser annealing (SLS ELA) process, which yields very elongated polysilicon grains and allows the fabrication of TFTs without grain boundary barriers to current flow, are investigated as a function of the active layer thickness and of the TFT orientation relative to the grains. The application of hot carrier stress, with a condition of V_G_S = V_D_S/2, was determined to induce threshold voltage, subthreshold swing and transconductance degradation for TFTs in thicker polysilicon films and the associated stress-induced increase in the active layer trap density was evaluated. However, this device degradation was drastically reduced for TFTs fabricated in ultra-thin films. Furthermore, the application of the same stress condition to TFTs oriented vertically to the elongated grains resulted in ...

2005-01-01

199

Effect of chemical composition of SiOx films on rapid formation of Si nanocrystals induced by thermal plasma jet irradiation  

British Library Electronic Table of Contents (United Kingdom)

Si nanocrystal floating gate MOS capacitors were formed on p-Si (100) wafers by thermal plasma jet (TPJ) annealing of SiO2/SiOx /SiO2/Si(100) stacked structure. The chemical composition of SiOx layer was controlled by changing the SiH4, He, and O2 gas flow ratio during plasma enhanced chemical vapour deposition. The MOS capacitors showed clear hysteresis in capacitance-voltage (CV) characteristics after TPJ annealing. The hysteresis width shows maximum value when initial composition x =1.7, which shows the maximum photoluminescence (PL) intensity. The maximum hysteresis width of 6.8 V was observed with gate voltage swept between 20 and -20 V in x = 1.7 sample. The result means 7.4 x 1012 cm-2 carriers are injected to or emitted from Si nanocrystals. The duration of 1 V shift in flatband vo...

2010-01-01

200

Theoretical considerations for SRAM total-dose hardening  

International Nuclear Information System (INIS)

The theoretical hardness against total dose of the six-transistor SRAM cell is investigated in detail. An explicit analytical expression of the maximum tolerable threshold voltage shift is derived for two cross-coupled inverters. A numerical method is used to explore the hardness of the read and write operations. Both N- and P-channel access transistors designs are considered and their respective advantages are compared. The study points out that the radiation hardness mainly relies on the technology. Results obtained with the very robust Gate-All-Around process are finally presented.

201

Quantum-dot computing  

Energy Technology Data Exchange (ETDEWEB)

A quantum computer would put the latest PC to shame. Not only would such a device be faster than a conventional computer, but by exploiting the quantum-mechanical principle of superposition it could change the way we think about information processing. However, two key goals need to be met before a quantum computer becomes reality. The first is to be able to control the state of a single quantum bit (or 'qubit') and the second is to build a two-qubit gate that can produce 'entanglement' between the qubit states. (U.K.)

2003-10-01

202

Quantum Computing with an Electron Spin Ensemble  

DEFF Research Database (Denmark)

We propose to encode a register of quantum bits in different collective electron spin wave excitations in a solid medium. Coupling to spins is enabled by locating them in the vicinity of a superconducting transmission line cavity, and making use of their strong collective coupling to the quantized radiation field. The transformation between different spin waves is achieved by applying gradient magnetic fields across the sample, while a Cooper pair box, resonant with the cavity field, may be used to carry out one- and two-qubit gate operations.

2009-01-01

203

Integrated photonic qubit quantum computing on a superconducting chip  

International Nuclear Information System (INIS)

We study a quantum computing system using microwave photons in transmission line resonators on a superconducting chip as qubits. We show that linear optics and other controls necessary for quantum computing can be implemented by coupling to Josephson devices on the same chip. By taking advantage of the strong nonlinearities in Josephson junctions, photonic qubit interactions can be realized. We analyze the gate error rate to demonstrate that our scheme is realistic even for Josephson devices with limited decoherence times. As a conceptually innovative solution based on existing technologies, our scheme provides an integrated and scalable approach to the next key milestone for photonic qubit quantum computing.

2010-06-01

204

Effects of avalanche hole injection in fluorinated SiO[sub 2] MOS capacitors  

Energy Technology Data Exchange (ETDEWEB)

Significantly improved immunity to hot-hole damage of the SiO[sub 2]/Si structure is achieved by a shallow fluorine implantation into the poly-Si gate of MOS capacitors followed by a drive-in process. Compared to the nonfluorinated control, the fluorinated samples exhibit a dramatic reduction of both hole trapping probability and interface-trap generation under avalanche hole injection conditions. The degree of such an improvement increases monotonically as a function of the F implantation dose (up to 10[sup 16]/cm[sup 2]). Significant decrease of the hole detrapping rate is also observed in fluorinated samples. Possible mechanisms are discussed.

1993-04-01

205

A practical scheme for error control using feedback  

CERN Document Server

We describe a scheme for quantum error correction that employs feedback and weak measurement rather than the standard tools of projective measurement and fast controlled unitary gates. The advantage of this scheme over previous protocols (for example Ahn et. al, PRA, 65, 042301 (2001)), is that it requires little side processing while remaining robust to measurement inefficiency, and is therefore considerably more practical. We evaluate the performance of our scheme by simulating the correction of bit-flips. We also consider implementation in a solid-state quantum computation architecture and estimate the maximal error rate which could be corrected with current technology.

2004-01-01

206

The neuronal nicotinic acetylcholine receptor {alpha}7 subunit gene: Cloning, mapping, structure, and targeting in mouse  

Energy Technology Data Exchange (ETDEWEB)

The neuronal nicotinic acetylcholine receptor {alpha}7 subunit is a member of a family of ligand-gated ion channels, and is the only subunit know to bind {alpha}-bungarotoxin in mammalian brain. {alpha}-Bungarotoxin binding sites are known to be more abundant in the hippocampus of mouse strains that are particularly sensitive to nicotine-induced seizures. The {alpha}7 receptor is highly permeable to calcium, which could suggest a role in synaptic plasticity in the nervous system. Auditory gating deficiency, an abnormal response to a second auditory stimulus, is characteristic of schizophrenia. Mouse strains that exhibit a similar gating deficit have reduced hippocampal expression of the {alpha}7 subunit. We have cloned and sequenced the full length cDNA for the mouse {alpha}7 gene (Acra-7) and characterized its gene structure. The murine {alpha}7 shares amino acid identity of 99% and 93% with the rat and human {alpha}7 ...

1994-09-01

207

Regional evaluation of the coalbed-methane potential of the Foothills/Mountains of Alberta, Canada  

Energy Technology Data Exchange (ETDEWEB)

Coal is present in the Alberta Foothills/Mountains in five zones: the Kootenay, Gething, Gates, Brazeau and Coalspur coal zones. For coalbed-methane (CBM) evaluation purposes, they can be divided into shallow (less than 1000 m depth) and deep (greater than 1000 m depth) coal zones. The potential gas content of all shallow coal zones totals about 878x10{sup 9} m{sup 3} (31 Tcf) of CBM, which is considered an inferred, initial, in-place, coalbed-methane resource estimate based on limited data. The limited amount of data on formation testing and measured gas content indicate that the inferred resource is bordering on the speculative category. The gas content of all deep coal zones (deeper than 1000 m) totals 2.8x10{sup 12} m{sup 3} (about 99 Tcf) of in-place coalbed-methane gas. Consequently, the total ultimate coalbed-methane resource could be 3.7x10{sup 12} m{sup 3} (130 Tcf). However, coalbed-methane recovery from deep coals is generally not attempted because of ...

2006-01-03

208

Individually weight-adapted examination protocol in retrospectively ECG-gated MSCT of the heart  

Energy Technology Data Exchange (ETDEWEB)

The standard protocol in multislice spiral CT (MSCT) angiography for coronary arteries with fixed tube current-time settings leads to an overexposure and thus to an unnecessary high radiation dose in patients with lower weight when compared to heavier patients. The purpose of this study was to estimate the effect of reducing the radiation dose by adapting the tube current-time settings individually. Fifty patients underwent retrospectively ECG-gated MSCT of the heart. In 25 patients (group A{sub 1}) a standard protocol with constant tube current-time settings was used (4 x 1-mm collimation, 120 kV, 400 mAs{sub eff}). Subsequently, artificial image noise was added to the data of these patients simulating a directive for weight-adapted tube current-time settings (group A{sub 2}). In the other 25 patients (group B) an alternative protocol with individually weight-adapted tube current-time settings was applied. The data of all groups were evaluated by a regression ...

2003-12-01

209

Individually weight-adapted examination protocol in retrospectively ECG-gated MSCT of the heart  

International Nuclear Information System (INIS)

The standard protocol in multislice spiral CT (MSCT) angiography for coronary arteries with fixed tube current-time settings leads to an overexposure and thus to an unnecessary high radiation dose in patients with lower weight when compared to heavier patients. The purpose of this study was to estimate the effect of reducing the radiation dose by adapting the tube current-time settings individually. Fifty patients underwent retrospectively ECG-gated MSCT of the heart. In 25 patients (group A_1) a standard protocol with constant tube current-time settings was used (4 x 1-mm collimation, 120 kV, 400 mAs_e_f_f). Subsequently, artificial image noise was added to the data of these patients simulating a directive for weight-adapted tube current-time settings (group A_2). In the other 25 patients (group B) an alternative protocol with individually weight-adapted tube current-time settings was applied. The data of all groups were evaluated by a regression analysis. The ...

2003-12-01

210

Assessment of left ventricular wall motion by optional multiple long-axial gated blood pool SPECT  

International Nuclear Information System (INIS)

Optional multiple long-axial gated blood pool SPECT images were prepared for the purpose of stereoscopic and quantitative imaging of left ventricular wall motion (LVWM). Sixteen patients with ischemic heart disease and 8 healthy subjects were imaged in 32 views in the 360 degrees position after iv injection of 740 MBq of Tc-99m-labeled human serum albumin D. The R-R interval was divided into 16. After preparing conventional oblique images, long-axial images were prepared. Shortening rate of left ventricular wall was calculated in 5 segments of the apex and base of the left ventricle. An average shortening rate in each segment was graded with a score from a minimum of 0 to a maximum of 40% or more. In the normal group, shortening rate in each segment, except for the base of the septal region, exceeded 40%. In the group of ischemic heart disease, radial shortening was capable of visualizing the degree and extent of the whole LVWM abnormality. LVWM abnormality seen on ...

1991-01-01

211

The role of insulin therapy and glucose normalisation in patients with acute coronary syndrome  

British Library Electronic Table of Contents (United Kingdom)

Patients with acute myocardial infarction (AMI) and diabetes mellitus, as well as patients admitted with elevated blood glucose without known diabetes, have impaired outcome. Therefore intensive glucose-lowering therapy with insulin (IGL) has been proposed in diabetic or hyperglycaemic patients and has been shown to improve survival and reduce incidence of adverse events. The current manuscript provides an overview of randomised controlled trials investigating the effect of IGL. Furthermore, systematic glucose?insulin?potassium infusion (GIK) has been studied to improve outcome after AMI. In spite of positive findings in some early studies, GIK did not show any beneficial effects in recent clinical trials and thus this concept has been abandoned. While IGL targeted to achieve normoglycaemi...

2011-01-01

212

Small heat shock protein 20 (HspB6) in cardiac hypertrophy and failure  

British Library Electronic Table of Contents (United Kingdom)

Hsp20, referred to as HspB6, is constitutively expressed in various tissues. Specifically, HspB6 is most highly expressed in different types of muscle including vascular, airway, colonic, bladder, and uterine smooth muscle; cardiac muscle; and skeletal muscle. It can be phosphorylated at Ser-16 by both cAMP- and cGMP-dependent protein kinases (PKA/PKG). Recently, Hsp20 and its phosphorylation have been implicated in multiple physiological and pathophysiological processes including smooth muscle relaxation, platelet aggregation, exercise training, myocardial infarction, atherosclerosis, insulin resistance and Alzheimer's disease. In the heart, key advances have been made in elucidating the significance of Hsp20 in contractile function and cardioprotection over the last decade. This mini-rev...

2011-01-01

213

Progress and problems in the chemistry of technetium-99m tracers  

International Nuclear Information System (INIS)

The recent acceleration of effort to elucidate and explore the coordination chemistry of technetium has been prompted mainly by the need for a new generation of radiotracers in nuclear medicine, preferentially for tomograhic studies. Current approaches and their limitations in designing "9"9"mTc complexes capable of penetrating cell membranes of the target organs, and remaining there sufficiently long, are reviewed. With the predominance of Tc(V) oxo compounds, especially for brain imaging agents, new N4 and N2S2 coordinate complexes have been developed by shifting from bidentate to tetradentate ligands with a variable side chain or other adjustable reactivity. The search for myocardial imaging agents has focused on a variety of mixed ligand complexes of Tc(III) and most promising [Tc(CNR)_6]"+ complexes of Tc(I). 64 refs. (author).

214

Myocardial pharmacokinetics of ebastine, a substrate for cytochrome P450 2J, in rat isolated heart  

British Library Electronic Table of Contents (United Kingdom)

BACKGROUND AND PURPOSE It is well established that cytochrome P450 2J (CYP2J) enzymes are expressed preferentially in the heart, and that ebastine is a substrate for CYP2J, but it is not known whether ebastine is metabolized in myocardium. Therefore, we investigated its pharmacokinetics in the rat isolated perfused heart. EXPERIMENTAL APPROACH Rat isolated hearts were perfused in the recirculating mode with ebastine for 130-min. The concentrations of ebastine and its metabolites, hydroxyebastine and carebastine, were measured using liquid chromatography with a tandem mass spectrometry. The data were analysed by a compartmental model. The time course of negative inotropic response was linked to ebastine concentration to determine the concentration-effect relationship. KEY RESULTS Ebastine w...

