Drinfeld twist and symmetric Bethe vectors of the open XYZ chain with non-diagonal boundary terms

With the help of the Drinfeld twist or factorizing F-matrix for the eight-vertex solid-on-solid (SOS) model, we find that in the F-basis provided by the twist the two sets of pseudo-particle creation operators simultaneously take completely symmetric and polarization free form. This allows us to obtain the explicit and completely symmetric expressions of the two sets of Bethe states of the model.Comment: Latex file, 25 page

Laser gas-discharge absorption measurements of the ratio of two transition rates in argon

The ratio of two line strengths at 922.7 nm and 978.7 nm of argon is measured in an argon pulsed discharge with the use of a single-mode Ti:Sapphire laser. The result 3.29(0.13) is in agreement with our theoretical prediction 3.23 and with a less accurate ratio 2.89(0.43) from the NIST database.Comment: 5 pages, 2 figures, 1 tabl

Penta-quark states with hidden charm and beauty

More and more hadron states are found to be difficult to be accommodated by the quenched quark models which describe baryons as 3-quark states and mesons as antiquark-quark states. Dragging out an antiquark-quark pair from the gluon field in hadrons should be an important excitation mechanism for hadron spectroscopy. Our recent progress on the penta-quark states with hidden charm and beauty is reviewed.Comment: Plenary talk at the 5th Asia-Pacific Conference on Few-Body Problems in Physics 2011 (APFB2011), 22-26 Aug., 2011, Seoul, Kore

Biotic communities of freshwater marshes and mangroves in relation to saltwater incursions: implications for wetland regulation

An ecosystem-level study was conducted in the Guandu wetlands in subtropical coastal Taiwan to examine how salinity influences the abundance, diversity, and structure of biotic communities. We surveyed eight permanent study sites, spanning freshwater marshes, to the gate on the dyke, and mesohaline mangroves representing a gradient of the extent of saltwater incursions. Analyses of abiotic variables showed that salinity was the primary determining factor for discriminating habitat types in the wetlands, but communities differed in their sensitivity to salinity. The composition of plant and insect communities was most affected by the salinity gradient, suggesting the utility of these communities for ecological monitoring of saltwater incursions. However, spatial changes in communities at higher trophic levels, including macrobenthos, mollusks, fish, and birds, could not be explained simply by the salinity gradient. Instead, changes in these communities were more relevant to the composition of other biotic communities. Our results show that species richness and diversity of plant communities were higher in the marshes than in the mangroves. Nevertheless, insect communities censused in the mangroves had higher diversity, despite lower abundance and species richness. Macrobenthos surveyed in the mangroves showed higher biomass and number of taxa. Mollusks and fish were also more abundant at sites near the gate compared to the marsh sites. This suggests that maintaining a tidal flux by means of gate regulation is necessary for conserving the spatial heterogeneity and biodiversity of coastal wetlands

Iloprost improves running performance at 5,000 m in Han but not in Tibetans

Background: Tibetans lose less aerobic exercise capacity in hypoxia compared to lowland Han. We tested if inhalation of iloprost (to counter hypoxic pulmonary vasoconstriction) and furosemide (to decrease afferent vagal traffic from pulmonary receptors) improve performance in hypoxia in Han compared to Tibetans. Methods: 8 Tibetans and 8 Han, living at 2,260 m, did incremental uphill treadmill running to exhaustion at ambient pressure on day 1, followed by three runs at 5,000 m (hypobaric chamber) after inhalation of iloprost (ILO), furosemide (FUR) or placebo (PLA), on different days in a counter-balanced order. Results: In Han the performance decrement from 2,260 m to 5,000 m was greater than in Tibetans (p<0.05). In Han iloprost improved performance at 5,000 m compared to placebo (p<0.05 vs. PLA); furosemide had no effects. In Tibetans there were no treatment effects. Peripheral O2 saturations at peak exercise at 5,000 m, were higher by ~8 % in the Tibetans (p<0.05 vs. Han). Maximum heart rate was lowered by 13±6 bpm in Han at 5,000 m regardless of treatment compared to 2,260 m (p<0.05). Tibetans reached similar maximum heart rates ~200 bpm at 5,000 m and 2,260 m, independent of treatment. Conclusions: The blunting of the exercise impairment in severe hypoxia in Han during maximal exercise after inhalation of iloprost suggests that hypoxic pulmonary vasoconstriction and right ventricular function are potential performance limiting factors in Han in hypoxia

