642 research outputs found
Locality of vortex stretching for the 3D Euler equations
We consider the 3D incompressible Euler equations under the following
situation: small-scale vortex blob being stretched by a prescribed large-scale
stationary flow. More precisely, we clarify what kind of large-scale stationary
flows really stretch small-scale vortex blobs in alignment with the straining
direction. The key idea is constructing a Lagrangian coordinate so that the Lie
bracket is identically zero (c.f. the Frobenius theorem), and investigate the
locality of the pressure term by using it
p38 Mitogen-activated Protein Kinase Regulates Oscillation of Chick Pineal Circadian Clock
Extracellular signal-regulated kinase (ERK) and p38 are members of the mitogen-activated protein kinase (MAPK) family, and in some cases these kinases serve for closely related cellular functions within a cell. In a wide range of animal clock structures, ERK plays an important role in the circadian time-keeping mechanism. Here we found that immunoreactivity to p38 protein was uniformly distributed among cells in the chick pineal gland. On the other hand, a constant level of activated p38 was detected over the day, predominantly in the follicular and parafollicular pinealocytes that are potential circadian clock-containing cells. Chronic application of SB203580, a selective and reversible inhibitor of p38, to the cultured chick pineal cells markedly lengthened the period of the circadian rhythm of the melatonin release (up to 28.7 h). Noticeably, despite no significant temporal change of activated p38 level, a 4-h pulse treatment with SB203580 delayed the phase of the rhythm only when delivered during the subjective day. These results indicate a time-of-day-specific role of continuously activated p38 in the period length regulation of the chick pineal clock and suggest temporally separated regulation of the clock by two MAPKs, nighttime-activated ERK and daytime-working p38
Search for new physics via photon polarization of
We suggest a discriminant analysis of new physics beyond the standard model
through a detection of photon polarization in a radiative B meson decay. This
analysis is investigated in SUSY SU(5) GUT with right-handed neutrino and
left-right symmetric models. New physics search via CP asymmetry in the same
process are also evaluated in each model for comparison. We show that new
physics can be found via detecting the photon polarization in a parameter space
of TeV energy scale.Comment: 20 pages, 8 figures, v2:references added, v3:published versio
b tagging in ATLAS and CMS
Many physics signals presently studied at the high energy collision
experiments lead to final states with jets originating from heavy flavor
quarks. This report reviews the algorithms for heavy flavor jets identification
developed by the ATLAS and CMS Collaborations in view of the Run2 data taking
period at the Large Hadron Collider. The improvements of the algorithms used in
2015 and 2016 data analyses with respect to previous data taking periods are
discussed, as well as the ongoing developments in view of the next years of
data taking. The measurements of the performance of the algorithms on data as
well as the dedicated techniques for the identification of heavy flavor jets in
events with boosted topologies are also presented. Finally, the effectiveness
of heavy flavor jet identification in the complex environment expected during
the high luminosity LHC phase is discussed.Comment: 6 pages, Proceeding for the Fifth Annual Large Hadron Collider
Physics (LHCP2017) conferenc
CO2-rich komatiitic melt inclusions in Cr-spinels within beach sand from Gorgona Island, Colombia
Author Posting. © The Author(s), 2009. This is the author's version of the work. It is posted here by permission of Elsevier B.V. for personal use, not for redistribution. The definitive version was published in Earth and Planetary Science Letters 288 (2009): 33-43, doi:10.1016/j.epsl.2009.09.005.The volatile content of komatiite is a key to constrain the thermal and chemical evolution of the deep Earth. We report the volatile contents with major and trace element compositions of ~ 80 melt inclusions in chromian spinels (Cr-spinels) from beach sands on Gorgona Island, Colombia. Gorgona Island is a ~ 90 Ma volcanic island, where picrites and the youngest komatiites known on the Earth are present. Melt inclusions are classified into three types on the basis of their host Cr-spinel compositions: low Ti (P type), high Ti with high Cr# (K1 type) and high Ti with low Cr# (K2 type). Chemical variations of melt inclusions in the Cr-spinels cover all of the island's lava types. P-type inclusions mainly occur in the picrites, K1-type in high-TiO2 komatiites (some enriched basalts: E-basalts) and K2-type in low-TiO2 komatiites. The H2O and CO2 contents of melt inclusions within Cr-spinels from the beach sand are highly variable (H2O: 0.03–0.9 wt.