1,007 research outputs found
Simultaneously optimizing the interdependent thermoelectric parameters in Ce(NiCu)Al
Substitution of Cu for Ni in the Kondo lattice system CeNiAl results
in a simultaneous optimization of the three interdependent thermoelectric
parameters: thermoelectric power, electrical and thermal conductivities, where
the electronic change in conduction band induced by the extra electron of Cu is
shown to be crucial. The obtained thermoelectric figure of merit amounts
to 0.125 at around 100 K, comparable to the best values known for Kondo
compounds. The realization of ideal thermoelectric optimization in
Ce(NiCu)Al indicates that proper electronic tuning of Kondo
compounds is a promising approach to efficient thermoelectric materials for
cryogenic application.Comment: 4 pages, 4 figures. Accepted for publication in Physical Review
A Flash Flood Control System Based on the Global Earth Observation System of Systems
Source: ICHE Conference Archive - https://mdi-de.baw.de/icheArchiv
Thermodynamic limit of random partitions and dispersionless Toda hierarchy
We study the thermodynamic limit of random partition models for the instanton
sum of 4D and 5D supersymmetric U(1) gauge theories deformed by some physical
observables. The physical observables correspond to external potentials in the
statistical model. The partition function is reformulated in terms of the
density function of Maya diagrams. The thermodynamic limit is governed by a
limit shape of Young diagrams associated with dominant terms in the partition
function. The limit shape is characterized by a variational problem, which is
further converted to a scalar-valued Riemann-Hilbert problem. This
Riemann-Hilbert problem is solved with the aid of a complex curve, which may be
thought of as the Seiberg-Witten curve of the deformed U(1) gauge theory. This
solution of the Riemann-Hilbert problem is identified with a special solution
of the dispersionless Toda hierarchy that satisfies a pair of generalized
string equations. The generalized string equations for the 5D gauge theory are
shown to be related to hidden symmetries of the statistical model. The
prepotential and the Seiberg-Witten differential are also considered.Comment: latex2e using amsmath,amssymb,amsthm packages, 55 pages, no figure;
(v2) typos correcte
Effects of Fipronil on Non-target Ants and Other Invertebrates in a Program for Eradication of the Argentine Ant, Linepithema humile
Pesticides are frequently used to eradicate invasive ant species, but pose ecological harm. Previous studies assessed non-target effects only in terms of the increase or decrease of abundance or species richness after pesticide applications. Positive effects of the release from pressure caused by invasive ant species have not been considered so far. To more accurately assess pesticide effects in the field, the non-target effects of pesticides should be considered separately from the positive effects of such releases. Here, we used monitoring data of ants and other invertebrates collected in a program for the eradication of the Argentine ant, Linepithema humile (Mayr), using fipronil. First, we separately assessed the effects of L. humile abundance and fipronil exposure on non-target ants and other invertebrates using generalized linear models. The abundance of L. humile and the number of pesticide treatments were negatively associated with the total number of non-target individuals and taxonomic richness. We also noted negative relationships between the number of individuals of some ant species and other invertebrate taxonomic groups. The L. humile × pesticide interaction was significant, suggesting that the abundance of L. humile affected the level of impact of pesticide treatment on non-target fauna. Second, we evaluated the dynamics of non-target ant communities for 3 years using principal response curve analyses. Non-target ant communities treated with fipronil continuously for 3 years recovered little, whereas those treated for 1 year recovered to the level of the untreated and non-invaded environment
Formation of Plumes in Head-on Collisions of Galaxies
Using N-body and SPH modeling we perform 3D numerical simulations of head-on
collisions between gas rich disk galaxies, including collisions between
counter-rotating disks and off-center collisions. Pure stellar intruders do not
produce gaseous plumes similar to those seen in the Cartwheel and VII Zw466
complexes of interacting galaxies; the presence of gas in an intruder galaxy
and radiative cooling are important for the formation of a gaseous plume
extending from the disk of a target galaxy. A noticeable plume structure can be
formed if the mass of an intruder is a few percent of the mass of the primary.
