22 research outputs found
Maine\u27s Science and Engineering Brain Drain: How Much and Why?
More than the traditional economic ingredients, the new global economy is being built around talented people with special knowledge and skills, those with the capacity to innovate and the entrepreneurial wherewithal to turn ideas into commercial products. Hence many states are shifting economic development strategies away from efforts that market commodities such as low tax rates and cheap labor, and toward efforts that amass and equip talented people with the tools of innovation. In short, states are beginning to think about strategies for recruiting and/or retaining talented workers. In this regard, the Southern Technology Council conducted a national study to compare states on their performance in retaining their own recent science and engineering graduates and/or attracting similar graduates from states elsewhere in the country. How is Maine doing? they ask. In a word, poorly. The authors compare Maine to other states on a number of performance indicators and predictor variables to assess why this is so. They suggest Maine take bold steps now to prevent the continued loss of its most important commodity of the future
Measurements of the charge ratio and polarization of cosmic-ray muons with the Super-Kamiokande detector
We present the results of the charge ratio () and polarization
() measurements using the decay electron events collected from
2008 September to 2022 June by the Super-Kamiokande detector. Because of its
underground location and long operation, we performed high precision
measurements by accumulating cosmic-ray muons. We measured the muon charge
ratio to be at
, where
is the muon energy and is the zenith angle
of incoming cosmic-ray muons. This result is consistent with the Honda flux
model while this suggests a tension with the model of . We
also measured the muon polarization at the production location to be
at the muon
momentum of at the surface of the
mountain; this also suggests a tension with the Honda flux model of
. This is the most precise measurement ever to experimentally
determine the cosmic-ray muon polarization near . These
measurement results are useful to improve the atmospheric neutrino simulations.Comment: 29 pages, 45 figure
Search for Periodic Time Variations of the Solar B Neutrino Flux Between 1996 and 2018 in Super-Kamiokande
We report a search for time variations of the solar B neutrino flux using
5,804 live days of Super-Kamiokande data collected between May 31, 1996, and
May 30, 2018. Super-Kamiokande measured the precise time of each solar neutrino
interaction over 22 calendar years to search for solar neutrino flux
modulations with unprecedented precision. Periodic modulations are searched for
in a data set comprised of five-day interval solar neutrino flux measurements
with a maximum likelihood method. We also applied the Lomb-Scargle method to
this data set to compare it with previous reports. The only significant
modulation found is due to the elliptic orbit of the Earth around the Sun. The
observed modulation is consistent with astronomical data: we measured an
eccentricity of (1.530.35)\,\%, and a perihelion shift is
(1.513.5)\,days.Comment: 8 pages, 5 figures, 2 tables, and data file:
"sksolartimevariation5804d.txt
Measurements of the charge ratio and polarization of cosmic-ray muons with the Super-Kamiokande detector
We present the results of the charge ratio (R) and polarization (Pμ0) measurements using the decay electron events collected from 2008 September to 2022 June by the Super-Kamiokande detector. Because of its underground location and long operation, we performed high precision measurements by accumulating cosmic-ray muons. We measured the muon charge ratio to be R=1.32±0.02 (stat.+syst.) at EμcosθZenith=0.7+0.3−0.2 TeV, where Eμ is the muon energy and θZenith is the zenith angle of incoming cosmic-ray muons. This result is consistent with the Honda flux model while this suggests a tension with the πK model of 1.9σ. We also measured the muon polarization at the production location to be Pμ0=0.52±0.02 (stat.+syst.) at the muon momentum of 0.9+0.6−0.1 TeV/c at the surface of the mountain; this also suggests a tension with the Honda flux model of 1.5σ. This is the most precise measurement ever to experimentally determine the cosmic-ray muon polarization near 1 TeV/c. These measurement results are useful to improve the atmospheric neutrino simulations
Recurrence of Postoperative Stress-Induced Cardiomyopathy Resulting from Status Epilepticus
Introduction. Classically, stress-induced cardiomyopathy (SIC), also known as takotsubo cardiomyopathy, displays the pathognomonic feature of reversible left ventricular apical ballooning without coronary artery stenosis following stressful event(s). Temporary reduction in ejection fraction (EF) resolves spontaneously. Variants of SIC exhibiting mid-ventricular regional wall motion abnormalities have been identified. Recent case series present SIC as a finding in association with sudden unexplained death in epilepsy (SUDEP). This case presents a patient who develops recurrence of nonapical cardiomyopathy secondary to status epilepticus. Case Report. Involving a postoperative, postmenopausal woman having two distinct episodes of status epilepticus (SE) preceding two incidents of SIC. Preoperative transthoracic echocardiogram (TTE) confirms the patient’s baseline EF of 60% prior to the second event. Postoperatively, SE occurs, and the initial electrocardiogram exhibits T-wave inversions with subsequent elevation of troponin I. Postoperative TTE shows an EF of 30% with mid-ventricular wall akinesia restoring baseline EF rapidly. Conclusion. This case identifies the need to understand SIC and its diagnostic criteria, especially when cardiac catheterization is neither indicated nor available. Sudden cardiac death should be considered as a possible complication of refractory status epilepticus. The pathophysiology in SUDEP is currently unknown; yet a correlation between SUDEP and SIC is hypothesized to exist