The experiment E94-107 in Hall A at Jefferson Lab started a systematic study of high resolution hypernuclear spectroscopy in the 0p-shell region of nuclei such as the hypernuclei produced in ...electroproduction on 9Be, 12C and 16O targets. In order to increase counting rates and provide unambiguous kaon identification two superconducting septum magnets and a ring-imaging Cherenkov detector were added to the Hall A standard equipment. The high-quality beam, the good spectrometers and the new experimental devices allowed us to obtain very good results. For the first time, measurable strength with sub-MeV energy resolution was observed for the core-excited states of Lambda 12B. A high-quality Lambda 16N hypernuclear spectrum was likewise obtained. A first measurement of the Lambda binding energy for Lambda 16N, calibrated against the elementary reaction on hydrogen, was obtained with high precision, 13.76 +/- 0.16 MeV. Similarly, the first Lambda 9Li hypernuclear spectrum shows general agreement with theory (distorted-wave impulse approximation with the SLA and BS3 electroproduction models and shell-model wave functions). Some disagreement exists with respect to the relative strength of the states making up the first multiplet. A Lambda separation energy of 8.36 MeV was obtained, in agreement with previous results. It has been shown that the electroproduction of hypernuclei can provide information complementary to that obtained with hadronic probes and the gamma-ray spectroscopy technique.
Phased‐Array Intracardiac Echocardiography for AF Ablation.
Introduction: Fluoroscopic imaging provides limited anatomic guidance for left atrial structures. The aim of this study was to determine ...the utility of real‐time, phased‐array intracardiac echocardiography during radiofrequency ablation for atrial fibrillation.
Methods and Results: In 29 patients undergoing pulmonary vein isolation (n = 16) or linear (n = 13) left atrial radiofrequency ablation for atrial fibrillation, intracardiac phased‐array echocardiography was used to visualize left atrial anatomy and the pulmonary veins, as well as ablation and mapping catheters during ablation procedures. In the 16 pulmonary vein isolation patients, the mean pulmonary vein ostial diameters measured by venography and intracardiac echocardiography were similar for all veins positions, except that left common pulmonary vein diameters were larger as measured by echocardiography (2.50 ± 0.29 cm) than by venography (1.79 ± 0.50 cm, P = 0.001). The ostial diameters measured by echocardiography and venography were not correlated, however (r = 0.23, P = 0.19). As directed by echocardiography, only 1 of 25 circular mapping catheters (4%) used in 16 patients was replaced due to inappropriate sizing of the pulmonary veins. Mean pulmonary vein Doppler flow velocities increased after ablation for left‐sided veins but ostial diameters were unchanged. In the linear ablation patients, the entire extent of the linear electrode array could be visualized in only 3 of 52 of catheter positions (6%) in the 13 patients. A portion of the catheter could be seen in only 50% of all target catheter positions.
Conclusion: Phased‐array intracardiac echocardiography (1) allows sizing and positioning of pulmonary vein mapping catheters, (2) provides measures of pulmonary vein ostial diameters, (3) continuously monitors pulmonary vein Doppler flow velocities, and (4) has limited use in positioning linear ablation catheters in the left atrium.
We present Spitzer/IRAC observations of nine z'-band dropouts highly magnified (2 less than or similar to mu less than or similar to 12) by the Bullet Cluster. We combine archival imaging with our ...Exploratory program (SURFS UP), which results in a total integration time of similar to 30 hr per Infrared Array Camera (IRAC) band. We detect (greater than or similar to 3 sigma) in both IRAC bands the brightest of these high-redshift galaxies, with 3.6 = 23.80 +/- 0.28 mag, 4.5 = 23.78 +/- 0.25 mag, and (H - 3.6) = 1.17 +/- 0.32 mag. The remaining eight galaxies are undetected to 3.6 similar to 26.4 mag and 4.5 similar to 26.0 mag with stellar masses of similar to 5 x 10(7) M-circle dot. The detected galaxy has an estimated magnification of mu = 12 +/- 4, which implies this galaxy has an ultraviolet luminosity of L-1500 similar to 0.3 Lz-7*-the lowest-luminosity individual source detected in IRAC at z greater than or similar to 7. By modeling the broadband photometry, we estimate the galaxy has an intrinsic star formation rate (SFR) of SFR similar to 1.3 M-circle dot yr(-1) and stellar mass of M similar to 2.0 x 10(9) M-circle dot, which gives a specific star formation rate of sSFR similar to 0.7 Gyr(-1). If this galaxy had sustained this SFR since z similar to 20, it could have formed the observed stellar mass (to within a factor of similar to 2). We also discuss alternate star formation histories and argue that the exponentially increasing model is unlikely. Finally, based on the intrinsic SFR, we estimate that this galaxy has a likely C II flux of \textless f(C II)\textgreater = 1.6 mJy.