2011-01-01

215

Clinical Evaluation of the Zilver Vascular Stent for Symptomatic Iliac Artery Disease  

British Library Electronic Table of Contents (United Kingdom)

PurposeTo evaluate the safety and effectiveness of the Zilver vascular stent in the treatment of de novo or restenotic lesions in the external and common iliac arteries.Materials and MethodsRegardless of the results of an initial percutaneous transluminal angioplasty (PTA), 151 consecutive patients were implanted with Zilver vascular stents (Cook, Bloomington, Ind) in up to two stenotic (?10 cm) or occluded (?5 cm) atherosclerotic lesions of the external or common iliac arteries. The primary endpoint was the rate of major adverse events within 9 months after the procedure. Major adverse events were defined as death, myocardial infarction, target lesion revascularization, and limb loss. Secondary endpoints included acute procedural success, 30-day clinical success, 9-month pat...

2008-01-01

216

Chronic sympathetic activation promotes downregulation of ?-adrenoceptor-mediated effects in the guinea pig heart independently of structural remodeling and systolic dysfunction  

British Library Electronic Table of Contents (United Kingdom)

It is uncertain if downregulation of ?-adrenoceptor signaling pathway is promoted by an enhanced adrenergic tone at an early stage of cardiac disease, or it develops secondary to detrimental local myocardial changes in advanced heart failure. We examined the integrity of ?-adrenoceptor signaling pathway upon chronic infusion of isoproterenol, a ?-adrenoceptor agonist, at a dose producing no structural left ventricular (LV) remodeling and systolic dysfunction. Subcutaneous isoproterenol infusion (400??g?kg?1?h?1 over 16?days) to guinea pigs using osmotic minipumps produced no change in cardiac weights, LV internal dimensions, myocyte cross-sectional area, extent of interstitial fibrosis, and basal contractile function. Isolated, perfused heart preparations from isoproterenol-treated guinea ...

2011-01-01

217

Chronic inflammation and mortality in haemodialysis: effect of different renal replacement therapies. Results from the RISCAVID study  

British Library Electronic Table of Contents (United Kingdom)

Background. The `RISchio CArdiovascolare nei pazienti afferenti all' Area Vasta In Dialisi (RISCAVID) study is an observational and prospective trial including the whole chronic haemodialysis (HD) population in the northwest part of Tuscany (1.235 million people). The aim of the study was to elucidate the relevance of traditional and non-traditional risk factors of mortality and morbidity in HD patients as well as the impact of different HD modalities.Methods. A total of 757 HD patients (mean age 66 +- 14 years, mean dialytic age 70 +- 76 months, diabetes 19%) were prospectively followed up for 30 months and all-cause mortality, cardiovascular (CV) mortality and non-fatal CV events (acute myocardial infarction and stroke) were registered. At the time of the enrolment, demographic, clinical...

2008-01-01

218

Aspirin Use Is Associated With an Improved Long-Term Survival in an Unselected Population Presenting With Unstable Angina  

British Library Electronic Table of Contents (United Kingdom)

AbstractBackground Few published data are available on the benefits of aspirin use in patients with unstable angina (UA). Hypothesis Aspirin use carries a mortality benefit in a population-based cohort of patients presenting with UA. Methods All residents of Olmsted County, Minnesota presenting to local emergency departments with acute chest pain from January 1985 through December 1992 having symptoms consistent with UA were identified through medical records. A total of 1628 patients were identified with UA and were stratified by aspirin use in-hospital and at discharge. Cardiovascular mortality and nonfatal myocardial infarction and stroke were assessed over a median of 7.5 years follow-up and all-cause mortality data over a median of 16.7 years. The mean age of patients with UA was 65 y...

2010-01-01

219

As time goes by? The fallacy of thrombolysis in STEMI networks  

British Library Electronic Table of Contents (United Kingdom)

Primary percutaneous coronary intervention (PPCI) is superior to thrombolysis (TL) as reperfusion therapy in ST-elevation myocardial infarction (STEMI). TL is a rapidly available, but semi-effective therapy (effective reperfusion in 50% of patients only), whereas PPCI is a potentially delayed, but highly effective therapy (effective reperfusion in >90%). Since TL loses its efficacy beyond 2?3?h after symptom onset, it is a significant reperfusion alternative to PPCI in early presenters only. The individual decision to treat an early presenter with PPCI or TL requires the evaluation of the time delay between potential start of TL or PPCI, the PCI-related delay (PRD). PRD is greatest, if TL is given in the prehospital setting. Until now, prehospital TL as the most rapidly available reperfusi...

2011-01-01

220

Arterial and venous thrombosis in patients with von Willebrand?s disease: A critical review of the literature  

British Library Electronic Table of Contents (United Kingdom)

All patients with von Willebrand?s disease (vWD) who showed an arterial or venous thrombosis and were reported in the literature have been evaluated. 11 patients had arterial thrombosis while 19 had venous thrombosis for a total of 30 cases. 9 out the 11 cases with arterial thrombosis had myocardial infarction. Two had cerebral thrombosis. Associated risk factors for arterial thrombosis were available only for three patients who showed, respectively, smoking and dyslipidemia (2 cases) and smoking and intravenous desmopressin infusion (1 case). The majority of patients with venous thrombosis showed DVT with or without PE. Four patients presented with apparently isolated PE. In two instances thrombosis occurred in unusual sites (central retinal vein and portal vein, respectively). Several as...

2006-01-01

221

The influence of different SPECT reconstruction algorithms on cardiac ischemia with the use artificial neural networks  

International Nuclear Information System (INIS)

The aim of the study was the attempt to evaluate the influence of two different methods of cardiac perfusion SPECT reconstruction (FBP and ITW) on clinical efficacy in diagnosing the coronary artery disease as well as the cardiac ischemia detection in three areas of heart vascularized by main coronary arteries: LAD, LCX and RCA with the use of artificial neural networks (ANN). The study was performed retrospectively with the use of the diagnostic image records as well as clinical dataset of 43 patients. Myocardial perfusion stress/rest SPECT study and X-ray coronarography data were evaluated for each patient. The results of coronary angiography were considered the reference method. The cardiac SPECT data were reconstructed using the two different methods: filtered backprojection (FBP) and iterative Wallis method (ITW). The local perfusion deficits denominated in stress and rest study in three main vessel cardiac segments were the main input values for the ANN. The ...

222

Swimming exercise training prior to acute myocardial infarction attenuates left ventricular remodeling and improves left ventricular function in rats.  

Science.gov (United States)

The effect of exercise training prior to acute myocardial infarction (AMI) on left ventricular (LV) remodeling is poorly understood. This study investigated the protective effect of 3 weeks of swimming exercise training prior to AMI on cardiac morphology and function. Male Sprague-Dawley rats (n = 35) were randomly assigned to 3 groups: swimming training (n = 14, 90 min, 5 days/wk, 3 wk), sedentary (n =14), and controls (n = 7, no exercise, no MI). At the end of the training/sedentary period, rats were subjected to AMI (ExMI and SedMI) induced by surgical ligation of the left coronary artery. Thereafter, the rats remained sedentary for a 4-wk recovery period. Trans-thoracic echocardiography was performed in each group at the end of the exercise/sedentary period (pre-AMI), 24 hr after AMI, and following recovery (4 wk after AMI). No differences were observed in LV dimensions and function pre-AMI among the 3 groups; however, LV-end systolic diameter (LVESD) and ...

2005-01-01

223

Nuclear medicine progress report for quarter ending March 31, 1985  

Energy Technology Data Exchange (ETDEWEB)

Radioiodinated 15-(p-iodophenyl)-3,3-dimethylpentadecanoic acid (DMIPP) has been prepared as a new terminal iodophenyl-substituted fatty acid containing dimethyl-branching at the beta-position. Iodine-125-labeled DMIPP showed rapid, high myocardial uptake (min, mean % injected dose/g) in fasted rats (5, 4.67; 30, 5.06; 60, 4.79; 120, 4.37), and also exhibited high heart:blood ratios (min, ratio) 5, 3:1; 30, 12:1; 60, 12:1; 120, 13:1. These data demonstrate an unanticipated much longer myocardial residence time with DMIPP (+/sub 1/2/ 7-8 h) than observed with either the 3-monomethyl (BMIPP) analogue (+/sub 1/2/ 30-45 min) or the rapidly metabolized straight-chain (IPP) analogue (+/sub 1/2/ 10-15 min). The (/sup 123/I)DMIPP is thus an excellent candidate for clinical evaluation of regional fatty acid metabolism under conditions where the uptake of energy substrates can be assessed independent of regional blood delivery. Studies with the new ...

1985-07-01

224

Cold pressor test myocardial perfusion SPECT as a predictor of the development of ischemia at exercise in the follow up of asymptomatic patients with moderate cardiovascular risk  

International Nuclear Information System (INIS)

Introduction: Previous studies have published the correlation between myocardial perfusion SPECT (MP) during cold pressor test (CPT) and intracoronary acetylcholine and its usefulness as independent marker of endothelial dysfunction (ED). Objective: To analyze the incidence of positivization of MP exercise studies in the follow up of asymptomatic patients with moderate cardiovascular risk (CV) and ED detected by PF. Material and Methods: Of 301 patients of the PARADIGMA Registry (normal exercise MP SPECT and clinical probability < 20% of events at 10 years [moderate risk by Framingham index]) 55 had positive PF (+) (18.3%). Prospectively and consecutively, 15 asymptomatic patients with PF (+), and a control group (CG) of 15 patients with negative PF, with paired sex, age and coronary risk factors (CRF), that accomplished a 12 #+-# 2 months follow up, and that underwent a new exercise and resting MP SPECT were analyzed. An MP extension score was used in a model ...

225

Wind turbulence estimates in a valley by coherent Doppler lidar  

British Library Electronic Table of Contents (United Kingdom)

Abstract In this paper, the effect of several turbulence parameters during various flow conditions in Owens Valley, educed from coherent Doppler lidar data have been studied. Radial velocity structure functions are processed to estimate the turbulent kinetic energy (TKE) dissipation rate, integral length scale and velocity variance, assuming a theoretical model for isotropic wind fields. Corrections for turbulence measurements have been considered to address the complications due to inherent volumetric averaging of radial velocity over each range gate, noise of the lidar data, and the assumptions required to estimate effects of smaller scales of motion on turbulence quantities. Using data from the Terrain-induced Rotor Experiment (T-REX) in April-May 2006, vertical profiles of wind and tur...

2011-01-01

226

Training aids: the motor operator valve trainer  

International Nuclear Information System (INIS)

The spectrum of training aids used in the nuclear industry runs the gamut from the very basic (i.e., valve training aids - gate, globe, check) to the highly complex (i.e., nuclear full scope simulator). Designing and purchasing the best training aids take much time, detailed investigation, and good understanding of plant operations. The training aid that has given the New York Power Authority the best results has been the motor operator valve (MOV) trainer. Some of the items that make the MOV trainer a good choice are: (1) large number of MOVs in the plant, (2) importance of MOVs to safe plant operation, (3) detailed MOV procedures used by the plant, (4) history of MOV problems, and (5) ability to demonstrate important concepts and operation - hammer blow effect, torque and limit switch adjustment and functions, and actual sequence of operation of the limitorque valve operator.

1987-06-07

227

Targeting the nicotinic alpha7 acetylcholine receptor to enhance cognition in disease  

British Library Electronic Table of Contents (United Kingdom)

A promising drug target currently under investigation to improve cognitive deficits in neuropsychiatric and neurological disorders is the neuronal nicotinic alpha7 acetylcholine receptor (a7nAChR). Improving cognitive impairments in diseases such as Alzheimer's (AD) and schizophrenia remains a large unmet medical need, and the a7nAChR has many properties that make it an attractive therapeutic target. The a7nAChR is a ligand gated ion channel that has particularly high permeability to Ca^2^+ and is expressed in key brain regions involved in cognitive processes (e.g., hippocampus). The a7nAChRs are localized both pre-synaptically, where they can regulate neurotransmitter release, and post-synaptically where they can activate intracellular signaling cascades and influence downstream processes...

2011-01-01

228

Stepping, Strain Gating, and an Unexpected Force-Velocity Curve for Multiple-Motor-Based Transport  

British Library Electronic Table of Contents (United Kingdom)

SummaryBackground Intracellular transport via processive kinesin, dynein, and myosin molecular motors plays an important role in maintaining cell structure and function. In many cases, cargoes move distances longer than expected for single motors; there is significant evidence that this increased travel is in part due to multiple motors working together to move the cargoes. Although we understand single motors experimentally and theoretically, our understanding of multiple motors working together is less developed. Results We theoretically investigate how multiple kinesin motors function. Our model includes stochastic fluctuations of each motor as it proceeds through its enzymatic cycle. Motors dynamically influence each other and function in the presence of thermal noise and viscosity. We...

2008-01-01

229

Spin qubits in antidot lattices  

DEFF Research Database (Denmark)

We suggest and study designed defects in an otherwise periodic potential modulation of a two-dimensional electron gas as an alternative approach to electron spin based quantum information processing in the solid-state using conventional gate-defined quantum dots. We calculate the band structure and density of states for a periodic potential modulation, referred to as an antidot lattice, and find that localized states appear, when designed defects are introduced in the lattice. Such defect states may form the building blocks for quantum computing in a large antidot lattice, allowing for coherent electron transport between distant defect states in the lattice, and for a tunnel coupling of neighboring defect states with corresponding electrostatically controllable exchange coupling between different electron spins.

