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J W Price

Publications and source records attributed to J W Price.

At least 19 recordsLinked to original sources
PubMed2005

Test of charge conjugation invariance.

We report on the first determination of upper limits on the branching ratio (BR) of eta decay to pi0pi0gamma and to pi0pi0pi0gamma. Both decay modes are strictly forbidden by charge conjugation (C) invariance. Using the Crystal Ball multiphoton detector, we obtained BR(eta-->pi0pi0gamma)<5 x 10(-4) at the 90% confidence level, in support of C invariance of isoscalar electromagnetic interactions of the light quarks. We have also measured BR(eta-->pi0pi0pi0gamma)<6 x 10(-5) at the 90% confidence level, in support of C invariance of isovector electromagnetic interactions.

Journal Article↗
PubMed2003

Dynamics of the pi(-)p-->pi(0)pi(0)n reaction for p(pi(-))<750 MeV/c.

Data are presented for the reaction pi(-)p-->pi(0)pi(0)n in the range from threshold to p(pi(-))=750 MeV/c. The systematics of the data and multipole analyses are examined for sensitivity to a f(0)(600) ("sigma") meson. A one-pion-exchange mechanism is found to be very weak, or absent. The reaction appears to become dominated by sequential pi(0) decays through the Delta(1232) resonance as the beam momentum increases, along with substantial interference effects from several competing mechanisms.

Journal Article↗
PubMed2001

Properties of the Lambda(1670)(1-)/2 resonance.

Recently the Crystal Ball Collaboration measured precise new data for the near-threshold reaction K(-)p-->etaLambda, which is dominated by formation of the Lambda(1670)1 / 2(-). In this Letter, we present results of a unitary, multichannel analysis that incorporates the new Crystal Ball data. For our preferred fit, we obtain mass M = 1673+/-2 MeV, width Gamma = 23+/-6 MeV, and elasticity x = 0.37+/-0.07. This elasticity is significantly larger than previously recognized. Resonance parameters of our preferred fit are in striking agreement with the quark-model predictions of Koniuk and Isgur.

Journal Article↗
PubMed2001

Determination of the quadratic slope parameter in eta-->3pi(0) decay.

We have determined the quadratic slope parameter alpha for eta-->3pi(0) to be alpha = -0.031(4) from a 99% pure sample of 10(6)eta-->3pi(0) decays produced in the reaction pi(-)p-->n(eta) close to the eta threshold using the Crystal Ball detector at the AGS. The result is four times more precise than the present world data and disagrees with current chiral perturbation theory calculations by about four standard deviations.

Journal Article↗
PubMed1976

Community screening for diabetes by blood glucose measurement. Results of a five-year experience.

The Diabetes Association of greater Cleveland screened 307,000 individuals in the metropolitan area for diabetes with a 75-gm. oral load of carbohydrate. Of these subjects 12,600 (4.1 per cent) had a two-capillary blood glucose level of greater than 139 mg. per cent and were defined as positive. Seventy per cent of the positives were retested, and 65 per cent of these again had two-hour levels greater than 139 mg. per cent. Seventy-one per cent of the original screening values were between 104 and 199 mg. per cent. The rate of positivity on retesting increased with the original screening bracket reaching 90 per cent at an original screening level of 240 mg. per cent or higher. The frequency of positive retests also increased with age irrespective of whether the original screening level was less than or greater than 200 mg. per cent. The implications of this large detection experience for conducting future mass surveys for diabetes are discussed.

Age Factors↗
PubMed1971

Formation and distribution of nuclear pore complexes in interphase.

The possibility of nuclear pore formation in the interphase nucleus was investigated in control and phytohemagglutinin (PHA) stimulated lymphocytes by the freeze-etching technique. 48 hr after the addition of PHA, the newly formed blasts which had not as yet divided had at least twice the number of pores per nucleus as controls. This clearly demonstrates that in lymphocytes nuclear pore formation can take place during interphase. It has generally been assumed that the distribution of nuclear pore complexes in somatic animal cells is random. However, we have utilized freeze etched rat kidney cells and a computer program to evaluate pore distribution. We find a minimum pore center-to-center spacing of approximately 1300 A and multiples thereof with high frequency. This is strong evidence for a nonrandom distribution of nuclear pores. The nonrandomness may be related to an underlying chromosomal organization in interphase. Using three criteria for identifying prospective pore sites (membrane specialization, nonrandomness, and alteration of heterochromatin distribution), we have found forming pores in sectioned material from cultured human melanoma cells. While nuclear pore formation may take place in conjunction with reformation of the nuclear membrane, a mechanism also exists for their formation during interphase.

Animals↗