1,440 research outputs found
Strong enhancement of chlorophyll a concentration by a weak typhoon
Recent studies demonstrate that chlorophyll a (chl a) concentrations in the
surface ocean can be significantly enhanced due to typhoons. The present study
investigated chl a concentrations in the middle of the South China Sea (SCS)
from 1997-2007. Only the Category1 (minimal) Typhoon Hagibis (2007) had a
notable effect on the chl a concentrations. Typhoon Hagibis had a strong
upwelling potential due to its location near the equator, and the forcing time
of the typhoon (>82 h) was much longer than the geostrophic adjustment time
(~63 h). The higher upwelling velocity and the longer forcing time increased
the depth of the mixed-layer, which consequently induced a strong phytoplankton
bloom that accounted for about 30% of the total annual chl a concentration in
the middle of the SCS. The implication is that the forcing time of a typhoon
should be long enough to establish a strong upwelling and consequently for the
induction of significant upper ocean responses.Comment: Typhoon-Ocean Environment interaction
Hawking radiation-quasinormal modes correspondence for large AdS black holes
It is well-known that the non-strictly thermal character of the Hawking
radiation spectrum generates a natural correspondence between Hawking radiation
and black hole quasinormal modes. This main issue has been analyzed in the
framework of Schwarzschild black holes, Kerr black holes and nonextremal
Reissner-Nordstrom black holes. In this paper, by introducing the effective
temperature, we reanalysis the non-strictly thermal character of large AdS
black holes. The results show that the effective mass corresponding to the
effective temperature is approximatively the average one in any dimension. And
the other effective quantities can also be obtained. Based on the known forms
of frequency in quasinormal modes, we reanalysis the asymptotic frequencies of
the large AdS black hole in three and five dimensions. Then we get the formulas
of the Bekenstein-Hawking entropy and the horizon's area quantization with
functions of the quantum "overtone" number .Comment: 6 page
Dirac-boson stars
In this paper, we construct \textit{Dirac-boson stars} (DBSs) model composed
of a scalar field and two Dirac fields. The scalar field and both Dirac fields
are in the ground state. We consider the solution families of the DBSs for the
synchronized frequency and the nonsynchronized frequency
cases, respectively. We find several different solutions
when the Dirac mass and scalar field frequency
are taken in some particular ranges. In contrast, no similar
case has been found in previous studies of multistate boson stars. Moreover, we
discuss the characteristics of each type of solution family of the DBSs and
present the relationship between the ADM mass of the DBSs and the
synchronized frequency or the nonsynchronized frequency
. Finally, we calculate the binding energy of the DBSs
and investigate the relationship of with the synchronized frequency
or the nonsynchronized frequency .Comment: 26 pages, 12 figure
Relationship between dioxin and steroid hormones in sera of Vietnamese men
13301甲第4208号博士(保健学)金沢大学博士論文要旨Abstract 以下に掲載:Biomarkers 19(3) pp.236-240 2014. informaheathcare. 共著者:Xian Liang Sun, Teruniko Kido, Rie Okamoto, Ho Dung Manh, Shoko Maruzeni, Muneko Nishijo, Hideaki Nakagawa, Seijiro Honma, Takeshi Nakano, Takumi Takasuga, Dang Duc Nhu, Nguyen Ngoc Hung, Le Ke So
Learning Invariant Visual Representations for Compositional Zero-Shot Learning
Compositional Zero-Shot Learning (CZSL) aims to recognize novel compositions
using knowledge learned from seen attribute-object compositions in the training
set. Previous works mainly project an image and a composition into a common
embedding space to measure their compatibility score. However, both attributes
and objects share the visual representations learned above, leading the model
to exploit spurious correlations and bias towards seen pairs. Instead, we
reconsider CZSL as an out-of-distribution generalization problem. If an object
is treated as a domain, we can learn object-invariant features to recognize the
attributes attached to any object reliably. Similarly, attribute-invariant
features can also be learned when recognizing the objects with attributes as
domains. Specifically, we propose an invariant feature learning framework to
align different domains at the representation and gradient levels to capture
