Clusters of galaxies generally form by the gravitational merger of smaller clusters and groups. Major cluster mergers are the most energetic events in the Universe since the Big Bang. Some of the basic physical properties of mergers will be discussed, with an emphasis on simple analytic arguments rather than numerical simulations. Semi-analytic estimates of merger rates are reviewed, and a simp...

Five human clones containing genomic regions of polydA have been isolated by their ability to form intermolecular triple helices with agarose cross-linked polyU. All of these clones contain Alu repetitive DNA sequences. End-labelled DNA fragments containing these sequences have been successfully reconstituted onto nucleosome core particles by salt exchange. The structure of these has been exami...

Clusters of galaxies generally form by the gravitational merger of smaller clusters and groups. Major cluster mergers are the most energetic events in the Universe since the Big Bang. Some of the basic physical properties of mergers will be discussed, with an emphasis on simple analytic arguments rather than numerical simulations. Semi-analytic estimates of merger rates are reviewed, and a simp...

During the early phases of low-mass star formation, episodic accretion causes ejection high-velocity outflow bullets, which carry a fossil record driving protostar's history. We present 44 SPH simulations $1\,\mathrm{M}_{\odot}$ cores, covering wide range initial conditions, and follow cores for five free-fall times. Individual protostars are represented by sink particles, particles launch outf...

Abstract. During the pre-monsoon season, biomass burning (BB) activities are intensive in southern Asia. Facilitated by westerly circulation, those BB plumes can be transported to Tibetan Plateau (TP). Black carbon (BC), main aerosol species emissions, is an important climate warming agent, and its absorbing property strongly depends on size distribution mixing state. To elucidate influence of ...

NaGdF4 is regarded as an ideal upconversion (UC) host material for lanthanide (Ln(3+)) activators because of its unique crystal structure, high Ln(3+) solubility, low phonon energy and high photochemical stability, and Ln(3+)-doped NaGdF4 UC nanocrystals (NCs) have been widely investigated as bio-imaging and magnetic resonance imaging agents recently. To realize their practical applications, co...

An extraction system has been constructed that melts ice from the interior of ice cores and collects the resulting water aseptically. Using this system, bacteria entrapped in ice cores from different geographic locations, that range in age from 5 to 20,000 years old, have been isolated and characterized. Ice cores from the Guliya ice cap on the Tibetan Plateau (China) contained the highest numb...

We propose and demonstrate a novel approach to obtaining small-core polysilicon waveguides from the silicon fiber platform. The fibers were fabricated via a conventional drawing tower method and, subsequently, tapered down to achieve silicon core diameters of ∼1  μm, the smallest optical cores for this class of fiber to date. Characterization of the material properties have shown that the taper...

Filiform polyposis (FP) of the colon is an uncommon entity that is occasionally encountered in patients with inflammatory bowel disease (IBD). FP is morphologically characterized by multiple slender worm-like projections consisting of submucosal cores lined with normal mucosa. To date, only two cases of FP have been reported in patients with inflammatory conditions of the gastrointestinal tract...