2008-01-01

230

Plasma Diagnostics in the Optical and X-ray regions on the Plasma Focus device PF-4 (Installation TYULPAN)  

International Nuclear Information System (INIS)

The results of experiments received on the plasma focus (PF) device with energy stored equal 4 kJ are represented. Photos of the current plasma sheath (CPS), pre-pinch, sphere-like plasma formations are produced with help of the electron-optical converter contained a gated micro-channel plate (MCP) and the CCD-camera imaging system in the visible region. The redial velocity of the CPS is about 107 cm/s. Neon plasma electron density measured with help of the interferograms in the visible region and the spectra in the soft X-ray region is equals to 3?1018 cm-3. Electron temperature is equal to about 200 eV. Discharge integral photos were obtained with help of the soft X-ray pinhole camera. Pictures with 2 ?s resolution of the plasma luminescence above PF anode region were made by CCD-camera.

2006-01-01

231

Ozone production process in pulsed positive dielectric barrier discharge  

International Nuclear Information System (INIS)

The ozone production process in a pulsed positive dielectric barrier discharge (DBD) is studied by measuring the spatial distribution of ozone density using a two-dimensional laser absorption method. DBD occurs in a 6 mm point-to-plane gap with a 1 mm-thick glass plate placed on the plane electrode. First, the propagation of DBD is observed using a short-gated ICCD camera. It is shown that DBD develops in three phases: primary streamer, secondary streamer and surface discharge phases. Next, the spatial distribution of ozone density is measured. It is shown that ozone is mostly produced in the secondary streamer and surface discharge, while only a small amount of ozone is produced in the primary streamer. The rate coefficient of the ozone production reaction, O + O_2 + M #-># O_3 + M, is estimated to be 2.5 x 10"-"3"4 cm"6 s"-"1.

2007-01-07

232

Numerical simulations of nucleate boiling in impinging jets: Applications in power electronics cooling  

Energy Technology Data Exchange (ETDEWEB)

Boiling jet impingement cooling is currently being explored to cool power electronics components. In hybrid vehicles, inverters are used for DC-AC conversion. These inverters involve a number of insulated-gate bipolar transistors (IGBTs), which are used as on/off switches. The heat dissipated in these transistors can result in heat fluxes of up to 200 W/cm{sup 2}, which makes the thermal management problem quite important. In this paper, turbulent jet impingement involving nucleate boiling is explored numerically. The framework for these computations is the CFD code FLUENT. For nucleate boiling, the Eulerian multiphase model is used. The numerical results for boiling water and R113 jets (submerged) are validated against existing experimental data in the literature. Some representative IGBT package simulations that use R134a as the cooling fluid are also presented. (author)

2008-01-15

233

Low-temperature polysilicon thin-film transistors fabricated from laser-processed sputtered-silicon films  

Energy Technology Data Exchange (ETDEWEB)

In an effort to develop a simple low-temperature high-performance polysilicon thin-film transistor (TFT) technology, the authors report a fabrication process featuring laser-crystallized sputtered-silicon films. This top Al-gate coplanar TFT process subjects the substrate to a maximum temperature of 300 C, and produces devices with mobilities up to 450 cm{sup 2}/Vs, on/off current ratios greater than 10{sup 7}, without using a post-hydrogenation step. They believe these results represent the highest performance TFT`s to date fabricated from sputtered silicon films.

1998-09-01

234

Levels in sup 152 Gd and sup 152 Sm populated by the decay of sup 152 Eu  

Energy Technology Data Exchange (ETDEWEB)

The energy level schemes of {sup 152}Gd and {sup 152}Sm have been established on the basis of single gamma-spectra, and gamma-gamma coincidence measurements. Ge(Li) detectors were used to study the gamma spectra produced in the EC/beta{sup +} and beta{sup -} decays of {sup 152}Eu to {sup 152}Sm and {sup 152}Gd, respectively. Thirteen new transitions are reported and data from eleven coincidence gates enabled five new levels to be suggested. Relative intensities and log ft values were calculated and spin/parities deduced. Comparisons are made with new predictions of the Interacting Boson Model. (orig.).

1990-01-01

235

Levels in "1"5"2Gd and "1"5"2Sm populated by the decay of "1"5"2Eu  

International Nuclear Information System (INIS)

The energy level schemes of "1"5"2Gd and "1"5"2Sm have been established on the basis of single #gamma#-spectra, and #gamma#-#gamma# coincidence measurements. Ge(Li) detectors were used to study the gamma spectra produced in the EC/#beta#"+ and #beta#"- decays of "1"5"2Eu to "1"5"2Sm and "1"5"2Gd, respectively. Thirteen new transitions are reported and data from eleven coincidence gates enabled five new levels to be suggested. Relative intensities and log ft values were calculated and spin/parities deduced. Comparisons are made with new predictions of the Interacting Boson Model. (orig.).

1990-01-01

236

Implementation of an OFDM underwater acoustic communication system on an underwater vehicle with multiprocessor structure  

British Library Electronic Table of Contents (United Kingdom)

Orthogonal frequency division multiplexing (OFDM) can fully use the frequency band and transmit data at high speeds. The ADSP-TS101 is a high performance digital signal processor (DSP) with good properties that include parallel processing and a high speed. Aimed at the real-time processing requirement of the OFDM algorithm, an underwater acoustic communication system with real-time processing capability is carried out. The system is mainly composed of multiple ADSP-TS101s, a multi-channel synchronous sample module and a field programmable gate array (FPGA) chip. The multiprocessor structure is made up of a cluster/data flow associated multiprocessing parallel processing structure as the operation kernel, and a multi-channel synchronous sample module is designed to realize no phase warp amo...

2007-01-01

237

Genomic survey of prepulse inhibition in mouse chromosome substitution strains  

British Library Electronic Table of Contents (United Kingdom)

Prepulse inhibition (PPI) is a measure of sensorimotor gating, a pre-attentional inhibitory brain mechanism that filters extraneous stimuli. Prepulse inhibition is correlated with measures of cognition and executive functioning, and is considered an endophenotype of schizophrenia and other psychiatric illnesses in which patients show PPI impairments. As a first step toward identifying genes that regulate PPI, we performed a quantitative trait locus (QTL) screen of PPI phenotypes in a panel of mouse chromosome substitution strains (CSSs). We identified five CSSs with altered PPI compared with the host C57BL/6J strain: CSS-4 exhibited decreased PPI, whereas CSS-10, -11, -16 and -Y exhibited higher PPI compared with C57BL/6J. These data indicate that A/J chromosomes 4, 10, 11, 16 and Y harbor...

2009-01-01

238

Flow-induced changes in pial artery compliance registered with a non-invasive method in rabbits  

British Library Electronic Table of Contents (United Kingdom)

Aim: This study was performed: 1) to assess the relationship between blood flow velocity in the internal carotid artery (CBFICA) and pial artery pulsation (cc-TQ) and 2) to evaluate flow-induced changes in pial artery compliance. Methods: Experiments were performed on 10 crossbred male rabbits. Heart rate (HR), blood pressure (BP), left ventricle ejection fraction (LVEF), CBFICA, the systolic-diastolic blood volume fraction in the brain circulation (CBFSDF) and cc-TQ were recorded after glucagon and acetazolamide administration. cc-TQ was measured with near-infrared transillumination back scattering sounding (NIR-T/BSS), LVEF and CBFSDF with gated scintigraphy and BP and CBFICA with electromagnetic pressure and flow transducers, respectively. Doses of drugs were chosen to exert a haemodyna...

2011-01-01

239

Exogenous nicotine normalises sensory gating in schizophrenia; therapeutic implications  

British Library Electronic Table of Contents (United Kingdom)

Summary There is a current popular recognition that cigarette smoking is deleterious to health. Although this is very clearly the case for physical health, the situation regarding mental health is, however, rather more complicated. This piece concentrates on the role of smoking in schizophrenia: it is important to consider why schizophrenia, exceptionally amongst the severe and enduring mental illnesses, is associated with increased cigarette consumption. People who suffer from schizophrenia consequently have a greater risk of the complications to physical health caused by this addiction and clearly, it is important to understand why this occurs. Numerous investigators have found that both neuroleptic-naive, first-onset schizophrenics, together with chronic sufferers of the illness, consum...

2009-01-01

240

Effects on focused ion beam irradiation on MOS transistors  

Energy Technology Data Exchange (ETDEWEB)

The effects of irradiation from a focused ion beam (FIB) system on MOS transistors are reported systematically for the first time. Three MOS transistor technologies, with 0.5, 1, and 3 {mu}m minimum feature sizes and with gate oxide thicknesses ranging from 11 to 50 nm, were analyzed. Significant shifts in transistor parameters (such as threshold voltage, transconductance, and mobility) were observed following irradiation with a 30 keV Ga{sup +} focused ion beam with ion doses varying by over 5 orders of magnitude. The apparent damage mechanism (which involved the creation of interface traps, oxide trapped charge, or both) and extent of damage were different for each of the three technologies investigated.

1997-04-01

241

Development of linear flow rate control system for eccentric butter-fly valve  

Energy Technology Data Exchange (ETDEWEB)

Butter-fly valves are advantageous over gate, globe, plug, and ball valves in a variety of installations, particularly in the large sizes. The purpose of this project development of linear flow rate control system for eccentric butter-fly valve (intelligent butter-fly valve system). The intelligent butter-fly valve system consist of a valve body, micro controller. The micro controller consist of torque control system, pressure censor, worm and worm gear and communication line etc. The characteristics of intelligent butter-fly valve system as follows: Linear flow rate control function. Digital remote control function. guard function. Self-checking function. (author)

1999-12-01

242

Design: voice activated door opener.  

Science.gov (United States)

A voice activated garage door opener was designed for a handicapped person to open a garage door without assistance. This design uses speech recognition of one word. The activating word that was chosen is "up". The frequency spectrum of "up" was captured on a soundboard and is the basis of this design. Filters are used to pick out three frequency bands in this spectrum. The output signals from these filters are then compared to three threshold voltages using voltage comparators. If the output signals from the filters are above the threshold voltages, the comparators go high. Monostable multivibrators are used on the output of the comparators to lengthen the high pulses. When all of the pulses from the monostable multivibrators are high at the same time, an AND gate output goes high. This high pulse activates the door opener. PMID:8329601

1993-01-01

243

Delayed Afterdepolarization in Intact Canine Sinoatrial Node as a Novel Mechanism for Atrial Arrhythmia  

British Library Electronic Table of Contents (United Kingdom)

Delayed Afterdepolarization in Sinoatrial Node. Introduction: Recent evidence indicates that spontaneous sarcoplasmic reticulum Ca release and Na-Ca exchanger current activation contribute to the sinoatrial node (SAN) automaticity. These findings suggest that SAN activity may share mechanisms that underlie both automaticity and triggered activity. The aim of this study is to test the hypothesis that spontaneous, nonvoltage gated, intracellular Ca (Cai) elevation may induce delayed afterdepolarization (DAD) in intact SAN during isoproterenol infusion. Methods and Results: We simultaneously mapped Cai and membrane potential in 31 isolated Langendorff-perfused canine right atriums (RA). Isoproterenol increased heart rate and late diastolic Cai elevation (LDCAE) of the superior SAN, leading to...

2011-01-01

244

Challenges in presenting high dimensional data to aid in triage in the DARPA virtual soldier project.  

Science.gov (United States)

One of the goals of the DARPA Virtual Soldier Project is to aid the field medic in the triage of a casualty. In Phase I, we are currently collecting 12 baseline experimental physiological variables and a cardiac gated Computed Tomography (CT) imagery for use in an prototyping a futuristic electronic medical record, the "Holomer". We are using physiological models and Kalman filtering to aid in diagnosis and predict outcomes in relation to cardiac injury. The physiological modeling introduces another few hundred variables. Reducing the complexity of the above into easy-to-read text to aid in the triage by the field medic is the challenge with multiple display solutions. A description of the possible techniques follows. PMID:15718701

2005-01-01

245

Cardiac transplantation. Value of computed tomography  

International Nuclear Information System (INIS)

In 9 over 12 patients who underwent cardiac transplantation computed tomography was performed. In 5 of them CT was obtained also before the surgical treatment. In all patients angio-CT technique was performed, while the ECG-gated technique was employed only before surgery. CT shows changes in morphology of both atria but over all of the right one, and rotation of the heart on the longitudinal axis. The conditions of the pericardium are particulary well demonstrated: in 5 cases pericardial effusion was observed, 3 times localized and 2 times diffuse. Only in 1 patient a small thrombus in the right atrium was demonstrated. CT allows the possibility to obtain simultaneously information on mediastinum, lung and pleura. Pleural effusion, pulmonary infections and mediastinal complications are easily demonstrated.

1986-01-01

246

Analysis of self-heating related instability in n-channel polysilicon thin film transistors fabricated on polyimide  

Energy Technology Data Exchange (ETDEWEB)

In this work, we investigated self-heating related instability in polysilicon thin film transistors (poly-Si TFTs) fabricated on polyimide (PI) substrates. Indeed, when Joule heating becomes relevant, the temperature of the active layer can substantially rise, since the devices are fabricated on thermally insulating substrates. As a result, electrical instability is triggered and attributed to the generation of interface states, due to the Si-H bond breaking, and charge trapping into the gate insulator. In addition, by using 3-dimensional numerical simulations, coupling the thermodynamic and transport models, we analyzed the temperature distribution of the device under operating conditions and found that self-heating is more severe for devices fabricated on plastic substrates.

2009-10-01

247

An algebraic approach to linear-optical schemes for deterministic quantum computing  

Energy Technology Data Exchange (ETDEWEB)

Linear-optical passive (LOP) devices and photon counters are sufficient to implement universal quantum computation with single photons, and particular schemes have already been proposed. In this paper we discuss the link between the algebraic structure of LOP transformations and quantum computing. We first show how to decompose the Fock space of N optical modes in finite-dimensional subspaces that are suitable for encoding strings of qubits and invariant under LOP transformations (these subspaces are related to the spaces of irreducible unitary representations of U (N). Next we show how to design in algorithmic fashion LOP circuits which implement any quantum circuit deterministically. We also present some simple examples, such as the circuits implementing a cNOT gate and a Bell state generator/analyser.

