1,054 research outputs found
Singular Vortex in Narrow Cylinders of Superfluid 3He-A Phase
Motivated by the on-going rotating cryostat experiments in ISSP, Univ. of
Tokyo, we explore the textures and vortices in superfluid 3He-A phase confined
in narrow cylinders, whose radii are R=50mum and 115mum. The calculations are
based on the Ginzburg-Landau (GL) framework, which fully takes into account the
orbital (l-vector) and spin (d-vector) degrees of freedom for chiral p-wave
pairing superfluid. The GL free energy functional is solved numerically by
using best known GL parameters appropriate for the actual experimental
situations at P=3.2MPa and H=21.6mT. We identify the ground state l-vector
configuration as radial disgyration (RD) texture with the polar core both at
rest and low rotations and associated d-vector textures for both narrow
cylinder systems under high magnetic fields. The RD which has a singularity at
center, changes into Mermin-Ho texture above the critical rotation speed which
is determined precisely, providing an experimental check for own proposal.Comment: 22 pages, 12 figure
Development of a novel DDS for site-specific PEGylated proteins
Because of the shifted focus in life science research from genome analyses to genetic and protein function analyses, we now know functions of numerous proteins. These analyses, including those of newly identified proteins, are expected to contribute to the identification of proteins of therapeutic value in various diseases. Consequently, pharmacoproteomic-based drug discovery and development of protein therapies attracted a great deal of attention in recent years. Clinical applications of most of these proteins are, however, limited because of their unexpectedly low therapeutic effects, resulting from the proteolytic degradation in vivo followed by rapid removal from the circulatory system. Therefore, frequent administration of excessively high dose of a protein is required to observe its therapeutic effect in vivo. This often results in impaired homeostasis in vivo and leads to severe adverse effects. To overcome these problems, we have devised a method for chemical modification of proteins with polyethylene glycol (PEGylation) and other water-soluble polymers. In addition, we have established a method for creating functional mutant proteins (muteins) with desired properties, and developed a site-specific polymer-conjugation method to further improve their therapeutic potency. In this review, we are introducing our original protein-drug innovation system mentioned above
The syncytium-specific expression of the Orysa;KRP3 CDK inhibitor: implication of its involvement in the cell cycle control in the rice (Oryza sativa L.) syncytial endosperm
During rice (Oryza sativa L.) seed development, the primary endosperm nucleus undergoes a series of divisions without cytokinesis, producing a multinucleate cell, known as a syncytium. After several rounds of rapid nuclear proliferation, the syncytium ceases to undergo mitosis; thereafter, the syncytium is partitioned into individual cells by a specific type of cytokinesis called cellularization. The transition between syncytium and cellularization is important in determining the final seed size and is a model for studying the cell cycle and cytokinesis. The involvement of cyclin-dependent kinase (CDK) inhibitors (CKIs) in cell cycle control was investigated here during the transition between syncytium and cellularization. It was found that one of the rice CKIs, Orysa;KRP3, is strongly expressed in the caryopsis at 2 d after flowering (DAF), and its expression is significantly reduced at 3 DAF. The other CKI transcripts did not show such a shift at 2 DAF. In situ hybridization analysis revealed that Orysa;KRP3 is expressed in multinucleate syncytial endosperm at 2 DAF, but not in cellularized endosperm at 3 DAF. Two-hybrid assays showed that Orysa;KRP3 binds Orysa;CDKA;1, Orysa;CDKA;2, Orysa;CycA1;1, and Orysa;CycD2;2. By contrast, Orysa;CDKB2;1 and Orysa;CycB2;2 do not show binding to Orysa;KRP3. Orysa;KRP3 was able to rescue yeast premature cell division due to the dominant positive expression of mutant rice CDKA;1 indicating that Orysa;KRP3 inhibited rice CDK. These data suggest that Orysa;KRP3 is involved in cell cycle control of syncytial endosperm
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
A prospective study of cumulative job stress in relation to mental health
BACKGROUND: This study tests associations between psychosocial stress at work measured by the effort-reward imbalance model in a dynamic perspective, and multiple indicators of poor mental health, in a prospective design. METHODS: 1986 male and female employees from four Belgian enterprises were followed-up over one year within the framework of the Somstress study. Based on two consecutive measurements, an index of cumulative job stress was constructed and its associations with five indicators of mental health were studied, excluding caseness at entry (for depression, anxiety, somatisation, chronic fatigue and psychotropic drug consumption respectively). Taking into account the longitudinal design, four categories of job stress are defined: 1) employees free from stress at both measures, 2) job stress present at first measure but not at the second one, 3) recent onset of job stress as evidenced