Coreless and singular vortex lattices in rotating spinor Bose-Einstein condensates

We theoretically investigate vortex-lattice phases of rotating spinor Bose-Einstein condensates (BEC) with the ferromagnetic spin-interaction by numerically solving the Gross-Pitaevskii equation. The spinor BEC under slow rotation can sustain a rich variety of exotic vortices due to the multi-component order parameters, such as the Mermin-Ho and Anderson-Toulouse coreless vortices (the 2-dimensional skyrmion and meron) and the non-axisymmetric vortices with the sifting vortex cores. Here, we present the spin texture of various vortex-lattice states at higher rotation rates and in the presence of the external magnetic field. In addition, the vortex phase diagram is constructed in the plane by the total magnetization $M$ and the external rotation frequency $\Omega$ by comparing the free energies of possible vortices. It is shown that the vortex phase diagram in a $M$-$\Omega$ plane may be divided into two categories; (i) the coreless vortex lattice formed by the several types of Mermin-Ho vortices and (ii) the vortex lattice filling in the cores with the pure polar (antiferromagnetic) state. In particular, it is found that the type-(ii) state forms the composite lattices of coreless and polar-core vortices. The difference between the type-(i) and type-(ii) results from the existence of the singularity of the spin textures, which may be experimentally confirmed by the spin imaging within polarized light recently proposed by Carusotto and Mueller. We also discussed on the stability of triangular and square lattice states for rapidly rotating condensates.Comment: to be published in Phys. Rev.

Control of metastable states by heat flux in the Hamiltonian Potts model

The local equilibrium thermodynamics is a basic assumption of macroscopic descriptions of the out of equilibrium dynamics for Hamiltonian systems. We numerically analyze the Hamiltonian Potts model in two dimensions to study the violation of the assumption for phase coexistence in heat conduction. We observe that the temperature of the interface between ordered and disordered states deviates from the equilibrium transition temperature, indicating that metastable states at equilibrium are stabilized by the influence of a heat flux. We also find that the deviation is described by the formula proposed in an extended framework of the thermodynamics.Comment: 20 pages, 10 figure

SYNTHESIS OF 2,3,9,10-TETRAOXYGENATED BENZO[c]PHENANTHRIDINE DERIVATIVES VIA PALLADIUM-MEDIATED ARYL-ARYL COUPLING REACTION

Two 2,3,9,10-tetraoxygenated benzo[c]phenanthridine alkaloids, 1 2, originally reported as zanthoxyline and broussonpapyrine, respectively, were synthesized using the Pd-mediated intramolecular aryl-aryl coupling reaction as the key step

OsYSL16 plays a role in the allocation of iron

Graminaceous plants acquire iron by secreting mugineic acid family phytosiderophores into the rhizosphere and taking up complexes of iron and phytosiderophores through YSL (yellow stripe 1-like) transporters. Rice OsYSL15 is a transporter of the iron(III)-2′-deoxymugineic acid complex. OsYSL16 has 85 % similarity to both OsYSL15 and the iron(II)-nicotianamine transporter OsYSL2. In the present study, we show that OsYSL16 functionally complemented a yeast mutant defective in iron uptake when grown on medium containing iron(III)-deoxymugineic acid, but not when grown on medium containing iron(II)-nicotianamine. OsYSL16-knockdown seedlings were smaller than wild-type seedlings when only iron(III)chloride was supplied as an iron source. The iron concentration in shoots of OsYSL16-knockdown plants was similar to that of the wild type; however, they showed more severe chlorosis than wild-type plants under iron-deficient conditions. Furthermore, OsYSL16-knockdown plants accumulated more iron in the vascular bundles of the leaves. Expression of the OsYSL16 promoter fused to the β-glucuronidase gene showed that OsYSL16 is expressed in the root epidermis and vascular bundles of whole plants. The expression was typically observed around the xylem. In the vascular bundles of unelongated nodes, it was detected in the xylem of old leaves and the phloem of new leaves. Graminaceous plants translocate iron from the roots to old leaves mainly via the xylem and to new leaves mainly via the phloem. Our results suggest that OsYSL16 plays a role in the allocation of iron(III)-deoxymugineic acid via the vascular bundles. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (doi:10.1007/s11103-012-9930-1) contains supplementary material, which is available to authorized users

gamma 375W fibrinogen-synthesizing CHO cells indicate the accumulation of variant fibrinogen within endoplasmic reticulum