2005-12-01

248

Adaptive Management of Liver Cancer Radiotherapy  

British Library Electronic Table of Contents (United Kingdom)

Adaptive radiation therapy for liver cancer has the potential to reduce normal tissue complications and enable dose escalation, allowing the potential for tumor control in this challenging site. Using adaptive techniques to tailor treatment margins to reflect patient-specific breathing motions and image-guidance techniques can reduce the high dose delivered to surrounding normal tissues while ensuring that the prescription dose is delivered to the tumor. Several treatment planning and delivery techniques have been developed for use in the liver, including a margin to encompass the full breathing motion, mean position techniques, which evaluate the probability of tumor location during breathing, breath hold, gating, and tracking. Patient selection, clinical workflow, and quality assurance m...

2010-01-01

249

A novel EPROM device fabricated using focused boron ion-beam implantation  

Energy Technology Data Exchange (ETDEWEB)

A novel floating-gate avalanche injection (FAMOS) type erasable programmable read-only memory (EPROM) device is demonstrated, with a heavily focused ion-beam (FIB) implanted region of about 0.2-..mu..m width at the drain edge of the channel. This heavily B/sup +/-doped region permits a higher electric field near the drain edge, resulting in a remarkable increase of the hot-carrier generation rate, and reduces both the programming voltage and programming time. A three-dimensional device simulator, CADDETH, predicted that the electric field at the drain edge would increase by about six times, which would lead to hot-carrier generation efficiency three orders of magnitude higher.

1987-06-01

250

{sup 99m}TC tetrofosmin cardiac tomography after nitrate administration in patients with coronary artery disease and left ventricular dysfunction; Tomografia cardiaca {sup 99m}Tc tetrofosmina dopo somministrazione di nitrati in pazienti con cardiopatia ischemica e disfunzione ventricolare sinistra  

Energy Technology Data Exchange (ETDEWEB)

The work examines twenty-two patients with coronary artery disease, previous myocardial infarction and LV dysfunction, using the technetium-99m ({sup 99m}Tc) tetrofosmin (SPECT) associated with nitrate administration in the detection of hypoperfused but still viable myocardium. The method allows the detection of this disease. [Italian] Il lavoro analizza i risultati degli esami condotti su 22 pazienti con cardiopatia ischemica cronica e ridotta funzione ventricolare sinistra sottoposti a tomografia computerizzata con emissione di fotone singolo (SPECT) cardiaca con tecnezio-99m ({sup 99m}Tc) tetrofosmina associata alla somministrazione di nitrati nella differenziazione tra tessuto miocardico ipoperfuso ma ancora vitale e tessuto miocardico necrotico. La metodologia usata consente di identificare la presenza di tessuto miocardico vitale in territori vascolari severamente ipoperfusi.

2000-04-01

251

[Natriuretic peptides--relevance in intensive care].  

Science.gov (United States)

The family of natriuretic peptides consists of the atria natriuretic peptide (ANP), the cerebral natriuretic peptide (BNP), the type C natriuretic peptide (CNP) and the peptide isolated from the dendroaspis snakes' poison (DNP), whose presence in humans has not been confirmed. The physiological function of ANP is in the control of arterial blood pressure by regulation of systemic vascular resistance of blood vessels. BNP is produced as one of the factors in the acute response to inflammatory tissue damage, mainly in coronary vessels. Increased serum concentrations of natriuretic peptides have been found in stress situations, such as trauma or major surgery, systemic hypotension, and in intrinsic myocardial dysfunction. High concentrations of natriuretic peptides were observed in severe sepsis, septic shock and in multiple organ failure, probably due to increased secretion by mediators of the inflammatory process.The highest concentrations of ANP and BNP were found ...

252

Routine upfront abciximab versus standard periprocedural therapy in patients undergoing primary percutaneous coronary intervention for cardiogenic shock: The PRAGUE-7 Study. An open randomized multicentre study  

British Library Electronic Table of Contents (United Kingdom)

Background: The outcome of acute myocardial infarction (AMI) complicated with cardiogenic shock is poor. The aim of this study was to analyse, whether upfront abciximab administration could improve the outcomes of cardiogenic shock. Methods: This multicentre open trial randomized 80 patients with AMI complicated by cardiogenic shock expected to undergo primary PCI into group A (routine upfront-pre-procedural-abciximab bolus followed by 12-h abciximab infusion) and group B (standard therapy). The study primary objective was 30-day combined outcome (death/reinfarction/stroke/new severe renal failure). Results: PCI was technically successful in 90% (A) versus 87.5% (B) patients. Abciximab was used in 100% (A) versus 35% (B). The primary endpoint occurred in 17 group A patients (42.5%) and 11 ...

2011-01-01

253

Natriuretic peptides in the pathophysiology of congestive heart failure.  

Science.gov (United States)

A hallmark of congestive heart failure (CHF) is the activation of the cardiac endocrine system, in particular atrial natriuretic peptide (ANP) and brain natriuretic peptide (BNP). The natriuretic peptides are a group of structurally similar but genetically distinct peptides that have diverse actions in cardiovascular, renal, and endocrine homeostasis. ANP and BNP are of myocardial cell origin and C-type natriuretic peptide (CNP) is of endothelial origin. ANP and BNP bind to the natriuretic peptide-A receptor (NPR-A), which, via 3',5'-cyclic guanosine monophosphate (cGMP), mediates natriuresis, vasodilatation, renin inhibition, antimitogenesis, and lusitropic properties. CNP lacks natriuretic actions but possesses vasodilating and growth inhibiting actions via the guanylyl cyclase-linked natriuretic peptide-B receptor. All three peptides are cleared by the natriuretic peptide-C receptor and degraded by the ectoenzyme neutral endopeptidase 24.11, both of which are ...

2000-05-01

254

MRI in the diagnosis of non-compacted ventricular Myocardium (NCVM) compared to echocardiography; MR-Tomographie in der morphologischen Darstellung der isolierten non-compaction des linksventrikulaeren Myokards (NCVM)  

Energy Technology Data Exchange (ETDEWEB)

Purpose: To report the detection of con-compacted ventricular myocardium (NVCM) with MRI compared to echocardiography in 8 patients. Material and methods: Non-compaction of the ventricular myocardium is a congenital disorder characterized by an altered structure of the myocardial wall resulting from an intrauterine arrest in endomyocardial embryogenesis. The morphological findings consist of a prominent meshwork of multiple myocardial trabeculations and deep intertrabecular recesses, communicating with the left ventricular cavity. 8 consecutive patients (mean age 7.3 years) with clinical and echocardiographic signs of NCVM were examined by MRI (1.5 T, Vision, Siemens) in short axis and 2- and 4-chamber views, using T{sub 1}-weighted TSE and Cine-GRE in 6 patients and true FISP sequences in 2 patients. MRI and echocardiography were evaluated for visibility, signs of NCVM and involvement of myocardial wall segments. Thickness ...

2003-09-01

255

Animal and human studies of a new /sup 99m/Tc labelled phosphine-isocyanide complex with possible applications to radionuclide ventriculography  

Energy Technology Data Exchange (ETDEWEB)

A new /sup 99m/Tc-phosphine-isocyanide complex with the general structure (/sup 99m/Tc (DEPE)/sub 2/(CNR)/sub 2/)/sup +/ has been synthesised and tested in animals and one human. In three animal species (rat, rabbit, dog), the complex is an efficient myocardial imaging agent, while in humans it remains in the blood pool. The complex is 100% protein bound in animals and humans, but whereas in humans it is attached to a 51.5 kdalton protein (probably prealbumin), in rabbits it appears to be bound to a larger macromolecule (M.W.>100 kdalton). The efficiency of the complex for blood pool labelling was tested in a human volunteer and compared with the standard in vivo red cell labelling technique with stannous pyrophosphate. A satisfactory radionuclide angiogram could be performed with less than 370 MBq of the complex. The count rate for the complex (cps/MBq) was 15% higher than that obtained with the labelled red cells and the absence of splenic activity was ...

1987-04-01

256

The CBM potential of the Foothills/Mountain region of Alberta  

Energy Technology Data Exchange (ETDEWEB)

This presentation described the geology of the Kootenay, Gething, Gates, Brazeau and Coalspur Formations in the potential gas-bearing coal zones of the Alberta Foothills/Mountains. The future potential of this region for coalbed methane (CBM) exploitation was discussed, based on available data from drilling activity and the results of a recent coal desorption and adsorption study in the Val d'Or seam of the Coalspur formation. The gas content of the 5 coal zones was evaluated and compared with previous CBM exploration in the area. For evaluation purposes, the coal zones were divided into shallow and deep coal zones. The potential gas content of the shallow coal zones is approximately 31 Tcf of CBM. This is considered an inferred, initial, in-place, CBM resource estimate based on limited data. The gas content of deep zones is approximately 99 Tcf of in-place CBM gas. As such, the total ultimate CBM resource is estimated at 130 Tcf. Although these coal zones ...

2006-07-01

257

Regional evaluation of the Coalbed-Methane Potential of the Foothills/Mountains of Alberta. Revision 2  

Energy Technology Data Exchange (ETDEWEB)

This report describes the geology of the following 5 Alberta Foothills/Mountains coal zones: the Kootenay, Gething, Gates, Brazeau and Coalspur coal zones. The coal areas were assessed for gas content and compared with previous coalbed methane (CBM) exploration in the area. The coal zones can be divided into shallow (less than 1000 m depth) and deep (greater than 1000 m depth) coal zones for evaluation purposes. The potential gas content of the shallow coal zones is approximately 31 Tcf of CBM. This is considered an inferred, initial, in-place, CBM resource estimate based on limited data. The gas content of deep zones is approximately 99 Tcf of in-place CBM gas. Therefore, the total ultimate CBM resource is estimated at 130 Tcf. CBM recovery is not usually attempted due to high drilling costs and low permeability. The only CBM production from the Foothills has been from the southern Alberta Kootenay coal zone, and this was limited. The shallow ...

2002-10-01

258

Multidimensional B-spline parameterization of the detection probability of PET systems to improve the efficiency of Monte Carlo simulations  

International Nuclear Information System (INIS)

Accurate modeling of system response and scatter distribution is crucial for image reconstruction in emission tomography. Monte Carlo simulations are very well suited to calculate these quantities. However, Monte Carlo simulations are also slow and many simulated counts are needed to provide a sufficiently exact estimate of the detection probabilities. In order to overcome these problems, we propose to split the simulation into two parts, the detection system and the object to be imaged (the patient). A so-called 'virtual boundary' that separates these two parts is introduced. Within the patient, particles are simulated conventionally. Whenever a photon reaches the virtual boundary, its detection probability is calculated analytically by evaluating a multi-dimensional B-spline that depends on the photon position, direction and energy. The unknown B-spline knot values that define this B-spline are fixed by a prior 'pre-' simulation that needs to be run once for each scanner type. After ...

2010-06-21

259

Effects on fatigue life of gate valves due to higher torque switch settings during operability testing  

Energy Technology Data Exchange (ETDEWEB)

Some motor operated valves now have higher torque switch settings due to regulatory requirements to ensure valve operability with appropriate margins at design basis conditions. Verifying operability with these settings imposes higher stem loads during periodic inservice testing. These higher test loads increase stresses in the various valve internal parts which may in turn increase the fatigue usage factors. This increased fatigue is judged to be a concern primarily in the valve disks, seats, yokes, stems, and stem nuts. Although the motor operators may also have significantly increased loading, they are being evaluated by the manufacturers and are beyond the scope of this study. Two gate valves representative of both relatively weak and strong valves commonly used in commercial nuclear applications were selected for fatigue analyses. Detailed dimensional and test data were available for both valves from previous studies at the Idaho National Engineering ...

1995-12-01

260

Effect of chemical composition of SiO{sub x} films on rapid formation of Si nanocrystals induced by thermal plasma jet irradiation  

Energy Technology Data Exchange (ETDEWEB)

Si nanocrystal floating gate MOS capacitors were formed on p-Si (100) wafers by thermal plasma jet (TPJ) annealing of SiO{sub 2}/SiO{sub x} /SiO{sub 2}/Si(100) stacked structure. The chemical composition of SiO{sub x} layer was controlled by changing the SiH{sub 4}, He, and O{sub 2} gas flow ratio during plasma enhanced chemical vapour deposition. The MOS capacitors showed clear hysteresis in capacitance-voltage (CV) characteristics after TPJ annealing. The hysteresis width shows maximum value when initial composition x =1.7, which shows the maximum photoluminescence (PL) intensity. The maximum hysteresis width of 6.8 V was observed with gate voltage swept between 20 and -20 V in x = 1.7 sample. The result means 7.4 x 10{sup 12} cm{sup -2} carriers are injected to or emitted from Si nanocrystals. The duration of 1 V shift in flatband voltage was {proportional_to}0.1 ms with 20 V pulse, and charged carriers were stably maintained for ...

2010-04-15

261

Modeling, Simulation Design and Control of Hybrid-Electric Vehicle Drives  

Energy Technology Data Exchange (ETDEWEB)

Ohio State University (OSU) is uniquely poised to establish such a center, with interdisciplinary emphasis on modeling, simulation, design and control of hybrid-electric drives for a number of reasons, some of which are: (1) The OSU Center for Automotive Research (CAR) already provides an infrastructure for interdisciplinary automotive research and graduate education; the facilities available at OSU-CAR in the area of vehicle and powertrain research are among the best in the country. CAR facilities include 31,000 sq. feet of space, multiple chassis and engine dynamometers, an anechoic chamber, and a high bay area. (2) OSU has in excess of 10 graduate level courses related to automotive systems. A graduate level sequence has already been initiated with GM. In addition, an Automotive Systems Engineering (ASE) program cosponsored by the mechanical and electrical engineering programs, had been formulated earlier at OSU, independent of the GATE program proposal. The ...

