216 research outputs found
Ground-state Competition of Two-Component Bosons in Optical Lattice near a Feshbach Resonance
We investigate the ground state properties of an equal mixture of two species
of bosons in its Mott-insulator phase at a filling factor two per site. We
identify one type of spin triplet-singlet transition through the competition of
ground state. When the on-site interaction is weak () the two particles
prefer to stay in the lowest band and with weak tunnelling between neighboring
sites the system is mapped into an effective spin-1 ferromagnetic exchange
Hamiltonian. When the interaction is tuned by a Feshbach resonance to be large
enough (), higher band will be populated. Due to the orbital coupling
term in the Hamiltonian, the two atoms in different orbits on a site
would form an on-site singlet. For a non-SU(2)-symmetric model, easy-axis or
easy-plane ferromagnetic spin exchange models may be realized corresponding to
phase separation or counter-flow superfluidity, respectively.Comment: Final version in PR
Mass Reconstruction of Galaxy-scale Strong Gravitational Lenses Using a Broken Power-law Model
With mock strong gravitational lensing images, we investigate the performance
of the broken power-law (BPL) model proposed by \citet{2020ApJ...892...62D} on
the mass reconstruction of galaxy-scale lenses. An end-to-end test is carried
out, including the creation of mock strong lensing images, the subtraction of
lens light, and the reconstruction of lensed images, where the lenses are
selected from the galaxies in the Illustris-1 simulation. We notice that,
regardless of the adopted mass models (the BPL model or its special cases), the
Einstein radius can be robustly determined from imaging data alone, and the
median bias is typically less than . Away from the Einstein radius, the
lens mass distribution tends to be harder to measure, especially at radii where
there are no lensed images detected. We find that, with rigid priors, the BPL
model can clearly outperform the single power-law models by achieving
median bias on the radial convergence profile within the Einstein radius. As
for the source light reconstructions, they are found to be sensitive to both
lens light contamination and lens mass models, where the BPL model with rigid
priors still performs best when there is no lens light contamination. We show
that, by correcting for the projection effect, the BPL model can estimate the
aperture and luminosity weighted line-of-sight velocity dispersions to an
accuracy of scatter. These results highlight the great potential of
the BPL model in strong lensing related studies.Comment: Accepted for publication in ApJ, 24 pages, 13 figures, 2 table
Galaxy-galaxy weak-lensing measurement from SDSS: II. host halo properties of galaxy groups
As the second paper of a series on studying galaxy-galaxy lensing signals
using the Sloan Digital Sky Survey Data Release 7 (SDSS DR7), we present our
measurement and modelling of the lensing signals around groups of galaxies. We
divide the groups into four halo mass bins, and measure the signals around four
different halo-center tracers: brightest central galaxy (BCG),
luminosity-weighted center, number-weighted center and X-ray peak position. For
X-ray and SDSS DR7 cross identified groups, we further split the groups into
low and high X-ray emission subsamples, both of which are assigned with two
halo-center tracers, BCGs and X-ray peak positions. The galaxy-galaxy lensing
signals show that BCGs, among the four candidates, are the best halo-center
tracers. We model the lensing signals using a combination of four
contributions: off-centered NFW host halo profile, sub-halo contribution,
stellar contribution, and projected 2-halo term. We sample the posterior of 5
parameters i.e., halo mass, concentration, off-centering distance, sub halo
mass, and fraction of subhalos via a MCMC package using the galaxy-galaxy
lensing signals. After taking into account the sampling effects (e.g. Eddington
bias), we found the best fit halo masses obtained from lensing signals are
quite consistent with those obtained in the group catalog based on an abundance
matching method, except in the lowest mass bin. Subject headings: (cosmology:)
gravitational lensing, galaxies: clusters: generalComment: 12 pages, 7 figures, submitted to Ap
BOAT: Basic Oligonucleotide Alignment Tool
<p>Abstract</p> <p>Background</p> <p>Next-generation DNA sequencing technologies generate tens of millions of sequencing reads in one run. These technologies are now widely used in biology research such as in genome-wide identification of polymorphisms, transcription factor binding sites, methylation states, and transcript expression profiles. Mapping the sequencing reads to reference genomes efficiently and effectively is one of the most critical analysis tasks. Although several tools have been developed, their performance suffers when both multiple substitutions and insertions/deletions (indels) occur together.</p> <p>Results</p> <p>We report a new algorithm, Basic Oligonucleotide Alignment Tool (BOAT) that can accurately and efficiently map sequencing reads back to the reference genome. BOAT can handle several substitutions and indels simultaneously, a useful feature for identifying SNPs and other genomic structural variations in functional genomic studies. For better handling of low-quality reads, BOAT supports a "3'-end Trimming Mode" to build local optimized alignment for sequencing reads, further improving sensitivity. BOAT calculates an E-value for each hit as a quality assessment and provides customizable post-mapping filters for further mapping quality control.</p> <p>Conclusion</p> <p>Evaluations on both real and simulation datasets suggest that BOAT is capable of mapping large volumes of short reads to reference sequences with better sensitivity and lower memory requirement than other currently existing algorithms. The source code and pre-compiled binary packages of BOAT are publicly available for download at <url>http://boat.cbi.pku.edu.cn</url> under GNU Public License (GPL). BOAT can be a useful new tool for functional genomics studies.</p
