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M Earl

Publications and source records attributed to M Earl.

15 recordsLinked to original sources
PubMed2004

Limits on the neutrino magnetic moment using 1496 days of Super-Kamiokande-I solar neutrino data.

A search for a nonzero neutrino magnetic moment has been conducted using 1496 live days of solar neutrino data from Super-Kamiokande-I. Specifically, we searched for distortions to the energy spectrum of recoil electrons arising from magnetic scattering due to a nonzero neutrino magnetic moment. In the absence of a clear signal, we found micro(nu)</=(3.6x10(-10))micro(B) at 90% C.L. by fitting to the Super-Kamiokande day-night spectra. The fitting took into account the effect of neutrino oscillation on the shapes of energy spectra. With additional information from other solar neutrino and KamLAND experiments constraining the oscillation region, a limit of micro(nu)</=(1.1x10(-10))micro(B) at 90% C.L. was obtained.

Journal Article↗
PubMed2003

Search for nu(e) from the sun at Super-Kamiokande-I.

We present the results of a search for low energy nu(e) from the Sun using 1496 days of data from Super-Kamiokande-I. We observe no significant excess of events and set an upper limit for the conversion probability to nu(e) of the 8B solar neutrino. This conversion limit is 0.8% (90% C.L.) of the standard solar model's neutrino flux for total energy=8-20 MeV. We also set a flux limit for monochromatic nu(e) for E(nu(e))=10-17 MeV.

Journal Article↗
PubMed2003

Search for supernova relic neutrinos at Super-Kamiokande.

A search for the relic neutrinos from all past core-collapse supernovae was conducted using 1496 days of data from the Super-Kamiokande detector. This analysis looked for electron-type antineutrinos that had produced a positron with an energy greater than 18 MeV. In the absence of a signal, 90% C.L. upper limits on the total flux were set for several theoretical models; these limits ranged from 20 to 130 macro nu(e) cm(-2) s(-1). Additionally, an upper bound of 1.2 macro nu(e) cm(-2) s(-1) was set for the supernova relic neutrino flux in the energy region E(nu)>19.3 MeV.

Journal Article↗
PubMed2001

Optimized intensity-modulated arc therapy for prostate cancer treatment.

We recently implemented intensity-modulated arc therapy (IMAT) at our institution. In this study, we evaluate the dosimetric merits of the application of this technique to the treatment of prostate cancer. Each IMAT treatment plan incorporated bilateral overlapping arcs. The dose from each beam segment was computed using the three-dimensional dose model of a clinical treatment planning system (Render Plan 3.5, Precision Therapy). The weights assigned to the individual arc segments were optimized using a gradient search method. For 12 patients, comparisons were made between the IMAT treatment plans and corresponding plans using fixed cone-beam intensity-modulated radiotherapy (IMRT) from a commercial inverse planning system (CORVUS, NOMOS Corp.). We found that the optimized IMAT treatments produced similar dose distributions to the IMRT deliveries. Compared with the IMRT treatments, the IMAT treatments produced slightly less target dose homogeneity with consistently greater sparing of the rectum in regions of lower dose. The trade-off between target dose conformity and rectum sparing can be adjusted in both optimization procedures. Because the total beam-on time for IMAT delivery is 1 to 2 minutes with approximately 5-6 minutes of patient setup time, the delivery efficiency of the IMAT treatment was significantly better than the multiple-beam IMRT treatment.

Humans↗
PubMed2001

Solar 8B and hep neutrino measurements from 1258 days of Super-Kamiokande data.

Solar neutrino measurements from 1258 days of data from the Super-Kamiokande detector are presented. The measurements are based on recoil electrons in the energy range 5.0-20.0 MeV. The measured solar neutrino flux is 2.32+/-0.03(stat)+0.08-0.07(syst)x10(6) cm(-2) x s(-1), which is 45.1+/-0.5(stat)+1.6-1.4(syst)% of that predicted by the BP2000 SSM. The day vs night flux asymmetry (Phi(n)-Phi(d))/Phi(average) is 0.033+/-0.022(stat)+0.013-0.012(syst). The recoil electron energy spectrum is consistent with no spectral distortion. For the hep neutrino flux, we set a 90% C.L. upper limit of 40x10(3) cm(-2) x s(-1), which is 4.3 times the BP2000 SSM prediction.

Journal Article↗
PubMed2001

Constraints on neutrino oscillations using 1258 days of Super-Kamiokande solar neutrino data.

We report the result of a search for neutrino oscillations using precise measurements of the recoil electron energy spectrum and zenith angle variations of the solar neutrino flux from 1258 days of neutrino-electron scattering data in Super-Kamiokande. The absence of significant zenith angle variation and spectrum distortion places strong constraints on neutrino mixing and mass difference in a flux-independent way. Using the Super-Kamiokande flux measurement in addition, two allowed regions at large mixing are found.

Journal Article↗
PubMed2000

Tau neutrinos favored over sterile neutrinos in atmospheric muon neutrino oscillations.

The previously published atmospheric neutrino data did not distinguish whether muon neutrinos were oscillating into tau neutrinos or sterile neutrinos, as both hypotheses fit the data. Using data recorded in 1100 live days of the Super-Kamiokande detector, we use three complementary data samples to study the difference in zenith angle distribution due to neutral currents and matter effects. We find no evidence favoring sterile neutrinos, and reject the hypothesis at the 99% confidence level. On the other hand, we find that oscillation between muon and tau neutrinos suffices to explain all the results in hand.

Journal Article↗
PubMed2000

Unit to unit variation of pesticide residues--options for acute dietary risk assessment.