2005-09-30

262

Two dimensional power spectral density measurements of X-rayoptics with the Micromap interferometric microscope  

Energy Technology Data Exchange (ETDEWEB)

A procedure and software have been developed to transform the area distribution of the residual surface heights available from the measurement with the Micromap interferometric microscope into a two-dimensional (2D) power spectral density (PSD) distribution of the surface height. The procedure incorporates correction of one of the spectral distortions of the PSD measurement. The distortion appears as a shape difference between the tangential and sagittal PSD spectra deduced from the 2D PSD distribution for an isotropic surface. A detailed investigation of the origin of the anisotropy was performed, and a mathematical model was developed and used to correct the distortion. The correction employs a modulation transfer function (MTF) of the detector deduced analytically based on an experimentally confirmed assumption about the origin of the anisotropy due to the asymmetry of the read-out process of the instrument's CCD camera. The correction function has only one free parameter, ...

2005-05-12

263

Study of the Photon Strength Functions for Gadolinium Isotopes with the DANCE Array  

Science.gov (United States)

The gadolinium isotopes are interesting for reactor applications as well as for medicine and astrophysics. The gadolinium isotopes have some of the largest neutron capture cross sections. As a consequence they are used in the control rod in reactor fuel assembly. From the basic science point of view, there are seven stable isotopes of gadolinium with varying degrees of deformation. Therefore they provide a good testing ground for the study of deformation dependent structure such as the scissors mode. Decay gamma rays following neutron capture on Gd isotopes are detected by the DANCE array, which is located at flight path 14 at the Lujan Neutron Scattering Center at Los Alamos National Laboratory. The high segmentation and close packing of the detector array enable gamma-ray multiplicity measurements. The calorimetric properties of the DANCE array coupled with the neutron time-of-flight technique enables one to gate on a specific resonance of a specific isotope in ...

2009-03-10

264

Simulation for transient stability study of the Taiwan power system - a nuclear majority system  

Energy Technology Data Exchange (ETDEWEB)

A transient stability program was developed for the Taiwan Power Company, which has a high proportion of nuclear generation in its power system. This program offers a new territory to investigate nuclear plant effects on the power system transient stability. This program also provides a high speed tool for the Taipower system operational planning. A generalized procedure of synchronous machine modeling for a large-scale stability study is presented. The merits and weaknesses of machine modeling can be comprehended through each item of this procedure. Three types of nonlinear synchronous machine modeling implemented into this stability program are derived by following this procedure. A robust subroutine was derived to perform the fourth order Runge-Kutta integration method, making the software programming neat and systematical. For simulating the nuclear plant influence on the system, this program implemented an additional four functions: load-limit operation simulated by a low-value ...

1984-01-01

265

Simulation for transient stability study of the Taiwan power system - a nuclear majority system  

International Nuclear Information System (INIS)

A transient stability program was developed for the Taiwan Power Company, which has a high proportion of nuclear generation in its power system. This program offers a new territory to investigate nuclear plant effects on the power system transient stability. This program also provides a high speed tool for the Taipower system operational planning. A generalized procedure of synchronous machine modeling for a large-scale stability study is presented. The merits and weaknesses of machine modeling can be comprehended through each item of this procedure. Three types of nonlinear synchronous machine modeling implemented into this stability program are derived by following this procedure. A robust subroutine was derived to perform the fourth order Runge-Kutta integration method, making the software programming neat and systematical. For simulating the nuclear plant influence on the system, this program implemented an additional four functions: load-limit operation simulated by a low-value ...

266

Rational protection of the quality of coastal waters by means of integrated, real-time management of the water environment; Proteccion racional de la calidad de las aguas costeras mediante la gestion integrada y en tiempo real del medio hidrico  

Energy Technology Data Exchange (ETDEWEB)

Before the implementation Water Framework directive, it was usual to forget that a good environment protection of the receiving waters needs a correct and coordinated operation of the subsystems of the water cycle, specially sewerage system, WWTP and receiving waters. This explains that most of the countries have focused their efforts in the treatment of dry weather flows forgetting the management of wet weather flows. Actually the idea that a sewerage system or a WWTP can not be planned or managed independently without considering the effects on the receiving waters is commonly accepted because not only each one of these systems must work correctly but also it is required a minimum impact in the receiving waters of the sewerage and WWTP overflows in dry and wet weather. All these links will affect the management strategy of the sewerage system (storm water detection tanks, gates, pumping stations, etc)., the interceptor, the WWTP and the receiving waters. Only an ...

2005-07-01

267

Preliminary results from an advanced lighting controlstestbed  

Energy Technology Data Exchange (ETDEWEB)

Preliminary results from a large-scale testbed of advanced lighting control technologies at the Phillip Burton Federal Building at 450 Golden Gate Ave. in San Francisco are presented. The first year objective of this project is to determine the sustainable energy savings and cost-effectiveness of different lighting control technologies compared to a portion of the building where only minimal controls are installed. The paper presents the analyzed results from six months of tests focused on accurately characterizing the energy savings potential of one type of daylight-linked lighting controls compared to the lighting in similar open-planned areas without dimming controls. After analyzing a half year;s data, we determined that the annual energy savings for this type of daylight- linked controls was 41% and 30% for the outer rows of lights on the South and North sides of the building, respectively. The annual energy savings dropped to 22% and 16% for the second row of ...

1998-03-01

268

Phosphorous adsorption and precipitation in a permeable reactive wall: Applications for wastewater disposal systems  

Energy Technology Data Exchange (ETDEWEB)

A permeable reactive mixture has been developed using low cost, readily available materials that is capable of providing effective, long-term phosphorous treatment in areas impacted by on-land wastewater disposal. The reactive mixture creates a geochemical environment suitable for P-attenuation by both adsorption and precipitation reactions. Potential benefits include significant reductions in phosphorous loading to receiving groundwater and surface water systems, and the accumulation of P-mass in a finite and accessible volume of material. The mixture may be applied as a component within surface treatment systems or in subsurface applications such as horizontal or vertical permeable reactive walls. The mixture averaged > 90% treatment efficiency over 3.6 years of continuous-flow laboratory column experiments. The mixture was further evaluated at the pilot-scale to treat municipal wastewater, and the field-scale to treat a well-characterized septic system plume using an in situ ...

1997-12-31

269

Numerical flow simulation in ship and ocean engineering; Senpaku kaiyo suiri bun`ta deno ryutai suchi simulation  

Energy Technology Data Exchange (ETDEWEB)

The improvement in the functions of the viscous flow calculation method VEGA-SHIP around a ship and the expansion of application range were described as the numerical flow simulation in ship and ocean engineering and at the same time application examples to the ocean engineering by the general-purpose flow simulation code FLOW-3D handling the non-steady flow with a free surface were introduced as the numerical simulation regarding such products as a water gate and a dam. In the VEGA-SHIP, water surface was handled as a fixed wall so that wave could not be calculated. Therefore, an algorithm for calculating wave on the water surface was added to the VEGA-SHIP and a calculation method simultaneously considering the creation of wave around the ship and viscosity was developed. The FLOW-3D was used to calculate the phenomenon where inside liquid moved greatly due to the oscillation of a tank and hit against and damaged the tank ceiling in the tank, etc. for storing ...

1995-01-01

270

Models of continuous-variable quantum computing  

Energy Technology Data Exchange (ETDEWEB)

We discuss strictly efficient models for measurement-based quantum computing using physical continuous variables, such as field modes of light. Such measurement-based quantum computing (MBQC) provides a promising paradigm for quantum computation as it does not require performing unitary gates during the computation, but rather appropriate readout. Here, we introduce novel schemes for which the resource state can be reasonably and efficiently prepared, and which notably do not require having infinite squeezing or mean energy available. What is more, error correction techniques are implementable, as the logical information is stored in finite-dimensional objects grasping correlations of the quantum states. Using the ideas of computational tensor networks we discuss how to sequentially prepare suitable physical resource states with cavity QED or with non-linear optics and how to efficiently implement a computational universal set of quantum operations with feasible ...

2009-07-01

271

Method of unilateral relaxation of a stressed rock mass intended to protect development workings  

Energy Technology Data Exchange (ETDEWEB)

Introduces three designs of development working protection recommended for immediate roof, basic roof and a coal seam of 1.5-2 m, 2.5-4 m and 0.7-1.1 m thickness respectively. The first design of roof control includes a dummy road with breaker props (cutting-off support) and pack, and reinforced concrete props. The second pattern comprises a breaking gate, two rows of cutting-off timber support, up to 10 m long pack and wood chocks. According to the third pattern a breaking road was executed 5.7-6 m away from the face end with breaker props at both its sides. Two rows of pack chocks were added to the dip. Advantages and drawbacks of the three patterns are pointed out. Stress distribution in rock is shown. Position of roof and support before and after roof settling is shown. The cost of the three methods is analyzed. Recommendations useful in application of the method are provided.

1991-06-01

272

MOS flat-band capacitance method at low temperatures  

Energy Technology Data Exchange (ETDEWEB)

The expression C/sub FB/ = C/sub ox/ x ({element of}/sub si//L/sub D/)/(C/sub ox/ + ({Epsilon}/sub si//L/sub D/)) (where L/sub D/ is the Debye length), commonly used for the flat-band capacitance of the MOS structure, is invalid in the temperature range below 100 {Kappa}. Consequently, significant error may be encountered when the flat-band capacitance method is used to extract the flat-band voltage V/sub FB/, which is of considerable interest for both the modeling and characterization of MOS devices. To extend this method to low-temperature CMOS applications one has to use a more general model that can be obtained by applying Fermi-Dirac statistics and taking into account the impurity freezeout effect. The authors show that when the temperature dependence of V/sub FB/ is extracted using this approach, the experimental data for n/sup +/ polysilicon gate MOS capacitors are in a good agreement with a simple model.

1989-08-01

273

Indirect heating of natural gas using vapor chambers; Aquecimento indireto de gas natural com uso de camaras de vapor  

Energy Technology Data Exchange (ETDEWEB)

Operation safety and reliability are major guidelines in the design of city-gate units. Conventional natural gas heaters operate by a indirect mechanism, where liquid water is used to transfer heat by natural convection between the combustion chamber and the natural gas coil. In this work, the concept of vapor chamber is evaluated as an indirect gas heater. In a vapor chamber, liquid water is in contact with the heat source, and vaporizes. The vapor condenses in contact with the heat sink. A reduced scale model was built and tested in order to compare these two heating concepts where the combustion chamber was replaced by electrical cartridge heaters. This engineering model can operate either as a conventional heater or as a vapor chamber. The comparison between the concepts was done by inducing a controlled power to the cartridges and by measuring the resulting temperature distributions. In the novel design, the heat exchanger efficiency increases, and the thermal ...

2005-07-01

274

High-performance thin-film transistors fabricated using excimer laser processing and grain engineering  

Energy Technology Data Exchange (ETDEWEB)

High-performance polysilicon thin-film transistors (TFT`s) are fabricated using an excimer laser to recrystallize the undoped channel and dope the source-drain regions. Using a technique the authors call grain engineering they are able to control grain microstructure using laser parameters. Resulting polysilicon films are obtained with average grain sizes of {approximately}4--9 {micro}m in sub-100 nm thick polysilicon films without substrate heating during the laser recrystallization process. Using a simple four-mask self-aligned aluminum top-gate structure, they fabricate TFT`s in these films. By combining the grain-engineered channel polysilicon regions with laser-doped source-drain regions, TFT`s are fabricated with electron mobilities up to 260 cm{sup 2}/Vs and on/off current ratios greater than 10{sup 7} To their knowledge, these devices represent the highest performance laser-processed TFT`s reported to date fabricated without substrate heating or ...

1998-04-01

275

High sensitivity detection and characterization of the chemical state of trace element contamination on silicon wafers  

CERN Document Server

Increasing the speed and complexity of semiconductor integrated circuits requires advanced processes that put extreme constraints on the level of metal contamination allowed on the surfaces of silicon wafers. Such contamination degrades the performance of the ultrathin SiO sub 2 gate dielectrics that form the heart of the individual transistors. Ultimately, reliability and yield are reduced to levels that must be improved before new processes can be put into production. It should be noted that much of this metal contamination occurs during the wet chemical etching and rinsing steps required for the manufacture of integrated circuits and industry is actively developing new processes that have already brought the metal contamination to levels beyond the measurement capabilities of conventional analytical techniques. The measurement of these extremely low contamination levels has required the use of synchrotron radiation total reflection X-ray fluorescence (SR-TXRF) ...

2003-01-01

276

Generalized simulation model for reservoir system analysis. Technical paper  

Energy Technology Data Exchange (ETDEWEB)

This paper overviews the general features of computer program 'HEC-5, Simulation of Flood Control and Conservation Systems', with emphasis on the capabilities of the most recent release of HEC-5, Version 7.2, dated March 1991. HEC-5 can simulate the essential features and operation goals and constraints of simple or complex systems with simulation intervals ranging from minutes to one month. Single event flood analysis and period of record conservation analysis may be accomplished with the model. Flood control analysis includes balanced system operation for downstream damage centers with consideration of forecasted local flows and hydrologic routing. In addition, induced surcharge operation based on spillway gate regulation schedules can be simulated. Hydropower analysis may include run-of-river, peaking, and pumped storage plants as well as system power operation. Water supply simulation can include reservoir and downstream flow requirements in ...