In a videotaped free-play session with a parent, autistic children were compared with mental-age matched Developmental Language Delay (DLD) children and with normally developing (ND) 2-year-olds in ...the use of communicative acts by parent and child. Groups were matched for language level. Autistic children had more incidents of no responses, produced less affirming, turn-taking vocalization, and gesture, and were less likely to initiate communication than other children. Parent groups differed only in a greater amount of initiating and use of imperatives by parents of autistic children. Few relations between parent behaviors and child behaviors were found. Nonresponses by all children were concentrated subsequent to parent imperatives and questions, but no group differences were found in the distribution of nonresponses to various parent communicative acts. Results are interpreted to support the hypothesis that autistic children's language can serve a number of useful functions but that their pattern of language functions differs from that of nonautistic language-impaired children and much younger normal children of similar language level.
An experiment measuring electroproduction of hypernuclei has been performed in hall A at Jefferson Lab on a 12C target. In order to increase counting rates and provide unambiguous kaon identification ...two superconducting septum magnets and a ring imaging Cherenkov detector were added to the hall A standard equipment. An unprecedented energy resolution of less than 700 keV FWHM has been achieved. Thus, the observed (Lambda)(12)B spectrum shows for the first time identifiable strength in the core-excited region between the ground-state s-wave Lambda peak and the 11 MeV p-wave Lambda peak.
The fate of phosphorus contained in waste activated sludges from a biological nutrient removal plant was investigated in pilot-scale, co-digestion studies at a full-scale wastewater treatment plant. ...In these studies, co-digestion of primary fermenter and waste activated sludges resulted in a significant release of the biologically-bound sludge phosphorus. As much as 80% of phosphate removed during treatment was released to the supernatant during anaerobic digestion. Phosphate release was found to be independent of digester hydraulic retention time at the values tested (20 vs. 10 day). Co-digestion also impacted other aspects of digester operation, including volatile solids reduction and total gas and methane production. Jar tests, conducted to evaluate the efficiency of various chemical treatment methods for removing phosphate from digester supernatants, revealed that lime, alum and ferric chloride all proved equally effective. Overall, ferric chloride at a dosage of 2 g l
−1
was found to be the most effective method for combined removal of phosphorus, COD and TSS.
To examine the association between presence, severity, and extent of lesions of age-related macular degeneration (AMD) and optic disk and cup diameters in a general population.
Cross-sectional study.
...setting:
Population-based.
study population:
Adults aged 43 to 86 years participating in the Beaver Dam Eye Study.
observation procedures:
Fundus photographs were graded for lesions of AMD using standard protocols. The photographs were obtained during the baseline examination of the Beaver Dam Eye Study.
main outcome measure:
Optic disk cupping as related to presence, severity, and extent of lesions of AMD.
There were no significant differences in the vertical optic disk and cup measurements or in the vertical cup to disk ratios by severity of lesions of AMD (
P values all greater than .10). In those eyes with late lesions of AMD, there was no association of the size of the lesions or their distribution in the fundus and the extent of cupping.
From a population perspective, there is no relationship of the presence or severity of AMD and optic disk cupping.
Whether responding to a CNN.com survey or voting for the NFL All-Pro team, computer users are becoming more and more comfortable with Internet polls. Computer use in the United States continues to ...grow-more than half of all American households now have a personal computer. The next question, then, becomes obvious. Should Americans be able to use the Internet in the most important polls of all? Some advocates of Internet voting argue that Americans are well suited to casting their ballots online in political elections. They are eager to make use of new technology, and they have relatively broad access to the Internet. Voting would become easier for people stuck at home, at the office, or on the road. Internet voting might encourage greater political participation among young adults, a group that stays away from the polling place in droves. It would hold special appeal for military personnel overseas, whose ability to vote is a growing concern. There are serious concerns, however, regarding computer security and voter fraud, unequal Internet access across socioeconomic lines (the "digital divide"), and the civic consequences of moving elections away from schools and other polling places and into private homes and offices. After all, showing up to vote is the most public civic activity many Americans engage in, and it is often their only overt participation in the democratic process. In Point, Click, and Vote, voting experts Michael Alvarez and Thad Hall make a strong case for greater experimentation with Internet voting. In their words, "There is no way to know whether any argument regarding Internet voting is accurate unless real Internet voting systems are tested, and they should be tested in small-scale, scientific trials so that their successes and failures can be evaluated." In other words, you never know until you try, and it's time to try harder. The authors offer a realistic plan for putting pilot remote Internet voting programs into effect n
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