Background: Hepatic endoplasmic reticulum (ER) storage disease (HERSD) associated with hypofibrinogenemia has been reported in patients with four types of heterozygous gamma-chain variant fibrinogen in the C terminal region. Of interest, substitution of gamma R375W induced hypofibrinogenemia and HERSD, whereas gamma R375G induced dysfibrinogenemia. Objectives: To analyze the synthesis of variant fibrinogen and morphological characteristics, we established variant fibrinogen-producing cells and compared them with wild-type fibrinogen-synthesizing cells. Methods: The fibrinogen gamma-chain expression vectors coding gamma 375W and gamma 375G were altered by oligonucleotide-directed mutagenesis and transfected into Chinese hamster ovary (CHO) cells. Synthesis of fibrinogen (media and cell lysates) was measured by ELISA for each cloned cell line and morphological characteristics were observed by immunofluorescence and transmission electron microscopy. Results: The medium/cell lysate fibrinogen ratio of gamma 375W-CHO cells was markedly lower than that of the normal cells and gamma 375G-CHO cells. Immunostaining with anti-fibrinogen antibody showed only gamma 375W-CHO cells, but revealed two types of cells containing cytoplasmic inclusion bodies, scattered large-granular bodies and fibrous forms. Observation by confocal microscopy indicated that both inclusion bodies were colocalized with fibrinogen and ER-membrane protein; furthermore, transmission electron microscopic observation demonstrated dilatation of the ER by large-granular inclusion bodies and fibrous forms filled with regularly structured fibular materials within the dilated ER. Conclusion: These results demonstrated that assembled and non-secreted gamma 375W fibrinogen was accumulated in the dilated ER and aggregated variant fibrinogen was seen as regularly structured fibular materials, which was similar to the fingerprint-like pattern observed at inclusion bodies in patients' hepatocytes affected with HERSD.ArticleTHROMBOSIS RESEARCH. 133(1):101-107 (2014)journal articl

Elevation by Oxidative Stress and Aging of Hypothalamic-Pituitary-Adrenal Activity in Rats and Its Prevention by Vitamin E

The present study was conducted in order to determine whether oxidative stress during aging involves dysfunction of the hypothalamic-pituitary-adrenal (HPA) axis in association with the emergence of cognitive deficits. When young rats were subjected to oxidative stress in the form of hyperoxia, thiobarbituric acid reactive substances, conjugated diene and lipid hydroperoxides increased markedly in the HPA axis. Vitamin E inhibited such increases in lipid peroxides in each organ. Levels of corticotrophin-releasing hormone in the hypothalamus and plasma levels of adrenocorticotrophic hormone and corticosterone were markedly elevated in young rats exposed to hyperoxia. However, young rats fed vitamin E-supplemented diets showed no abnormal hormone secretion, even after being subjected to hyperoxia. Furthermore, glucocorticosteroid receptors (GR) in pyramidal cells in the Cornus ammonis 1 region of the hippocampus in young rats were markedly decreased by oxidative stress. Similar phenomena were also observed in normal aged rats and young rats fed vitamin E-deficient diet kept in a normal atmosphere. Vitamin E supplementation prevented the decrease in GR in the hippocampus and the increase in corticosterone secretion caused by hyperoxia. These results suggest that oxidative stress induces oxidative damage in the hippocampus and the HPA axis during aging, resulting in a cognitive deficit in rats, and that negative-feedback inhibition on HPA activity was markedly dampened due to an increase in corticosterone levels caused by loss of GR

VLBI Monitoring of 3C 84 (NGC 1275) in Early Phase of the 2005 Outburst

Multi-epoch Very Long Baseline Interferometry (VLBI) study of the sub-pc scale jet of 3C 84 is presented. We carried out 14-epoch VLBI observations during 2006-2009 with the Japanese VLBI Network (JVN) and the VLBI Exploration of Radio Astrometry (VERA), immediately following the radio outburst that began in 2005. We confirmed that the outburst was associated with the central ~1 pc core, accompanying the emergence of a new component. This is striking evidence of the recurrence of jet activity. The new component became brighter during 2008, in contrast to the constant gamma-ray emission that was observed with the Fermi Gamma-ray Space Telescope during the same time. We found that the projected speed of the new component is 0.23c from 2007/297 (2007 October 24) to 2009/114 (2009 April 24). The direction of movement of this component differs from that of the pre-existing component by ~40 degree. This is the first measurement of kinematics of a sub-pc jet in a gamma-ray active phase. Possible detection of jet deceleration and the jet kinematics in connection with the gamma-ray emission is discussed.Comment: 5 pages, 3 figures. Accepted for publication in PAS

Initial Pulmonary Respiration Causes Massive Diaphragm Damage and Hyper-CKemia in Duchenne Muscular Dystrophy Dog

The molecular mechanism of muscle degeneration in a lethal muscle disorder Duchene muscular dystrophy (DMD) has not been fully elucidated. The dystrophic dog, a model of DMD, shows a high mortality rate with a marked increase in serum creatine kinase (CK) levels in the neonatal period. By measuring serum CK levels in cord and venous blood, we found initial pulmonary respiration resulted in massive diaphragm damage in the neonates and thereby lead to the high serum CK levels. Furthermore, molecular biological techniques revealed that osteopontin was prominently upregulated in the dystrophic diaphragm prior to the respiration, and that immediate-early genes (c-fos and egr-1) and inflammation/immune response genes (IL-6, IL-8, COX-2, and selectin E) were distinctly overexpressed after the damage by the respiration. Hence, we segregated dystrophic phases at the molecular level before and after mechanical damage. These molecules could be biomarkers of muscle damage and potential targets in pharmaceutical therapies.ArticleSCIENTIFIC REPORTS. 3:2183 (2013)journal articl