1992-03-01

277

Fast diagnosis and treatment of crack-like defect injuriousness in nuclear power plant equipment  

Energy Technology Data Exchange (ETDEWEB)

Increasingly stringent safety requirements governing the nuclear industry have made it essential to gain in-depth knowledge of the injuriousness of cracking phenomena in auxiliary and secondary nuclear power plant systems, and to devise methods of rapidly evaluating potentially injurious flaws. The Defect Injuriousness Diagnosis and Treatment Package (DIDTP) discussed in this paper was developed by Framatome, a French-based PWR builder, with this goal in mind. A general description is given of the DIDTP, which is made up of tables and nomographs illustrating the injuriousness of flaws liable to be encountered in the most severely loaded regions of plant systems. The basic principles underlying the DIDTP, together with computational methods and application procedure, are detailed. Two practical examples illustrating the use of the diagnostic system are presented, one applied to the main steam line, the other to gate valve wedges. The types of results obtained and ...

1985-01-01

278

Fabrication of single nanofluidic channels in poly(methylmethacrylate) films via focused-ion beam milling for use as molecular gates  

International Nuclear Information System (INIS)

Focused-ion beam (FIB) milling provides rapid fabrication of individual cylindrical submicrometer channels with reproducible dimensions (#+-#5% diameters) through 8-#mu#m thick poly(methylmethacrylate) (PMMA) films. PMMA films are spincast on sacrificial Si carriers and sputter-coated with Au before the 30-kV gallium FIB milling process. By adding a trace amount of poly(ethyleneoxide) and poly(dimethylsiloxane) to the PMMA solution before casting, the films can be released for subsequent mounting in microfluidic devices to create hybrid microfluidic-nanofluidic multilevel architectures. In situ FIB sectioning demonstrates the smooth cylindrical surface within the pore. Placing a milled film in contact with an aqueous fluorescein solution fills the channel by capillary action, as verified by confocal fluorescence microscopy. Confocal fluorescence of dyed films reveals that the pores span the thickness of the PMMA film. Small arrays of channels with a defined number and density and ...

2004-08-16

279

Fabrication and characterization of polyterpenol as an insulating layer and incorporated organic field effect transistor  

Energy Technology Data Exchange (ETDEWEB)

A non-synthetic polymer material, polyterpenol, was fabricated using a dry polymerization process namely RF plasma polymerization from an environmentally friendly monomer and its surface, optical and electrical properties investigated. Polyterpenol films were found to be transparent over the visible wavelength range, with a smooth surface with an average roughness of less than 0.4 nm and hardness of 0.4 GPa. The dielectric constant of 3.4 for polyterpenol was higher than that of the conventional polymer materials used in the organic electronic devices. The non-synthetic polymer material was then implemented as a surface modification of the gate insulator in field effect transistor (OFET) and the properties of the device were examined. In comparison to the similar device without the polymer insulating layer, the polyterpenol based OFET device showed significant improvements. The addition of the polyterpenol interlayer in the OFET shifted the threshold voltage ...

2010-08-31

280

Etching characteristics of high-k dielectric HfO2 thin films in inductively coupled fluorocarbon plasmas  

Science.gov (United States)

Inductively coupled fluorocarbon (CF4/Ar and C4F8/Ar) plasmas were used to etch HfO2, which is a promising high-dielectric-constant material for the gate of complementary metal-oxide-semiconductor devices. The etch rates of HfO2 in CF4/Ar plasmas exceeded those in C4F8/Ar plasmas. The tendency for etch rates to become higher in fluorine-rich (high F/C ratio) conditions indicates that HfO2 can be chemically etched by fluorine-containing species. In C4F8/Ar plasmas with a high Ar dilution ratio, the etch rate of HfO2 increased with increasing bias power. The etch rate of Si, however, decreasd with bias power, suggesting that the deposition of carbon-containing species increased with increasing the power and inhibited the etching of Si. The HfO2/Si selectivity monotonically increased with increasing power, then became more than 5 at the highest tested bias power. The carbon-containing species to inhibit etching of Si play an important role in enhancing the HfO2/Si ...

2005-11-01

281

Electrical characteristics of AlxGa1-xN Schottky diodes prepared by a two-step surface treatment  

Science.gov (United States)

Near-ideal Schottky barrier contacts to n-type Al0.22Ga0.78N have been developed by a two-step surface treatment technique. Plasma etching of the AlxGa1-xN surface prior to Schottky metal deposition, combined with sequential chemical treatment of the etched surface, holds promise for developing high quality low-leakage Schottky contacts for low noise applications and for recessed gate high electron mobility transistors. In this work, the effect of postetch chemical treatment of the n-type Al0.22Ga0.78N surface on the performance of the Ni/Au based Schottky contact has been investigated. Three different types of chemical treatment: viz, reactive ion etching, reactive ion etching plus dipping in hot aqua regia, and reactive ion etching plus dipping in hot KOH, are studied. Detailed current-voltage studies of three different surface treated diodes and a comparison with as-deposited diodes reveal significant improvement in the diode characteristics. The latter surface ...

2004-09-01

282

ETHERNET BASED EMBEDDED SYSTEM FOR FEL DIAGNOSTICS AND CONTROLS  

Energy Technology Data Exchange (ETDEWEB)

An Ethernet based embedded system has been developed to upgrade the Beam Viewer and Beam Position Monitor (BPM) systems within the free-electron laser (FEL) project at Jefferson Lab. The embedded microcontroller was mounted on the front-end I/O cards with software packages such as Experimental Physics and Industrial Control System (EPICS) and Real Time Executive for Multiprocessor System (RTEMS) running as an Input/Output Controller (IOC). By cross compiling with the EPICS, the RTEMS kernel, IOC device supports, and databases all of these can be downloaded into the microcontroller. The first version of the BPM electronics based on the embedded controller was built and is currently running in our FEL system. The new version of BPM that will use a Single Board IOC (SBIOC), which integrates with an Field Programming Gate Array (FPGA) and a ColdFire embedded microcontroller, is presently under development. The new system has the features of a low cost IOC, an open ...

2006-10-24

283

Applications of cathodic protection for the protection of aqueous and soil corrosion of power plant components  

International Nuclear Information System (INIS)

Power plant components exposed to environments such as water and soil are susceptible to severe corrosion. Many times the effect of corrosion in power plant components can be catastrophic. The problem is aggravated for underground pipelines due to additional factors such as large network of pipelines, proximity to earth mat, high voltage transmission lines, corrosive chemicals, inadequate approach etc. Other components such as condenser water boxes, internals of pipelines, clarifier bridge structures, cooling water inlet gates and pipes etc. which are in continuous contact with water, are subjected to severe corrosion. The nature and locations of all such components are at places which are not accessible for routine maintenance and hence they require long term reliable protection against corrosion. Experience has shown that anti-corrosive coatings are inadequate in preventing corrosion and due to their location regular maintenance coatings are also not feasible. ...

1999-11-22

284

An aerial radiological survey of the Oak Ridge Reservation, Oak Ridge, Tennessee  

International Nuclear Information System (INIS)

An aerial radiological survey of the Oak Ridge Reservation (ORR) and surrounding area in Oak Ridge, Tennessee, was conducted during the period March 30 to April 14,1992. The purpose of the survey was to measure and document the terrestrial radiological environment of the Oak Ridge Reservation for use in environmental management programs and emergency response planning. The aerial survey was flown at an altitude of 150 feet (46 meters) along a series of parallel lines 250 feet (76 meters) apart and included X-10 (Oak Ridge National Laboratory), K-25 (former Gaseous Diffusion Plant), Y-12 (Weapons Production Plant), the Freels Bend Area and Oak Ridge Institute for Science and Education, the East Fork Poplar Creek (100-year floodplain extending from K-25 to Y-12), Elza Gate (former uranium ore storage site located in the city of Oak Ridge), Parcel A, the Clinch River (river banks extending from Melton Hill Dam to the city of Kingston), and the CSX Railroad Tracks ...

1993-06-22

285

An accurate high-speed single-electron quantum dot pump  

International Nuclear Information System (INIS)

Using standard microfabrication techniques, it is now possible to construct devices that appear to reliably manipulate electrons one at a time. These devices have potential use as building blocks in quantum computing devices, or as a standard of electrical current derived only from a frequency and the fundamental charge. To date, the error rate in semiconductor 'tuneable-barrier' pump devices, those which show most promise for high-frequency operation, have not been tested in detail. We present high-accuracy measurements of the current from an etched GaAs quantum dot pump, operated at zero source-drain bias voltage with a single ac-modulated gate at 340 MHz driving the pump cycle. By comparison with a reference current derived from primary standards, we show that the electron transfer accuracy is better than 15 parts per million. High-resolution studies of the dependence of the pump current on the quantum dot tuning parameters also reveal possible deviations from a ...

2010-07-01

286

[New cardiotonic agents].  

Science.gov (United States)

The possibilities for therapy in the field of severe cardiac insufficiency have been extended in recent years by the introduction of novel agents endowed with a positive inotropic action. These substances may be arranged in two large classes: sympathomimetic agents and "non sympathomimetic--non digitalis-like" inotropic agents. The stimulant action of noradrenaline, adrenaline and isoproterenol on beta-adrenergic myocardial receptors has been clearly demonstrated but the usefulness of these medicines is limited by their positive chronotropic and arrhythmogenic actions. Dopamine and dobutamine have proved to be very useful in the treatment of patients in intensive care units. However, the exclusively intravenous route of administration limits their importance to the medium or long term. Several compounds, which are active by the oral route, have been the subject of therapeutic trials for the short or medium term. The problems posed by their use result, in the first ...

1985-12-01

287

The influence of melatonin on metabolic changes in female rats induced by continuous irradiation and/or administration of 7,12-dimethylbenz/a/anthracene  

International Nuclear Information System (INIS)

Metabolic profile is an important biological marker of neoplastic processes not only in the tumor itself but also in the host organism. The neuro-hormone melatonin has been implicated in the experiments as an oncostatic agent. Female Wistar:Han SPF rats (Velaz, Prague, Czech Republic) were irradiated continuously for 15 days using a daily gamma rays dose of 96 mGy. At the end of exposure one group of rats was administered 5 mg/kg b.w. of dimethylbenz/a/anthracene (DMBA) intragastrically. During the period of exposure to ionizing radiation a part of the animals was supplied with melatonin (M) at a concentration of 20 #mu#l/ml in drinking water. Selected parameters of lipid and carbohydrate metabolism and levels of selected hormones were determined 2, 30 and 100 days post-irradiation. The irradiation itself caused only small changes in tissue lipids. The application of a single low dose (subthreshold from the point of view of induction of mammary tumors) of DMBA caused more pronounced ...

288

Radiolabelled D2 agonists as prolactinoma imaging agents  

Energy Technology Data Exchange (ETDEWEB)

During the past year, further studies on mAChR were conducted. These studies included verification of the difference in pituitary distribution based on ligand charge. The pituitary localization of TRB. A neutral mAChR ligand, was verified. The lack of QNB blockade of TRB uptake was tested by blockage with scopolamine, another mAChR antagonist and by testing the effect in a different strain of rat. Neither scopolamine or change of rat strain had any effect. We concluded that TRB uptake in pituitary is not a receptor-mediated process. Further studies were conducted with an additional quaternized mAChR ligand: MQNB. Pituitary localization of MQNB, like MTRB, could be blocked by pretreatment with QNB. We have tentatively concluded that permanent charge on a mAChR antagonist changes the mechanism of uptake in the pituitary. Time course studies and the effects of DES on myocardial uptake are reported. A brief report on preliminary results of evaluation of quaternized ...

1989-08-01

289

Pathogenesis of trypanosome infections in cattle  

International Nuclear Information System (INIS)

The potential application of radioisotopes are not discussed in this review of trypanosome pathogenesis in cattle. Initially, structural changes in the lymphoid system are characterized by marked proliferation and germinal centre formation, whereas in long-standing infections the lymphoid organs become depleted. These changes appear associated with immunodepression. Anaemia dominates the clinical disease syndrome in bovine trypanosomiasis. It develops with the onset of parasitaemia and is largely haemolytic, resulting from increased red blood cell destruction by phagocytosis. Several factors may be involved in this process including haemolysins produced by the trypanosome, immunological mechanisms, fever, disseminated intravascular coagulation and an expanded and active mononuclear phagocytic system. During this phase of the disease, cattle respond well to chemotherapy. However, in later phases of the disease, when trypanosomes cannot be detected, the anaemia sometimes persists and ...

1979-05-11

290

Kinetics of in vivo binding of antagonist to muscarinic cholinergic receptor in the human heart studied by Positron Emission Tomography  

Energy Technology Data Exchange (ETDEWEB)

Positron Emission Tomography (PET) was used to analyze in vivo antagonist binding to human myocardial muscarinic cholinergic receptor. The methiodide salt of the muscarinic antagonist, quinuclidinyl benzilate (MQNB), was labeled with the positron emitter, Carbon-11, and injected intravenously to 8 normal subjects. /sup 11/C-MQNB concentration was determined in vivo in the ventricular septum from 40 cross-sectional images acquired at the same transverse level over a period of 70 minutes. In 4 subjects, various amounts of unlabeled atropine were rapidly injected at 20 minutes to study whether atropine competitively inhibited MQNB. The kinetics of binding of /sup 11/C-MQNB were not the same in vivo and in vitro. The apparent dissociation rate of /sup 11/C-MQNB in vivo was much slower (by 1 to 2 orders of magnitude) than that observed in vitro with /sup 3/H-QNB. After atropine injection, /sup 11/C-MQNB dissociated from its binding sites at a rate that apparently ...