%; CO2: 40–4000 ppm). Evaluation of volatile content is not entirely successful because of compositional alterations of the original melt by degassing, seawater/brine assimilation and post-entrapment modification of certain elements and volatiles. However, the occurrence of many melt inclusions with low H2O/K2O ratios indicates that H2O/K2O of Gorgona komatiite is not much different from that of modern mid-oceanic ridge basalt (MORB) or oceanic island basalt. Trend of CO2/Nb and Zr/Y ratios, accounted for by two-component mixing between the least degassed primary komatiite and low-CO2/Nb evolved basalt, allow us to estimate a primary CO2/Nb ratio of 4000 ± 2200 or a CO2 content of 0.16 ± 0.09 wt.%. The determined CO2/Nb ratio is unusually high, compared to that of MORB (530). Although the presence of CO2 in the Gorgona komatiite does not affect the magma generation temperature, CO2 degassing may have contributed to the eruption of high-density magmas. High CO2/Nb and the relatively anhydrous nature of Gorgona komatiite provide possible resolution to one aspect of the hydrous komatiite debate.This work is financially supported by grants from the Japan Society for the Promotion of Science
Influence of insulin injection on skin
Aims/Introduction: The influence of repeated insulin injection on subcutaneous tissue is known, but its impact on the skin is unclear. Therefore, this study aimed to elucidate the impact of repeated insulin injections on the skin.
Material and Methods: The properties of the skin and the subcutaneous tissue were evaluated in 52 insulin-treated adult patients with diabetes with abnormal findings at the site of self-injection (36 with subcutaneous nodules, 16 with suspected subcutaneous tissue induration) by ultrasonography. In all subjects, both normal and abnormal areas were examined. In addition, skin biopsies were performed in four subjects.
Results: The skin thickness of the normal and abnormal skin sites was 1.95 (1.60, 2.50) and 2.80 (2.27, 3.30) mm, respectively (median (first quartile, third quartile)), (P < 0.001). The biopsy specimens revealed slightly thickened and tight bundles of collagen in the dermis. Three patients had amyloid deposits in the subcutaneous tissue, and one also showed these in the dermis. These were positively stained for insulin antibody.
Conclusions: Repeated insulin injection procedures result in skin thickening. Increased collagen fibers and possibly amyloid deposition in the dermis may be involved. The results reaffirmed the importance of appropriate site rotation in insulin injection and revealed the usefulness of ultrasonographic skin examination in evaluating the self-injection procedure
Giant spin-driven ferroelectric polarization in TbMnO3 under high pressure.
The recent research on multiferroics has provided solid evidence that the breaking of inversion symmetry by spin order can induce ferroelectric polarization P. This type of multiferroics, called spin-driven ferroelectrics, often show a gigantic change in P on application of a magnetic field B. However, their polarization (~0.1 μC cm(-2)) is much smaller than that in conventional ferroelectrics (typically several to several tens of μC cm(-2)). Here we show that the application of external pressure to a representative spin-driven ferroelectric, TbMnO3, causes a flop of P and leads to the highest P (≈ 1.0 μC cm(-2)) among spin-driven ferroelectrics ever reported. We explain this behaviour in terms of a pressure-induced magnetoelectric phase transition, based on the results of density functional simulations. In the high-pressure phase, the application of B further enhances P over 1.8 μC cm(-2). This value is nearly an order of magnitude larger than those ever reported in spin-driven ferroelectrics
不安の社会学(1)
「不安の社会学」という本研究の目的は、現代社会において増加している不安の特徴を社会学的に明らかにすることである。また、これまでの不安についての社会学理論を再考し、さらにそれらの研究・整理を通して、現代におけるデュルケーム社会学の意義を検討することにある。 その序章にあたる本稿では、まず、フロイトを手がかりに、社会学的研究の対象としての「不安」について明らかにした。その上で、サムナーの「内集団/外集団」論を、フロイトの成長の初期段階における「外」への認識をふまえつつ、ギュルヴィッチの「われわれ意識」およびデュルケームの「社会統合論」によって拡充し、心理現象としての「不安」を社会学的に研究するための中範囲の理論を確立した
- …