114 research outputs found
Imaging the passionate stage of romantic love by dopamine dynamics.
Using [(11)C]raclopride, a dopamine D2/D3 receptor antagonist, we undertook a positron emission tomography (PET) study to investigate the involvement of the dopaminergic neurotransmitter system when subjects viewed the pictures of partners to whom they were romantically attached. Ten subjects viewed pictures of their romantic partners and, as a control, of friends of the same sex for whom they had neutral feelings during the PET study. We administered [(11)C]raclopride to subjects using a timing for injecting the antagonist which had been determined in previous studies to be optimal for detecting increases in the amount of dopamine released by stimulation. The results demonstrated statistically significant activation of the dopaminergic system in two regions, the medial orbitofrontal cortex (mOFC) and medial prefrontal cortex, the former of which has been strongly implicated in a variety of rewarding experiences, including that of beauty and love. A positive correlation was obtained in mOFC between excitement levels and dopaminergic activation only in the love but not in the control condition
Search for Anisotropy of Ultra-High Energy Cosmic Rays with the Telescope Array Experiment
We study the anisotropy of Ultra-High Energy Cosmic Ray (UHECR) events
collected by the Telescope Array (TA) detector in the first 40 months of
operation. Following earlier studies, we examine event sets with energy
thresholds of 10 EeV, 40 EeV, and 57 EeV. We find that the distributions of the
events in right ascension and declination are compatible with an isotropic
distribution in all three sets. We then compare with previously reported
clustering of the UHECR events at small angular scales. No significant
clustering is found in the TA data. We then check the events with E>57 EeV for
correlations with nearby active galactic nuclei. No significant correlation is
found. Finally, we examine all three sets for correlations with the large-scale
structure of the Universe. We find that the two higher-energy sets are
compatible with both an isotropic distribution and the hypothesis that UHECR
sources follow the matter distribution of the Universe (the LSS hypothesis),
while the event set with E>10 EeV is compatible with isotropy and is not
compatible with the LSS hypothesis at 95% CL unless large deflection angles are
also assumed. We show that accounting for UHECR deflections in a realistic
model of the Galactic magnetic field can make this set compatible with the LSS
hypothesis.Comment: 10 pages, 9 figure
Flowcharts for the diagnosis and treatment of acute cholangitis and cholecystitis: Tokyo Guidelines
Diagnostic and therapeutic strategies for acute biliary inflammation/ infection (acute cholangitis and acute cholecystitis), according to severity grade, have not yet been established in the world. Therefore we formulated flowcharts for the management of acute biliary inflammation/ infection in accordance with severity grade. For mild (grade I) acute cholangitis, medical treatment may be sufficient/appropriate. For moderate (grade II) acute cholangitis, early biliary drainage should be performed. For severe (grade III) acute cholangitis, appropriate organ support such as ventilatory/circulatory management is required. After hemodynamic stabilization is achieved, urgent endoscopic or percutaneous transhepatic biliary drainage should be performed. For patients with acute cholangitis of any grade of severity, treatment for the underlying etiology, including endoscopic, percutaneous, or surgical treatment should be performed after the patient's general condition has improved. For patients with mild (grade I) cholecystitis, early laparoscopic cholecystectomy is the preferred treatment. For patients with moderate (grade II) acute cholecystitis, early laparoscopic or open cholecystectomy is preferred. In patients with extensive local inflammation, elective cholecystectomy is recommended after initial management with percutaneous gallbladder drainage and/or cholecystostomy. For the patient with severe (grade III) acute cholecystitis, multiorgan support is a critical part of management. Biliary peritonitis due to perforation of the gallbladder is an indication for urgent cholecystectomy and/or drainage. Delayed elective cholecystectomy may be performed after initial treatment with gallbladder drainage and improvement of the patient's general medical condition. © Springer-Verlag Tokyo 2007.published_or_final_versio
Observed magnetic resonance imaging changes in pediatric patients treated with stereotactic radiosurgery for intracranial tumors
Sexual Inequality in Tuberculosis
Olivier Neyrolles and Lluis Quintana-Murci review the evidence on why tuberulosis notification is twice as high in men as in women in most countries
Upper limit on the flux of photons with energies above 10(19) eV using the Telescope Array surface detector
We search for ultra-high energy photons by analyzing geometrical properties of shower fronts of events registered by the Telescope Array surface detector. By making use of an event-by-event statistical method, we derive upper limits on the absolute flux of primary photons with energies above 1019, 1019.5, and 1020 eV based on the first three years of data takenopen4
CORRELATIONS OF THE ARRIVAL DIRECTIONS OF ULTRA-HIGH ENERGY COSMIC RAYS WITH EXTRAGALACTIC OBJECTS AS OBSERVED BY THE TELESCOPE ARRAY EXPERIMENT
We search for correlations between the positions of extragalactic objects and the arrival directions of ultra-high energy cosmic rays (UHECRs) with primary energy E ??? 40 EeV as observed by the surface detector array of the Telescope Array (TA) experiment during the first 40 months of operation. We examine several public astronomical object catalogs, including the Veron-Cetty and Veron catalog of active galactic nuclei. We count the number of TA events correlated with objects in each catalog as a function of three parameters: the maximum angular separation between a TA event and an object, the minimum energy of the events, and the maximum redshift of the objects. We determine the combination of these parameters that maximizes the correlations, and we calculate the probability of having the same levels of correlations from an isotropic distribution of UHECR arrival directions. No statistically significant correlations are found when penalties for scanning over the above parameters and for searching in several catalogs are taken into account.open4
The Cosmic Ray Energy Spectrum Observed with the Surface Detector of the Telescope Array Experiment
The Telescope Array (TA) collaboration has measured the energy spectrum of
ultra-high energy cosmic rays with primary energies above 1.6 x 10^(18) eV.
This measurement is based upon four years of observation by the surface
detector component of TA. The spectrum shows a dip at an energy of 4.6 x
10^(18) eV and a steepening at 5.4 x 10^(19) eV which is consistent with the
expectation from the GZK cutoff. We present the results of a technique, new to
the analysis of ultra-high energy cosmic ray surface detector data, that
involves generating a complete simulation of ultra-high energy cosmic rays
striking the TA surface detector. The procedure starts with shower simulations
using the CORSIKA Monte Carlo program where we have solved the problems caused
by use of the "thinning" approximation. This simulation method allows us to
make an accurate calculation of the acceptance of the detector for the energies
concerned.Comment: Accepted for publication by Astrophysical Journal Letter
The surface detector array of the Telescope Array experiment
The Telescope Array (TA) experiment, located in the western desert of
Utah,USA, is designed for observation of extensive air showers from extremely
high energy cosmic rays. The experiment has a surface detector array surrounded
by three fluorescence detectors to enable simultaneous detection of shower
particles at ground level and fluorescence photons along the shower track. The
TA surface detectors and fluorescence detectors started full hybrid observation
in March, 2008. In this article we describe the design and technical features
of the TA surface detector.Comment: 32 pages, 17 figure
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