1984-08-27

291

Effects of exogenous norepinephrine on the spatial distribution of cardiac MIBG accumulation. Comparison with myocardial blood flow  

International Nuclear Information System (INIS)

Male rats were injected intravenously for 15 min with physiological saline (as control) (0.05 #mu#g/kg/min) or norepinephrine (NE) (0.1 #mu#g/kg/min) followed by 740 kBq of MIBG. Rats were injected for more 30 min (early stage group) and for more 4 hr (late stage group) with physiological saline or NE. Five MBq of "9"9"mTc-tetrofosmin (TF) was administered instead of MIBG in another group. The heart was isolated and uptake of MIBG or TF of right ventricle, apex, and left ventricle (divided into 8 parts) was measured. In control group, MIBG uptake of apex was significantly lower than that of lateral wall in both early and late groups. In NE group, MIBG uptake showed a tendency to decrease in both early and late groups. Compared with control group, the uptake of anterior wall in late group decreased significantly at NE 0.1 #mu#/kg/min. The TF uptake in control group was not different in each part. In NE group, the TF uptake of right ventricle decreased significantly compared with that of ...

1998-06-01

292

Effects of chronic swimming training on cardiac sarcolemmal function and composition.  

Science.gov (United States)

Cardiac contractile function is dependent on the integrity and function of the sarcolemmal membrane. Swimming exercise training is known to increase cardiac contractile performance. The purpose of the present study was to examine whether a swimming exercise program would alter sarcolemmal enzyme activity, ion flux, and composition in rat hearts. After approximately 11 wk of exercise training, cardiac myosin and actomyosin Ca2+-adenosinetriphosphatase (ATPase) activity was significantly higher in exercised rat hearts than in sedentary control rat hearts. Glycogen content was increased in plantaris and gastrocnemius muscles from exercised animals as was succinic dehydrogenase activity in gastrocnemius muscle of exercised rats in comparison to sedentary rat preparations. Sarcolemmal vesicles were isolated from hearts of exercise-trained and control rats. Sarcolemmal Na+-K+-ATPase and K+-p-nitrophenylphosphatase activities, Na+-Ca2+ exchange, and passive Ca2+ binding did not differ between ...

1989-04-01

293

Characterization of tris(N-substituted-2-methyl-3-hydroxy-4-pyridinonato)technetium(IV) cations  

Energy Technology Data Exchange (ETDEWEB)

A burgeoning interest in technetium coordination chemistry has been spurred by its widespread use in nuclear medicine. Recent focus has been on the design and preparation of new technetium complexes, the lipophilicity, polarity, and overall charge of which can be readily altered by simple substitutions in the molecular framework of the ligand in order to optimize the biodistribution and target specific organs. Examples are cationic (Cardiolite) and neutral (Ceretec) technetium complexes, used as myocardial and brain imaging agents, respectively. The authors have been pursuing a continuing study of tris(3-hydroxy-4-pyridinonato)gallium and -indium complexes that are water soluble, are hydrolytically stable, and are of varying lipophilicity and neutral charge. Studies of in vivo in rabbits and mice have revealed that several of these cationic complexes may be useful as morphologic kidney imaging agents, with [{sup 99m}Tc(pap){sub 3}]{sup +} showing elevated levels in ...

1994-11-23

294

Characterization of tris(N-substituted-2-methyl-3-hydroxy-4-pyridinonato)technetium(IV) cations  

International Nuclear Information System (INIS)

A burgeoning interest in technetium coordination chemistry has been spurred by its widespread use in nuclear medicine. Recent focus has been on the design and preparation of new technetium complexes, the lipophilicity, polarity, and overall charge of which can be readily altered by simple substitutions in the molecular framework of the ligand in order to optimize the biodistribution and target specific organs. Examples are cationic (Cardiolite) and neutral (Ceretec) technetium complexes, used as myocardial and brain imaging agents, respectively. The authors have been pursuing a continuing study of tris(3-hydroxy-4-pyridinonato)gallium and -indium complexes that are water soluble, are hydrolytically stable, and are of varying lipophilicity and neutral charge. Studies of in vivo in rabbits and mice have revealed that several of these cationic complexes may be useful as morphologic kidney imaging agents, with ["9"9"mTc(pap)_3]"+ showing elevated levels in the kidneys ...

295

MRI-based N-staging in esophageal cancer; N-Staging des Oesophaguskarzinoms mittels MRT unter Verwendung von artefaktreduzierenden LOTA-Sequenzen  

Energy Technology Data Exchange (ETDEWEB)

Purpose: For planning the therapeutic strategies and estimating the prognosis in esophageal cancer, N-staging is very important. To date, MRI still is of minor importance as imaging modality of the mediastinum despite promising developments in the past, like ECG-gating or 'averaging' sequences, e.g. LOTA (Long-term averaging), which facilitate mediastinal and thoracic MR-imaging. In a prospective approach, the value of MRI based N-staging was examined with respect to LOTA-sequences. Material and Methods: Within from weeks prior to esophagectomy, standardized MRI of the esophagus was performed in 15 patients (10 squamous-cell-carcinomas and 5 adenocarcinomas) using a 1.5 T whole body scanner. Imaging quality was classified based on depiction of aortic wall or tracheal wall layers. Criteria for malignant infiltration were a diameter of more than 15 mm or a round appearance of a lymph node together with GD-DTPA enhancement. All data were blinded and ...

2002-10-01

296

Role of nuclear medicine and magnetic resonance imaging in cardiac diagnostics; Rolle der nuklearmedizinischen Verfahren und der Magnetresonanztomographie in der kardialen Diagnostik  

Energy Technology Data Exchange (ETDEWEB)

Nuclear medicine and magnetic resonance imaging (MRI) are widely used in cardiac diagnostics. Both techniques have been carefully evaluated and are equivalent for the assessment of regional and global wall motion as well as the evaluation of ejection fraction and cardiac volumes, though MRI is herein currently seen as gold standard. For evaluation of myocardial perfusion, extensive data exist for nuclear imaging, that, next to high diagnostic accuracy for evaluation of coronary artery disease, show incremental prognostic information and allow for independent risk stratification. Because of rapid technical advance, myocardial perfusion imaging has also become feasible with cardiac MRI. Results of recent studies are promising, but the data are few compared to perfusion scintigraphy. For viability assessment in patients with ischemic cardiomyopathy, positron emission tomography (PET) with FDG is currently seen as gold standard. However, single ...

2003-12-01

297

Waste reduction by separation of contaminated soils during environmental restoration  

Energy Technology Data Exchange (ETDEWEB)

During cleanup of contaminated sites, Sandia National Laboratories, New Mexico (SNL/NM) frequently encounters soils with low-level radioactive contamination. The contamination is not uniformly distributed, but occurs within areas of clean soil. Because it is difficult to characterize heterogeneously contaminated soils in detail and to excavate such soils precisely using heavy equipment, it is common for large quantities of uncontaminated soil to be removed during excavation of contaminated sites. This practice results in the commingling and disposal of clean and contaminated material as low-level waste (LLW), or possibly low-level mixed waste (LLMW). Until recently, volume reduction of radioactively contaminated soil depended on manual screening and analysis of samples, which is a costly and impractical approach and does not uphold As Low As Reasonably Achievable (ALARA) principles. To reduce the amount of LLW and LLMW generated during the excavation process, SNL/NM is evaluating two ...

1998-06-01

298

Special phased array applications for pipeline girth weld inspections  

Energy Technology Data Exchange (ETDEWEB)

Pipeline automated ultrasonic testing (AUT) uses fully automated equipment that travels around a pipe on a welding band in a linear scan to allow array pulses to provide ultrasound information on weld zones. Pipeline AUT is also used for zone discrimination as well as with special calibration blocks, dual gate output displays, and rapid defect sizing. AUT allows for the inspection of welds soon after completion, and can save construction costs by process control when combined with engineering critical assessment (ECA) to minimize rejection rates. Ultrasonic phased arrays (UPA) use an array of elements that are all individually wired, pulsed, and time-shifted. Elements are pulsed in groups of approximately 16 elements at a time for pipeline welds. Phased arrays can be used to combine electronic scanning, sectorial scanning and precision focusing to give a practical combination of displays. Optimum angles can be selected for welds and other components, and the ...

2004-07-01

299

Small-molecule screen identifies inhibitors of a human intestinal calcium-activated chloride channel.  

Science.gov (United States)

Calcium-activated chloride channels (CaCCs) are widely expressed in mammalian tissues, including intestinal epithelia, where they facilitate fluid secretion. Potent, selective CaCC inhibitors have not been available. We established a high-throughput screen for identification of inhibitors of a human intestinal CaCC based on inhibition of ATP/carbachol-stimulated iodide influx in HT-29 cells after lentiviral infection with the yellow fluorescent halide-sensing protein YFP-H148Q/I152L. Screening of 50,000 diverse, drug-like compounds yielded six classes of putative CaCC inhibitors, two of which, 3-acyl-2-aminothiophenes and 5-aryl-2-aminothiazoles, inhibited by >95% iodide influx in HT-29 cells in response to multiple calcium-elevating agonists, including thapsigargin, without inhibition of calcium elevation, calcium-calmodulin kinase II activation, or cystic fibrosis transmembrane conductance regulator chloride channels. These compounds also inhibited calcium-dependent chloride ...

2007-12-14

300

Resistance to powdery mildew in Spanish barley landraces is controlled by different sets of quantitative trait loci.  

Science.gov (United States)

Twenty-two landrace-derived inbred lines from the Spanish Barley Core Collection (SBCC) were found to display high levels of resistance to a panel of 27 isolates of the fungus Blumeria graminis that exhibit a wide variety of virulences. Among these lines, SBCC145 showed high overall resistance and a distinctive spectrum of resistance compared with the other lines. Against this background, the main goal of the present work was to investigate the genetic basis underlying such resistance using a doubled haploid population derived from a cross between SBCC145 and the elite spring cultivar Beatrix. The population was genotyped with the 1,536-SNP Illumina GoldenGate Oligonucleotide Pool Assay (Barley OPA-1 or BOPA1 for short), whereas phenotypic analysis was performed using two B. graminis isolates. A major quantitative trait locus (QTL) for resistance to both isolates was identified on the long arm of chromosome 6H (6HL) and accounted for ca. 60% of the phenotypic ...

2011-07-08

301

Quantitative imaging of turbulent and reacting flows  

Energy Technology Data Exchange (ETDEWEB)

Quantitative digital imaging, using planar laser light scattering techniques is being developed for the analysis of turbulent and reacting flows. Quantitative image data, implying both a direct relation to flowfield variables as well as sufficient signal and spatial dynamic range, can be readily processed to yield two-dimensional distributions of flowfield scalars and in turn two-dimensional images of gradients and turbulence scales. Much of the development of imaging techniques to date has concentrated on understanding the requisite molecular spectroscopy and collision dynamics to be able to determine how flowfield variable information is encoded into the measured signal. From this standpoint the image is seen as a collection of single point measurements. The present effort aims at realizing necessary improvements in signal and spatial dynamic range, signal-to-noise ratio and spatial resolution in the imaging system as well as developing excitation/detection strategies which provide ...

1993-12-01

302

MRI-based N-staging in esophageal cancer  

International Nuclear Information System (INIS)

Purpose: For planning the therapeutic strategies and estimating the prognosis in esophageal cancer, N-staging is very important. To date, MRI still is of minor importance as imaging modality of the mediastinum despite promising developments in the past, like ECG-gating or 'averaging' sequences, e.g. LOTA (Long-term averaging), which facilitate mediastinal and thoracic MR-imaging. In a prospective approach, the value of MRI based N-staging was examined with respect to LOTA-sequences. Material and Methods: Within from weeks prior to esophagectomy, standardized MRI of the esophagus was performed in 15 patients (10 squamous-cell-carcinomas and 5 adenocarcinomas) using a 1.5 T whole body scanner. Imaging quality was classified based on depiction of aortic wall or tracheal wall layers. Criteria for malignant infiltration were a diameter of more than 15 mm or a round appearance of a lymph node together with GD-DTPA enhancement. All data were blinded and separately read by ...

2002-10-01

303

HT technology -- All-metal sealing answers safety and environmental concerns  

Energy Technology Data Exchange (ETDEWEB)

This paper discusses the evolution of the horizontal subsea tree and its utilization in increasingly demanding applications. Initially, the Horizontal Tree was seen as a solution for wells requiring high well maintenance, such as those using electrical downhole pumps. Today, the horizontal tree is being applied to natural drive wells because of attractive whole life economics. This raises concern in a number of areas. Tubing hanger seals are permanently exposed to well fluids, and must provide high integrity sealing. This required the development of a new type of radially energized, all metal sealing system, specifically for horizontal tree applications, suitable for oil or gas service at working pressures to 15,000 psi. In addition, horizontal tree pressure integrity depends on the master valve stem, gate and bonnet seals. The need for high seal integrity also dictates that the first master valves should be integral to the main body of the tree, to maximize ...

1995-12-31

304

Fracture characterizatioin of the Bandelier tuff in OU-1098 (TA-2 and TA-41)  

Energy Technology Data Exchange (ETDEWEB)

Rock fracture characterization documents a total of 1496 fractures in unit 2 of the Tshirege Member of the Bandelier Tuff along 6013 feet of Los Alamos Canyon`s north wall adjacent to Operational Unit 1098. Geologically termed joints, these fractures likely owe their primary origin to brittle failure during the cooling contraction of the tuff after its emplacement nearly 1 million years ago. Subsequent tectonic movement along the Pajarito Fault system has modified fracture strikes, dips, apertures, and linear density. From a background linear density of approximately 20 fractures per 100-foot interval along the canyon wall, fracture density increases to values in excess of 50 fractures per 100-foot interval in a zone at and immediately east of the Omega West reactor building TA-2-1. This increase in fracture density is coincident with the mapped trace of the Guaje Mountain Fault (GMFZ) that apparently bifurcates with a branch running through the canyon at Building TA-2-1 and another ...

