We have been developing a Micro-Strip Gas Chamber (MSGC) with individual readouts for neutron scattering experiments. Performance requirements of a two-dimensional position sensitive neutron imaging ...detector for detecting an accurate Bragg-peak from a sample target include high spatial resolution, high detection efficiency, fast temporal response, and low gamma-ray sensitivity. To meet these specifications in addition to achieving a compact size in spite of the multi-channels in the gas based detector, we constructed a detector system that has a gas vessel with 541 channel feedthrough directly connecting to the data processing circuits. The developed detector system exhibited a pulse pair resolution of less than 1 mus, a spatial resolution of about 0.8 mm in full width at half maximum and good agreement between the position of incident neutron and measured peak position
The MEG II experiment, based at the Paul Scherrer Institut in Switzerland, reports the result of a search for the decay
μ
+
→
e
+
γ
from data taken in the first physics run in 2021. No excess of ...events over the expected background is observed, yielding an upper limit on the branching ratio of
B
(
μ
+
→
e
+
γ
)
<
7.5
×
10
-
13
(90% CL). The combination of this result and the limit obtained by MEG gives
B
(
μ
+
→
e
+
γ
)
<
3.1
×
10
-
13
(90% CL), which is the most stringent limit to date. A ten-fold larger sample of data is being collected during the years 2022–2023, and data-taking will continue in the coming years.
We introduced magnetoencephalography (MEG)-guided epilepsy surgery for children with intractable focal epilepsy at The Hospital for Sick Children (SickKids) in Toronto, Canada. Surgical candidacy and ...decisions on surgical procedure for children with intractable focal epilepsy are based on long-term scalp video EEG (VEEG) results, magnetic resonance imaging (MRI) findings, and the distribution of MEG spike sources. After multidisciplinary discussion at the seizure conference, for the patients requiring intracranial VEEG, custom-made subdural electrode grids are designed using three-dimensional MRI superimposed with MEG spike sources to cover the area of clustered MEG spike sources. At the first surgery, neurosurgeons use the intraoperative neuronavigation system to visualize the area of clustered spike dipoles and somatosensory evoked fields on MEG to place the subdural grid and depth electrodes. At the second surgery, the area of seizure onset and active interictal spike discharges on the intracranial VEEG recording, which usually correlates with the zone of clustered MEG spike sources, is resected. This combination leads to successful surgical outcome to control seizures in these challenging paediatric patients. MEG is a useful tool in children with intractable focal epilepsy to determine the surgical candidacy and focal cortical resection to stop seizures.
New type latch for hard disk drive KUWAJIMA, H; UENO, Y; UMEDA, M ...
Microsystem technologies,
05/2007, Volume:
13, Issue:
8-10
Conference Proceeding, Journal Article
Since geometries of semi-conductor devices continue to shrink, the requirement for each process becomes severer to keep uniformity of electrical parameters of the semi-conductor devices. A larger ...wafer also causes larger variations. Thus it has been strongly required for ion implantation process to compensate for the variations from other processes because of its good dose controllability. A newly developed mapping of intentional non-uniform dosage system, which is named 'MIND system,' is implemented in SEN's single-wafer-type implanters. The MIND system controls both horizontal and vertical scan speed simultaneously. Intentional two-dimensional non-uniform profiles of sheet resistance, such as concentric and eccentric profiles, are obtained only by single-step ion implantation.
Operation and performance of the MEG II detector Afanaciev, K.; Baldini, A. M.; Ban, S. ...
The European physical journal. C, Particles and fields,
02/2024, Volume:
84, Issue:
2
Journal Article
Peer reviewed
Open access
The MEG II experiment, located at the Paul Scherrer Institut (PSI) in Switzerland, is the successor to the MEG experiment, which completed data taking in 2013. MEG II started fully operational data ...taking in 2021, with the goal of improving the sensitivity of the
μ
+
→
e
+
γ
decay down to
∼
6
×
10
-
14
almost an order of magnitude better than the current limit. In this paper, we describe the operation and performance of the experiment and give a new estimate of its sensitivity versus data acquisition time.
The kinetics of Staphylococcal enterotoxin B-(SEB) induced peripheral tolerance has been investigated. Ten days after SEB injection, thymectomized BALB/cByJ mice showed suppressed spleen cell ...proliferative responses to SEB. After 2 mo the SEB-specific response was partly recovered. Four months later the response of spleen cells of SEB-primed mice was comparable to those of control mice. The proportion of CD4+, V beta 8+ T cells was diminished in the tolerized mice and was not restored even after the response was recovered. Purified CD4+, V beta 8+ T cells from SEB-primed mice after 4 mo responded similarly to SEB as control CD4+, V beta 8+ T cells. These expressed a similar profile of surface markers compared with that of unprimed control cells, except a homing receptor was slightly lower. An experiment that addressed the possibility that non-anergic T cells expand over time and are in fact responsible for the recovery of the proliferative response showed that such events unlikely occur in vivo. Therefore, the data indicate that T cell anergy is reversible in vivo. It is also suggested that the challenge with superantigen results in neither clonal expansion nor specific CD4+, V beta 8+ T cell memory.
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