The halo of the intruder is stripped in the collision, and dispersed
particles form a broad stellar bridge connecting the two galaxies. The fraction
of the intruder's halo dispersed in the collision depends on the total mass of
the intruder, and low-mass intruders lose most of their mass.Comment: 15 pages, 14 figures in GIF. To appear ApJ. Vol. 505 #
Cosmological Constraints from calibrated Yonetoku and Amati relation implies Fundamental plane of Gamma-ray bursts
We consider two empirical relations using data only from the prompt emission
of Gamma-Ray Bursts (GRBs), peak energy () - peak luminosity ()
relation (so called Yonetoku relation) and -isotropic energy () relation (so called Amati relation). We first suggest the independence
of the two relations although they have been considered similar and dependent.
From this viewpoint, we compare constraints on cosmological parameters,
and , from the Yonetoku and Amati relations
calibrated by low-redshift GRBs with . We found that they are
different in 1- level, although they are still consistent in 2-
level. This and the fact that both Amati and Yonetoku relations have systematic
errors larger than statistical errors suggest the existence of a hidden
parameter of GRBs. We introduce the luminosity time defined by as a hidden parameter to obtain a generalized Yonetoku
relation as . The new relation has much smaller systematic
error, 30%, and can be regarded as "Fundamental plane" of GRBs. We show a
possible radiation model for this new relation. Finally we apply the new
relation for high-redshift GRBs with to obtain
, which is consistent with the
concordance cosmological model within 2- level.Comment: 5 pages, 6 figures, published in JCA
On the Baryonic Branch Root of N=2 MQCD
We investigate the brane exchange in the framework of N=2 MQCD by using a
specific family of M fivebrane configurations relevant to describe the baryonic
branch root. An exchange of M fivebranes is realized in the Taub-NUT geometry
and controlled by the moduli parameter of the configurations. This family also
provides two different descriptions of the root. These descriptions are
examined carefully using the Taub-NUT geometry. It is shown that they have the
same baryonic branch and are shifted each other by the brane exchange.Comment: LaTeX, 25 pages, 7 figures, references adde
Hard to "tune in": neural mechanisms of live face-to-face interaction with high-functioning autistic spectrum disorder
Persons with autism spectrum disorders (ASD) are known to have difficulty in eye contact (EC). This may make it difficult for their partners during face to face communication with them. To elucidate the neural substrates of live inter-subject interaction of ASD patients and normal subjects, we conducted hyper-scanning functional MRI with 21 subjects with autistic spectrum disorder (ASD) paired with typically-developed (normal) subjects, and with 19 pairs of normal subjects as a control. Baseline EC was maintained while subjects performed real-time joint-attention task. The task-related effects were modeled out, and inter-individual correlation analysis was performed on the residual time-course data. ASD-Normal pairs were less accurate at detecting gaze direction than Normal-Normal pairs. Performance was impaired both in ASD subjects and in their normal partners. The left occipital pole (OP) activation by gaze processing was reduced in ASD subjects, suggesting that deterioration of eye-cue detection in ASD is related to impairment of early visual processing of gaze. On the other hand, their normal partners showed greater activity in the bilateral occipital cortex and the right prefrontal area, indicating a compensatory workload. Inter-brain coherence in the right IFG that was observed in the Normal-Normal pairs (Saito et al., 2010) during EC diminished in ASD-Normal pairs. Intra-brain functional connectivity between the right IFG and right superior temporal sulcus (STS) in normal subjects paired with ASD subjects was reduced compared with in Normal-Normal pairs. This functional connectivity was positively correlated with performance of the normal partners on the eye-cue detection. Considering the integrative role of the right STS in gaze processing, inter-subject synchronization during EC may be a prerequisite for eye cue detection by the normal partner
Hyperfine Anomaly of Be Isotopes and Anomalous Large Anomaly in Be
A new result of investigations of the hyperfine structure (hfs) anomaly in Be
isotopes is presented. The hfs constant for Be is obtained by using the
core plus neutron type wave function: . A large hfs anomaly of Be is found, which is mainly due
to a large radius of the halo single particle state.Comment: 14 pages, Late
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