Within the context of the current UK policy for those commodities where the potential variability of residues in individual commodity units is taken into account, a variability factor nu, which reflects the ratio of a high level residue in the individual commodity unit to the corresponding composite residue level, is used. Data gathered from supervised industry trials in which individual items were analysed following treatment, although limited, show that variability is typically lower than that reflected by the default factors currently used and that the range of variability is reproducible over the limited range of different a.i./crop/method of application combinations investigated. In order to improve the accuracy of the acute dietary exposure estimate, the European Crop Protection Association (ECPA) proposes the following alternative to the current Tier I approach. The residue level input from a 'hot' unit within the dietary risk assessment should be determined using the highest composite sample residue from supervised field trials and a generic variability factor (nu) determined experimentally from supervised trials. The variability factor itself should be calculated as the 95th percentile level of the residue level found in an individual unit (or single serving portion for large crops) divided by sample mean for data produced from supervised trials. This would improve the accuracy of the Tier I approach and allow attention to be focused on particular a.i./crop/method of application combinations where the NESTI > acute RfD (based on a Tier I assessment) and generation of individual unit residue data for the particular outlet or other mitigation may be appropriate.

Diet↗
PubMed1998

Cytological changes in endotracheal aspirates associated with chronic lung disease.

Endotracheal aspirates taken serially from mechanically ventilated premature infants born at < 28 weeks gestation between March 1992 and August 1993 were studied to determine whether early cytological changes would be a good predictor of lung damage in infants who develop chronic lung disease (CLD). CLD was diagnosed if the infant required supplemental oxygen at 36 weeks corrected gestational age. Fifty-five infants were enrolled in the study, five died and of the 50 infants remaining, 17 (34%) developed CLD. The infants with CLD had a significantly lower gestation (25.5 +/- 1.8 (mean +/- 1 SD) versus 26.2 +/- 0.9 weeks, p < 0.05), significantly more required surfactant (14/17 vs. 16/33, p < 0.05) and were ventilated for a significantly longer period (43.3 +/- 26.6 vs. 19.3 +/- 12.8 days, p < 0.0001). Endotracheal aspirate cytology showed that infants with CLD had significantly more degenerated columnar epithelial cells on day 3 (p = 0.001), and more neutrophils on day 10 (p = 0.007). Though not predictive of CLD, cytological changes consistent with bronchial epithelial and pulmonary damage followed by an inflammatory response were found in the tracheal aspirates of a group of infants clinically diagnosed with CLD.

Chronic Disease↗
PubMed1990

Coordination of posture and movement.

Movement is performed against a background of subtle postural adjustments that counteract destabilizing forces imposed by the movement. Despite the importance of these postural adjustments to the safe and efficient performance of movement, little is known about the properties of these postural accompaniments. The purpose of this article is twofold. First, it provides a review of properties of postural adjustments that accompany a variety of limb and trunk movements. Second, a schema for the coordination of posture and movement is proposed. This schema suggests that a central nervous system model of body dynamics is essential to anticipatory control of posture during movement.

Biomechanical Phenomena↗
PubMed1988

Early diagnosis of rejection of canine pancreas allografts by fine-needle aspiration biopsy.

In pancreatic allograft transplantation with bladder exocrine drainage, falls in urinary amylase (UA) levels have been shown to be an earlier marker of rejection than rises in fasting blood glucose levels. Nevertheless, this is often too late for reversal of the rejection process. In an attempt to diagnose rejection earlier, fine-needle aspiration biopsy was correlated with UA and graft histology. Sixteen dogs were given total pancreatic allografts, 10 without immunosuppression and 6 with triple therapy. FNAB and needle-core biopsies were performed on days 0, 2, 4, 7, 9, 24, and 30 and/or at functional rejection, defined as a fasting UA level of less than 5000 IU/L. Cytocentrifuge preparations of the FNABs were evaluated by total corrected increment (TCI) scores. These increased significantly from 1.0 (+/- 0.4; mean +/- SEM) 6 days, to 3.0 (+/- 1.2) 4 days before functional rejection. The increase was due to the presence of blast cells and macrophages. The TCI of healthy immunosuppressed grafts remained below 1.6 for 30 days after transplantation and was greater than 5.0 when pancreatitis or acute rejection was seen on conventional histology. Minimal histologic change had significantly lower TCI scores than both acute rejection (P less than 0.01) and pancreatitis (P less than 0.001). Acute rejection and pancreatitis were distinguished by a significant difference in increments of monocytes/lymphocytes and macrophages. In contrast to FNAB, UA levels did not differentiate minimal change from acute rejection but were a reliable marker of end-stage rejection.

Amylases↗
PubMedDate not supplied

The right mind-set for managing information technology.

Too many managers in the West are intimidated by the task of managing technology. They tiptoe around it, supposing that it needs special tools, special strategies, and a special mind-set. Well, it doesn't, the authors say. Technology should be managed-controlled, even--like any other competitive weapon in a manager's arsenal. The authors came to this conclusion in a surprising way. Having set out to compare Western and Japanese IT-management practices, they were startled to discover that Japanese companies rarely experience the IT problems so common in the United States and Europe. In fact, their senior executives didn't even recognize the problems that the authors described. When they dug deeper into 20 leading companies that the Japanese themselves consider exemplary IT users, they found that the Japanese see IT as just one competitive lever among many. Its purpose, very simply, is to help the organization achieve its operational goals. The authors recognize that their message is counterintuitive, to say the least. In visits to Japan, Western executives have found anything but a model to copy. But a closer look reveals that the prevailing wisdom is wrong. The authors found five principles of IT management in Japan that, they believe, are not only powerful but also universal. M. Bensaou and Michael Earl contrast these principles against the practices commonly found in Western companies. While acknowledging that Japan has its own weaknesses with technology, particularly in white-collar office settings, they nevertheless urge senior managers in the West to consider the solid foundation on which Japanese IT management rests.

Decision Making, Organizational↗