Respiratory Infections during SARS Outbreak, Hong Kong, 2003

The effect of community hygienic measures during the outbreak of severe acute respiratory syndrome in Hong Kong was studied by comparing the proportion of positive specimens of various respiratory viruses in 2003 with those from 1998 to 2002. Community hygienic measures significantly reduced the incidence of various respiratory viral infections

Atom trapping and two-dimensional Bose-Einstein condensates in field-induced adiabatic potentials

We discuss a method to create two-dimensional traps as well as atomic shell, or bubble, states for a Bose-Einstein condensate initially prepared in a conventional magnetic trap. The scheme relies on the use of time-dependent, radio frequency-induced adiabatic potentials. These are shown to form a versatile and robust tool to generate novel trapping potentials. Our shell states take the form of thin, highly stable matter-wave bubbles and can serve as stepping-stones to prepare atoms in highly-excited trap eigenstates or to study `collapse and revival phenomena'. Their creation requires gravitational effects to be compensated by applying additional optical dipole potentials. However, in our scheme gravitation can also be exploited to provide a route to two-dimensional atom trapping. We demonstrate the loading process for such a trap and examine experimental conditions under which a 2D condensate may be prepared.Comment: 16 pages, 10 figure

Genomic occupancy of Runx2 with global expression profiling identifies a novel dimension to control of osteoblastogenesis

BACKGROUND: Osteogenesis is a highly regulated developmental process and continues during the turnover and repair of mature bone. Runx2, the master regulator of osteoblastogenesis, directs a transcriptional program essential for bone formation through genetic and epigenetic mechanisms. While individual Runx2 gene targets have been identified, further insights into the broad spectrum of Runx2 functions required for osteogenesis are needed. RESULTS: By performing genome-wide characterization of Runx2 binding at the three major stages of osteoblast differentiation--proliferation, matrix deposition and mineralization--we identify Runx2-dependent regulatory networks driving bone formation. Using chromatin immunoprecipitation followed by high-throughput sequencing over the course of these stages, we identify approximately 80,000 significantly enriched regions of Runx2 binding throughout the mouse genome. These binding events exhibit distinct patterns during osteogenesis, and are associated with proximal promoters and also non-promoter regions: upstream, introns, exons, transcription termination site regions, and intergenic regions. These peaks were partitioned into clusters that are associated with genes in complex biological processes that support bone formation. Using Affymetrix expression profiling of differentiating osteoblasts depleted of Runx2, we identify novel Runx2 targets including Ezh2, a critical epigenetic regulator; Crabp2, a retinoic acid signaling component; Adamts4 and Tnfrsf19, two remodelers of the extracellular matrix. We demonstrate by luciferase assays that these novel biological targets are regulated by Runx2 occupancy at non-promoter regions. CONCLUSIONS: Our data establish that Runx2 interactions with chromatin across the genome reveal novel genes, pathways and transcriptional mechanisms that contribute to the regulation of osteoblastogenesis

Topological Charged Black Holes in High Dimensional Spacetimes and Their Formation from Gravitational Collapse of a Type II Fluid

Topological charged black holes coupled with a cosmological constant in $R^{2}\times X^{D-2}$ spacetimes are studied, where $X^{D-2}$ is an Einstein space of the form ${}^{(D-2)}R_{AB} = k(D-3) h_{AB}$. The global structure for the four-dimensional spacetimes with $k = 0$ is investigated systematically. The most general solutions that represent a Type $II$ fluid in such a high dimensional spacetime are found, and showed that topological charged black holes can be formed from the gravitational collapse of such a fluid. When the spacetime is (asymptotically) self-similar, the collapse always forms black holes for $k = 0, -1$, in contrast to the case $k = 1$, where it can form either balck holes or naked singularities.Comment: 14 figures, to appear in Phys. Rev.

LRRK2 A419V is not associated with Parkinson's disease in different Chinese populations

10.1371/journal.pone.0036123PLoS ONE77