by second measure 4) workers exposed to stress at both measures. Multivariate logistic regression with appropriate adjustments was applied. RESULTS: In bivariate analysis, a clear graded association of cumulative job stress with all five mental health indicators is observed, both in men and women. In multivariate logistic regression analysis, recent onset of stress is strongly associated with poor mental health among men (odds ratios ranging from 1.8 to 4.6), while cumulative stress shows strongest effects on mental health in women (odds ratios ranging from 1.4 to 7.1). CONCLUSION: Cumulative experience and recent onset of job stress in terms of high effort spent and low reward received is associated with elevated risk of all five indicators of poor mental health at follow-up in a large cohort of employees
Measurement and comparison of individual external doses of high-school students living in Japan, France, Poland and Belarus -- the "D-shuttle" project --
Twelve high schools in Japan (of which six are in Fukushima Prefecture), four
in France, eight in Poland and two in Belarus cooperated in the measurement and
comparison of individual external doses in 2014. In total 216 high-school
students and teachers participated in the study. Each participant wore an
electronic personal dosimeter "D-shuttle" for two weeks, and kept a journal of
his/her whereabouts and activities. The distributions of annual external doses
estimated for each region overlap with each other, demonstrating that the
personal external individual doses in locations where residence is currently
allowed in Fukushima Prefecture and in Belarus are well within the range of
estimated annual doses due to the background radiation level of other
regions/countries
Macro deformation and micro structure of 3D granular assemblies subjected to rotation of principal stress axes
This paper presents a numerical investigation on the behavior of three dimensional granular materials during continuous rotation of principal stress axes using the discrete element method. A dense specimen has been prepared as a representative element using the deposition method and subjected to stress rotation at different deviatoric stress levels. Significant plastic deformation has been observed despite that the principal stresses are kept constant. This contradicts the classical plasticity theory, but is in agreement with previous laboratory observations on sand and glass beads. Typical deformation characteristics, including volume contraction, deformation non-coaxiality, have been successfully reproduced. After a larger number of rotational cycles, the sample approaches the ultimate state with constant void ratio and follows a periodic strain path. The internal structure anisotropy has been quantified in terms of the contact-based fabric tensor. Rotation of principal stress axes densifies the packing, and leads to the increase in coordination numbers. A cyclic rotation in material anisotropy has been observed. The larger the stress ratio, the structure becomes more anisotropic. A larger fabric trajectory suggests more significant structure re-organization when rotating and explains the occurrence of more significant strain rate. The trajectory of the contact-normal based fabric is not centered in the origin, due to the anisotropy in particle orientation generated during sample generation which is persistent throughout the shearing process. The sample sheared at a lower intermediate principal stress ratio (b=0.0) (b=0.0) has been observed to approach a smaller strain trajectory as compared to the case b=0.5 b=0.5 , consistent with a smaller fabric trajectory and less significant structural re-organisation. It also experiences less volume contraction with the out-of plane strain component being dilative
Direct non-cyclooxygenase-2 targets of celecoxib and their potential relevance for cancer therapy
Celecoxib (Celebrex®) was developed as a selective cyclooxygenase-2 (COX-2) inhibitor for the treatment of chronic pain. However, it now appears that this compound harbours additional pharmacologic activities that are entirely independent of its COX-2-inhibitory activity. This review presents the recently emerged direct non-COX-2 targets of celecoxib and their proposed role in mediating this drug's antitumour effects
Flat bands in topological media
Topological media are systems whose properties are protected by topology and
thus are robust to deformations of the system. In topological insulators and
superconductors the bulk-surface and bulk-vortex correspondence gives rise to
the gapless Weyl, Dirac or Majorana fermions on the surface of the system and
inside vortex cores. Here we show that in gapless topological media, the
bulk-surface and bulk-vortex correspondence is more effective: it produces
topologically protected gapless fermions without dispersion -- the flat band.
Fermion zero modes forming the flat band are localized on the surface of
topological media with protected nodal lines and in the vortex core in systems
with topologically protected Fermi points (Weyl points). Flat band has an
extremely singular density of states, and we show that this property may give
rise in particular to surface superconductivity which could exist even at room
temperature.Comment: 9 pages, 5 figures, version to appear in JETP Letter
- …