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Spontaneous Carotid Artery Dissection Presenting as Trigeminal Neuralgia in the Emergency Department
Introduction: Carotid artery dissection (CAD) is a critical diagnosis in the emergency department (ED). Trigeminal neuralgia, while not uncommon, may cause the patient significant discomfort but generally is not attributed to severe morbidity and mortality.Case Report: We present a case of spontaneous CAD presenting with the classic intermittent âlightning-likeâ jaw and head pain suggestive of trigeminal neuralgia that was ultimately diagnosed utilizing computed tomography angiogram after multiple visits to the ED.Discussion: Coincidentally the patient had been started on anticoagulation a few days prior and no additional intervention was required.Conclusion: This case report discusses current recommendations for diagnosis, treatment, and long-term prognosis of CAD
Magnetic anisotropy in van-der-Waals ferromagnet VI3
A comprehensive study of magnetocrystalline anisotropy of a layered
van-der-Waals ferromagnet VI3 was performed. We measured angular dependences of
the torque and magnetization with respect to the direction of the applied
magnetic field within the "ac" plane perpendicular to and within the basal ab
plane, respectively. A two-fold butterfly-like signal was detected by
magnetization in the perpendicular "ac" plane. This signal symmetry remains
conserved throughout all magnetic regimes as well as through the known
structural transition down to the lowest temperatures. The maximum of the
magnetization signal and the resulting magnetization easy axis is significantly
tilted from the principal c axis by ~40{\deg}. The close relation of the
magnetocrystalline anisotropy to the crystal structure was documented. In
contrast, a two-fold-like angular signal was detected in the paramagnetic
region within the ab plane in the monoclinic phase, which transforms into a
six-fold-like signal below the Curie temperature TC. With further cooling,
another six-fold-like signal with an angular shift of ~30{\deg} grows
approaching TFM. Below TFM, in the triclinic phase, the original six-fold-like
signal vanishes, being replaced by a secondary six-fold-like signal with an
angular shift of ~30{\deg}.Comment: 14 pages, 10 figure
The 4.8 GHz LHC Schottky Pick-up System
The LHC Schottky observation system is based on traveling wave type high sensitivity pickup structures operating at 4.8 GHz. The choice of the structure and operating frequency is driven by the demanding LHC impedance requirements, where very low impedance is required below 2 GHz, and good sensitivity at the selected band at 4.8 GHz. A sophisticated filtering and triple down-mixing signal processing chain has been designed and implemented in order to achieve the specified 100 dB instantaneous dynamic range without range switching. Detailed design aspects for the complete systems and test results without beam are presented and discussed
Extremely low frequency magnetic fields emitted by cell phones
Cell phones expose significant parts of the human brain and head to extremely low frequency (ELF) magnetic fields (MF) classified by the IARC as a 2B carcinogen. ELF MF was measured on the front and back sides of 15 cell phones in standby, speaking, and listening modes for 2G and 3G standards in two frequency bands, LF1: 5 Hzâ200 Hz and LF2: 120 Hzâ10 kHz. The highest MF value was 70.03 ”T (RMS) in LF1 (2G, listening mode, front side) and 12.67 ”T (RMS) in LF2 (2G, speaking mode, front side). The 3G cell phones consistently emitted a lower ELF MF compared to the 2G ones. The exposure to ELF MF was also simulated at various locations (head, thorax, pelvis) using the CST Studio Suite. The simulations revealed 8.45 ”T, 7.5 ”T, and 6.09 ”T in the middle of the head (midbrain), 3.89 ”T, 3.98 ”T, and 2.83 ”T for the middle of the thorax (heart), and 2.03 ”T, 1.96 ”T, and 1.56 ”T in the middle of the pelvis (scrotum) for 10 Hz, 50 Hz, and 200 Hz, respectively. These values are comparable to those reported to induce biological and health effects, including those related to carcinogenesis. The results can be used in future studies concerning the ELF exposure or the combined effects of electromagnetic fields of radiofrequency and ELF
Identification of a Specific Vimentin Isoform That Induces an Antibody Response in Pancreatic Cancer
Pancreatic cancer has a poor prognosis, in part due to lack of early detection. The identification of circulating tumor antigens or their related autoantibodies provides a means for early cancer diagnosis. We have used a proteomic approach to identify proteins that commonly induce a humoral response in pancreatic cancer. Proteins from a pancreatic adenocarcinoma cell line (Panc-1) were subjected to two-dimensional PAGE, followed by Western blot analysis in which individual sera were tested for autoantibodies. Sera from 36 newly diagnosed patients with pancreatic cancer, 18 patients with chronic pancreatitis and 15 healthy subjects were analyzed. Autoantibodies were detected against a protein identified by mass spectrometry as vimentin, in sera from 16/36 patients with pancreatic cancer (44.4%). Only one of 18 chronic pancreatitis patients and none of the healthy controls exhibited reactivity against this vimentin isoform. Interestingly, none of several other isoforms of vimentin detectable in 2-D gels exhibited reactivity with patient sera. Vimentin protein expression levels were investigated by comparing the integrated intensity of spots visualized in 2-D PAGE gels of various cancers. Pancreatic tumor tissues showed greater than a 3-fold higher expression of total vimentin protein than did the lung, colon, and ovarian tumors that were analyzed. The specific antigenic isoform was found at 5â10 fold higher levels. The detection of autoantibodies to this specific isoform of vimentin may have utility for the early diagnosis of pancreatic cancer
Low-temperature spin dynamics of a valence bond glass in Ba<sub style="font-size: smaller; vertical-align: baseline; position: relative; top: 0.25em;">2YMoO<sub style="font-size: smaller; vertical-align: baseline; position: relative; top: 0.25em;">6</sub></sub>
We carried out AC magnetic susceptibility measurements and muon spin
relaxation spectroscopy on the cubic double perovskite Ba2YMoO6, down to 50 mK.