the intrinsic characteristics associated with the tasks. Experiments on two
CZSL benchmarks demonstrate that the proposed method significantly outperforms
the previous state-of-the-art
Excited Dirac stars with higher azimuthal harmonic index
In this paper, we investigate the properties of the first excited state Dirac
stars (DSs) with higher azimuthal harmonic index (specifically, the azimuthal
harmonic indexes = , , ), as well as the relationship
between the ADM mass and angular momentum of Dirac stars with respect to
frequency. Moreover, We find that the ergospheres of DSs appear at lower spinor
field frequencies, and both the ergospheres and the distribution of the spinor
field functions are asymmetric about the equatorial plane. Furthermore, we
introduce the ground state scalar field and examine its impact on this system,
which is known as the multi-state Dirac-boson stars (DBSs) model. We show
various types of solution families for DBSs under both synchronized frequency
and nonsynchronized frequencies and find that similar to DSs, the
spinor field and the ergospheres of DBSs are also asymmetric about the
equatorial plane, but the ergospheres appear at higher spinor field
frequencies.Comment: 22 pages, 8 figure
Difference in Thermotolerance Between Green and Red Color Variants of the Japanese Sea Cucumber, Apostichopus japonicus Selenka: Hsp70 and Heat-Hardening Effect
We studied thermal tolerance limits, heat-hardening, and Hsp70 to elucidate the difference in thermotolerance between two color variants of the sea Cucumber Apostichopus japonicus. Green and Red variants Occupy different habitats and have different aestivation responses to high temperature in summer. In the absence of heat-hardening the variants showed no difference in the temperature at which 50% of the individuals died: Green 31.49 degrees C; Red, 31.39 degrees C. However. Green specimens acquired higher thermotolerance than Red after a prior Sublethal heat exposure. After 72 h of recovery from a heat-hardening treatment (30 degrees C for 2 h) the survival of Green variants was more than 50% and that of Red wits less than 5% when they were treated at 33 degrees C for 2 h. Levels of mRNA and protein for Hsp70 were significantly higher in Green than Red after the heat shock of 30 degrees C, and the stability of hsp70 mRNA of Green was significantly higher than that of Red. Our findings suggest that within the same species, different variants that have similar thermal limits in the absence of heat-hardening can acquire different thermotolerances after a prior sublethal heat shock. The difference in induced thermotolerance between Green and Red is closely related to the expression pattern of Hsp70, which was partly governed by the stability of hsp70 mRNA
Holistic numerical simulation of a quenching process on a real-size multifilamentary superconducting coil
Superconductors play a crucial role in the advancement of high-field
electromagnets. Unfortunately, their performance can be compromised by
thermomagnetic instabilities, wherein the interplay of rapid magnetic and slow
heat diffusion can result in catastrophic flux jumps eventually leading to
irreversible damage. This issue has long plagued high- NbSn wires at
the core of high-field magnets. In this study, we introduce a groundbreaking
large-scale GPU-optimized algorithm aimed at tackling the complex intertwined
effects of electromagnetism, heating, and strain acting concomitantly during
the quenching process of superconducting coils. We validate our model by
conducting comparisons with magnetization measurements obtained from short
multifilamentary NbSn wires and further experimental tests conducted on
solenoid coils while subject to ramping transport currents. Furthermore,
leveraging our developed numerical algorithm, we unveil the dynamic propagation
mechanisms underlying thermomagnetic instabilities (including flux jumps and
quenches) within the coils. Remarkably, our findings reveal that the velocity
field of flux jumps and quenches within the coil is correlated with the amount
of Joule heating experienced by each wire over a specific time interval, rather
than solely being dependent on instantaneous Joule heating or maximum
temperature. These insights have the potential to pave the way for optimizing
the design of next-generation superconducting magnets, thereby directly
influencing a wide array of technologically relevant and multidisciplinary
applications
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