ESTROGEN ANCHORED NANOMICELLES FOR COMBINATIONAL DRUG DELIVERY WITH ENHANCED THERAPEUTIC EFFICACY: A PROTEOMICS GUIDED INVESTIGATION FOR MULTIFUNCTIONAL NANOTHERAPEUTICS
The employment of the stable isotope labeling with amino acids in cell culture (SILAC) based proteomic analysis as a guidance tool for investigation of cellular response of a multifunctional nanodelivery system has been described for cancer therapy. The multifunctional nanodelivery system in this study was based on an estrogen anchored multimodal nanomicelle (NPG). The key components of the multifunctional nanomicelle consist: β-cyclodextrin conjugated estrone (CDE1), an escort molecule; polymeric BH3 mimetic, a proapoptotic BcL-2 inhibitor; and the mitotic catastrophe agent paclitaxel. They were assembled into the nanomicelle by multiple weak interactions including hydrophobic/hydrophilic interaction and host-guest recognition. The resulting nanomicelle exhibited unimodal morphology with average size of 170 nm with sustained release. It was found that the nanoparticle exhibits excellent anti-tumor activities for the treatment of breast adenocarcinoma with exceptional targeting efficacy both in MCF-7 tumor bearing mice. NPG as a new drug delivery system demonstrated several merits such as the increased drug uptake in breast tumor tissue, low toxicity, potent tumor growth retardation and metastasis inhibition, as well as potential clinical practicality without compromising liver, kidney and immune function and ameliorating the conventional chemotherapeutics induced phlebitis in breast tumor bearing nude mice model. The systematic SILAC based proteomics study and the subsequent validation revealed that the synergistic induction of mitotic catastrophe through enhanced G2/M phase arrest and PI3K/Akt/mTOR mediated autophagy, account for the exceedingly potent anti-tumor activity of this convergent nanomicelle. Additionally, the verification of the top upregulated gene from the proteomics profiling revealed that the overexpression of zinc finger protein 350 (ZNF350/ZBRK1) is associated with the enhanced antitumor effect induced by NPG.KEYWORDS: Drug targeting, Estrogen Receptor, Proteomics, Paclitaxel, Gossypol, SynergismÂ
Integration of genome-wide identification, transcriptome and association analysis of HSP20 gene family to revealing genetic basis of floral organ number-related traits in tree peony
The HSP20 family is the major member of heat shock proteins that are essential components involved in plant growth, development, and stress response, but little is known about tree peony (Paeonia suffruticosa). In this study, genome-wide analysis combining HSP20 gene family expression analysis of tree peony transcriptome was conducted, and the association between SNPs of HSP20s and flower organ number-related traits was analyzed. A total of 149 members were identified in the P. ostii genome, and divided into 10 subfamilies, most of which were classified into cytoplasm or nucleus. Interestingly, their protein sequences were highly conserved, mainly containing motif 1 or 3. In addition, a total of 38 deferentially expressed HSP20s were identified from transcriptome of flower buds with 5-carpels and polycarpels of P. ostii plants at three developmental stages, among which PoHSP89 and PoHSP133 were further cloned from 271 cultivars for association analysis. It indicated that seven or 19 pairs of associated combinations were obtained with the number of carpel, petal, stamen in PoHSP89 and PoHSP133, which could explain the phenotypic variation by 1.79% to 4.06%, and 1.92% to 12.37%, respectively. It will provide a valuable basis for clarifying the phylogenetic relationship to understand their biological function within the HSP20 gene family, and the identified candidate genes and their corresponding associated SNP loci would reveal the genetic basis on floral organ number variation and be useful for molecular marker-assisted breeding of tree peony in view to improving ornamental traits and yields
LTe2 induces cell apoptosis in multiple myeloma by suppressing AKT phosphorylation at Thr308 and Ser473
Multiple myeloma (MM) is a highly heterogeneous hematological malignancy originating from B lymphocytes, with a high recurrence rate primarily due to drug resistance. 2-((1H-indol-3-yl)methyl)-3-((3-((1H-indol-3-yl)methyl)-1H-indol-2-yl)methyl)-1H-indole (LTe2), a tetrameric indole oligomer, possesses a wide range of anticancer activities through various mechanisms. Here, we aim to explore the anti-tumor efficiency and potential downstream targets of LTe2 in MM. Its bioactivity was assessed by employing MTT assays, flow cytometry, and the 5TMM3VT mouse model. Additionally, transcriptomic RNA-seq analysis and molecular dynamics (MD) experiments were conducted to elucidate the mechanism underlying LTe2 induced MM cell apoptosis. The results demonstrated that LTe2 significantly inhibited MM cell proliferation both in vitro and in vivo, and revealed that LTe2 exerts its effect by inhibiting the phosphorylation of AKT at the Thr308 and Ser473 sites. In summary, our findings highlight the potential of LTe2 as a novel candidate drug for MM treatment and provided a solid foundation for future clinical trials involving LTe2
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