Below ~1 K the muon relaxation is typical of a magnetic insulator with a
spin-liquid type ground state, i.e. without broken symmetries or frozen
moments. However, the AC susceptibility revealed a dilute-spin-glass like
transition below ~ 1 K. Antiferromagnetically coupled Mo5+ 4d1 electrons in
triply degenerate t2g orbitals are in this material arranged in a geometrically
frustrated fcc lattice. Bulk magnetic susceptibility data has previously been
interpreted in terms of a freezing to a heterogeneous state with non-magnetic
sites where 4d^1 electrons have paired in spin-singlets dimers, and residual
unpaired Mo5+ 4d1 electrons. Based on the magnetic heat capacity data it has
been suggested that this heterogeneity is the result of kinetic constraints
intrinsic to the physics of the pure system (possibly due to topological
overprotection), leading to a self-induced glass of valence bonds between
neighbouring 4d1 electrons. The muSR relaxation unambiguously points to a
static heterogeneous state with a static arrangement of unpaired electrons
isolated by spin-singlet (valence bond) dimers between the majority of Mo5+ 4d
electrons. The AC susceptibility data indicate that the residual magnetic
moments freeze into a dilute-spin-glass-like state. This is in apparent
contradiction with the muon-spin decoupling at 50 mK in fields up to 200 mT,
which indicates that, remarkably, the time scale of the field fluctuations from
the residual moments is ~ 5 ns. Comparable behaviour has been observed in other
geometrically frustrated magnets with spin-liquid-like behaviour and the
implications of our observations on Ba2YMoO6 are discussed in this context.Comment: 11 pages, 3 Figures. Published in New Journal of Physic
System overview for the multi-element corrector magnets and controls for the Fermilab Booster
To better control the beam position, tune, and chromaticity in the Fermilab Booster synchrotron, a new package of six corrector elements has been designed, incorporating both normal and skew orientations of dipole, quadrupole, and sextupole magnets. The devices are under construction and will be installed in 48 locations in the Booster accelerator. Each of these 288 corrector magnets will be individually powered. Each of the magnets will be individually controlled using operator programmed current ramps designed specifically for each type of Booster acceleration cycle. This paper provides an overview of the corrector magnet installation in the accelerator enclosure, power and sensor interconnections, specifications for the switch-mode power supplies, rack and equipment layouts, controls and interlock electronics, and the features of the operator interface for programming the current ramps and adjusting the timing of the system triggers
Magnetic Properties and Mossbauer spectroscopy of NdFe(1-x)MnxO(3)
The effect of particle reduction to nanoscale size and substitution of Mn3+ ions for Fe3+ ions on the crystal structure, lattice dynamics, Mossbauer spectra and magnetic properties in NdFe(1-x)MnxO(3) compounds have been studied. X-ray powder diffraction and Raman spectroscopy revealed that the Jahn-Teller distortion of lattice dominates for samples with x GT 0.4. The average particle size of NdFeO3 nanoparticles (NAP) increases with annealing at 600 degrees C from about 15 nm to 25 nm. The presence of superparamagnetic particles was indicated by Mossbauer measurements in NdFeO3 NAP system. Sextets in NdFe(1-x)MnxO(3) Mssbauer spectra can be modelled with several local environments of Fe3+ induced by substitution. The reduction of dimensionality and the substitution induce a decrease of the Neel temperature T-Nl from 691 K to 544 K for NAP or to 356 K for x = 0.4, however the temperature of spin reorientation T-SR increases with substitution. The saturated magnetization obtained at 1.9 K increases and ferromagnetic component is removed below T-SR with the substitution.International Conference on Strongly Correlated Electron Systems (SCES), Jul 07-14, 2014, Univ Grenoble, Grenoble, Franc
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