1996-10-01

305

Determination of radon-222 concentration in inside environments of the Instituto de Engenharia Nuclear, Brazil; Determinacao da concentracao de radonio-222 nos ambientes internos das instalacoes do Instituto de Engenharia Nuclear  

Energy Technology Data Exchange (ETDEWEB)

The gotten concentrations of radon-222 in the installations of the IEN had been determined using the active and passive methods. The active method consisted on the use of the alpha spectrometry with a portable equipment Tracerlab Instruments WLM- Plus. In the determination for the passive method, one used detectors of nuclear strokes of type LEXAN. The raised values had been gotten in the wastes deposit and its annexes, room of the press and laboratory of wastes handling. It was observed, in this sector, an instantaneous measure of alpha spectrometry, concentrations around 1000 Bq.m-3, which had over all to the function of storage, the sector, a great volume of natural radioactive materials, especially of radium-226. This determination was carried through in an extreme situation of ventilation zero, where the gates had been kept closed during the execution of the same one. It was observed, however, a considerable fall, with values ten times inferior, after to ...

2000-07-01

306

Dependence of mobility on shallow localized gap states in single-crystal organic field-effect-transistors  

Energy Technology Data Exchange (ETDEWEB)

In order to optimize the performance of molecular organic electronic devices it is important to study the intermolecular density of states and charge transport mechanisms in the environment of crystalline organic material. Using this approach in Field Effect Transistors (FETs) we show that material purification improves carrier mobility and decreases density of the deep localized electronic state. We also report a general exponential energy dependence of the density of localized states in a vicinity of the mobility edge (Fermi energies up to approx7 times higher than the thermal energy (kT)) in a variety of the extensively purified molecular organic crystal FETs. This observation and the low activation energy of the order of approxkT suggest that molecular structural misplacements of the sizes that are comparable with thermal molecular modes rather than impurity deep traps play a role in formation of these shallow states. We find that the charge carrier mobility in the FET ...

2009-12-15

307

Coal deposits in the front ranges and foothills of the Canadian Rocky Mountains, southern Canadian Cordillera  

Energy Technology Data Exchange (ETDEWEB)

Over one-third of Canada's coal resources occurs in the southern Canadian Rocky Mountains, with major deposits in the Front Ranges, Inner Foothills and Outer Foothills. In the Front Ranges, deposits of metallurgical and thermal, high-volatile bituminous to semi-anthracite coal occur in the Late Jurassic-Early Cretaceous Mist Mountain Formation. In the Inner Foothills of northeastern British Columbia and west-central Alberta, resources of metallurgical and thermal medium- and low-volatile bituminous coal occur in Early Cretaceous strata of the Gething and Gates Formations. In the Outer Foothills resources of thermal, high-volatile bituminous coal occur in Late Cretaceous and Paleocene strata of the Belly River Coalspur and Paskapoo Formations. The major deposits of the Front Ranges and Inner Foothills accumulated within the coastal plains of the Fernie and Moosebar-Clearwater seas. Shorelines prograded to the north and northeast into a foreland basin that ...

1993-09-01

308

Brain mechanisms supporting the modulation of pain by mindfulness meditation.  

Science.gov (United States)

The subjective experience of one's environment is constructed by interactions among sensory, cognitive, and affective processes. For centuries, meditation has been thought to influence such processes by enabling a nonevaluative representation of sensory events. To better understand how meditation influences the sensory experience, we used arterial spin labeling functional magnetic resonance imaging to assess the neural mechanisms by which mindfulness meditation influences pain in healthy human participants. After 4 d of mindfulness meditation training, meditating in the presence of noxious stimulation significantly reduced pain unpleasantness by 57% and pain intensity ratings by 40% when compared to rest. A two-factor repeated-measures ANOVA was used to identify interactions between meditation and pain-related brain activation. Meditation reduced pain-related activation of the contralateral primary somatosensory cortex. Multiple regression analysis was used to identify brain regions ...

2011-04-01

309

Basic study of entire whole-body PET scanners based on the OpenPET geometry  

International Nuclear Information System (INIS)

A conventional PET scanner has a 15-25 cm axial field-of-view (FOV) and images a whole body using about six bed positions. An OpenPET geometry can extend the axial FOV with a limited number of detectors. The entire whole-body PET scanner must be able to process a large amount of data effectively. In this work, we study feasibility of the fully 3D entire whole-body PET scanner using the GATE simulation. The OpenPET has 12 block detector rings with the ring diameter of 840 mm and each block detector ring consists of 48 depth-of-interaction (DOI) detectors. The OpenPET has the axial length of 895.95 mm with five parts of 58.95 mm open gaps. The OpenPET has higher single data loss than a conventional PET scanner at grouping circuits. NECR of the OpenPET decreases by single data loss. But single data loss is mitigated by separating the axially arranged detector into two parts. Also, multiple coincidences are found to be important for the entire whole-body PET scanner. ...

2010-09-01

310

A Virtual Engineering Framework for Simulating Advanced Power System  

Energy Technology Data Exchange (ETDEWEB)

In this report is described the work effort performed to provide NETL with VE-Suite based Virtual Engineering software and enhanced equipment models to support NETL's Advanced Process Engineering Co-simulation (APECS) framework for advanced power generation systems. Enhancements to the software framework facilitated an important link between APECS and the virtual engineering capabilities provided by VE-Suite (e.g., equipment and process visualization, information assimilation). Model enhancements focused on improving predictions for the performance of entrained flow coal gasifiers and important auxiliary equipment (e.g., Air Separation Units) used in coal gasification systems. In addition, a Reduced Order Model generation tool and software to provide a coupling between APECS/AspenPlus and the GE GateCycle simulation system were developed. CAPE-Open model interfaces were employed where needed. The improved simulation capability is demonstrated on selected ...

2008-06-18

311

Quantum information processing in nanostructures[Quantum optics; Quantum computing  

Energy Technology Data Exchange (ETDEWEB)

Since information has been regarded os a physical entity, the field of quantum information theory has blossomed. This brings novel applications, such as quantum computation. This field has attracted the attention of numerous researchers with backgrounds ranging from computer science, mathematics and engineering, to the physical sciences. Thus, we now have an interdisciplinary field where great efforts are being made in order to build devices that should allow for the processing of information at a quantum level, and also in the understanding of the complex structure of some physical processes at a more basic level. This thesis is devoted to the theoretical study of structures at the nanometer-scale, 'nanostructures', through physical processes that mainly involve the solid-state and quantum optics, in order to propose reliable schemes for the processing of quantum information. Initially, the main results of quantum information theory and quantum computation are ...

2002-07-01

312

Hood River Fish Habitat Project; Confederated Tribes of the Warm Springs Reservation of Oregon, Annual Report 2001-2002.  

Energy Technology Data Exchange (ETDEWEB)

This report summarizes the project implementation and monitoring of all habitat activities that occurred over Fiscal Year 2002 (FY 02). Some of the objectives in the corresponding statement of work for this contract were not completed within FY 02. A description of the progress during FY 02 and reasoning for deviation from the original tasks and timeline are given. OBJECTIVE 1--Provide coordination of all activities, administrative oversight and assist in project implementation and monitoring activities. Administration oversight and coordination of the habitat statement of work, budget, subcontracts and personnel was provided. OBJECTIVE 2--Develop, coordinate, and implement the Hood River Fish Habitat Protection, Restoration, and Monitoring Plan. The Hood River Fish Habitat Protection, Restoration, and Monitoring Plan was completed in 2000 (Coccoli et al., 2000). This document is utilized for many purposes including: drafting the Watershed Action Plan, ranking projects for funding, and ...

2003-11-01

313

Evaluation of left ventricular volumes in patients with congenital heart disease and abnormal left ventricular geometry. Comparison of MRI and transthoraic 3-dimensional echocardiography; Vergleich der transthorakalen 3D-Echokardiographie mit der MRT zur Bestimmung linksventrikulaerer Volumina bei Patienten mit pathologischer Ventrikelgeometrie aufgrund angeborener Herzfehler  

Energy Technology Data Exchange (ETDEWEB)

Purpose: To assess the new method of 3-dimensional echocardiography in comparison to the 'gold standard' MRI as to its ability to calculate left ventricular volumes in patients with congenital heart disease. Materials and methods: Eighteen patients between the ages of 3.9 to 37.3 years (mean: 12.8{+-}9.7) with a geometrically abnormal left ventricle were examined using a 1.5 T scanner with a fast gradient-echo sequence (TR=14 ms, TE=2.6-2.9 ms, FOV=300-400 mm, flip angle=20 , matrix=128:256, slice thickness=5 mm, retrospective gating) in multislice-multiphase technique. Transthoracic 3D-echocardiography was performed with a 3.5 MHz transducer and a Tomtec {sup trademark} (Munich, Germany) system for 3D reconstruction. Results: Volume calculation was possible in all patients with 3D-echocardiography, but the muscle mass calculation only succeeded in 11 to 18 patients (61%) due to inadequate visualization of the entire myocardium. Comparing MRI and ...

2003-07-01

314

What is the best contrast injection protocol for 64-row multi-detector cardiac computed tomography?  

International Nuclear Information System (INIS)

Objective: To determine the optimal contrast injection protocol for 64-MDCT coronary angiography. Materials and methods: One hundred and fifty consecutive patients scheduled to undergo retrospectively electrocardiographically gated 64-MDCT. Each 30 patients were assigned to use a different contrast protocol: group 1: uniphasic protocol (contrast injection without saline flush); group 2: biphasic protocol (contrast injection with saline flush); group 3A, 3B and 3C: triphasic protocol (contrast media + different saline diluted contrast media + saline flush). Image quality scores and artifacts were compared and evaluated on both transaxial and three-dimensional coronary artery images among each contrast protocol. Results: Among the triphasic protocol groups, group 3A (30%:70% contrast media-saline mixture was used in second phase) used the least contrast media and had the least frequency of streak artifacts, but there were no significant differences in coronary artery ...

2010-08-01

315

Target Diagnostic Instrument-Based Controls Framework for the National Ignition Facility  

Energy Technology Data Exchange (ETDEWEB)

NIF target diagnostics are being developed to observe and measure the extreme physics of targets irradiated by the 192-beam laser. The response time of target materials can be on the order of 100ps--the time it takes light to travel 3 cm--temperatures more than 100 times hotter than the surface of the sun, and pressures that exceed 109 atmospheres. Optical and x-ray diagnostics were developed and fielded to observe and record the results of the first 4-beam experiments at NIF. Hard and soft x-ray spectra were measured, and time-integrated and gated x-ray images of hydrodynamics experiments were recorded. Optical diagnostics recorded backscatter from the target, and VISAR laser velocimetry measurements were taken of laser-shocked target surfaces. Additional diagnostics are being developed and commissioned to observe and diagnose ignition implosions, including various neutron and activation diagnostics. NIF's diagnostics are being developed at LLNL and with ...

2007-05-07

316

Symmetries in nuclei near the centre of the f{sub 7/2} shell  

Energy Technology Data Exchange (ETDEWEB)

High-spin states in the mirror pair nuclei {sup 49}Cr and {sup 49}Mn and their cross-conjugate partners, the mirror pair {sup 47}V and {sup 47}Cr have been investigated using experimental {gamma}-ray spectroscopic techniques. The combination of high-efficiency EUROBALL cluster Germanium detectors and clean exit-channel gating afforded by a 31-element silicon ball used in conjunction with a 15-detector neutron wall allowed a revision and extension to the energy level schemes of all four nuclei up to J{sup {pi}}=31{sup -}/2. The difference in excitation energy between states of equivalent spin in the parent nucleus and its analogue partner have thus been established for both mirror pairs up to the f{sub 7/2}-shell band terminating state for the first time. This difference is assumed to be due almost entirely to the Coulomb effect and is therefore called the Coulomb energy difference (CED). The variation in the CED with spin has been interpreted as reflecting the ...

1998-10-01

317

Enabling Technology for Monitoring & Predicting Gas Turbine Health & Performance in IGCC Powerplants  

Energy Technology Data Exchange (ETDEWEB)

The ''Enabling & Information Technology To Increase RAM for Advanced Powerplants'' program, by DOE request, was re-directed, de-scoped to two tasks, shortened to a 2-year period of performance, and refocused to develop, validate and accelerate the commercial use of enabling materials technologies and sensors for coal/IGCC powerplants. The new program was re-titled ''Enabling Technology for Monitoring & Predicting Gas Turbine Health & Performance in IGCC Powerplants''. This final report summarizes the work accomplished from March 1, 2003 to March 31, 2004 on the four original tasks, and the work accomplished from April 1, 2004 to July 30, 2005 on the two re-directed tasks. The program Tasks are summarized below: Task 1--IGCC Environmental Impact on high Temperature Materials: The first task was refocused to address IGCC environmental impacts on high temperature materials used in gas turbines. This task ...

2005-12-01

318

Temperature-dependent properties of semiconductor quantum dots in coherent regime; Temperaturabhaengige Eigenschaften einzelner Halbleiter-Quantenpunkte im Kohaerenten Regime  

Energy Technology Data Exchange (ETDEWEB)

Recently, the public has become aware of keywords like ''Quantum computer'' or ''Quantum cryptography''. Regarding their potential application in solid state based quantum information processing and their overall benefit in fundamental research quantum dots have gained more and more public interest. In this context, quantum dots are often referred to as ''artificial atoms'', a term subsuming their physical properties quite nicely and emphasizing the huge potential for further investigations. The basic mechanism to be considered is the theoretical model of a two-level system. A quantum dot itself represents this kind of system quite nicely, provided that only the presence or absence of a single exciton in the ground state of that structure is regarded. This concept can also be expanded to the presence of two excitons (bi-exciton). Transitions between the relevant levels can be ...

2009-10-15