468 research outputs found

    Atomic entanglement sudden death in a strongly driven cavity QED system

    Full text link
    We study the entanglement dynamics of strongly driven atoms off-resonantly coupled with cavity fields. We consider conditions characterized not only by the atom-field coupling but also by the atom-field detuning. By studying two different models within the framework of cavity QED, we show that the so-called atomic entanglement sudden death (ESD) always occurs if the atom-field coupling lager than the atom-field detuning, and is independent of the type of initial atomic state

    Follicular Oocytes Better Support Development in Rabbit Cloning Than Oviductal Oocytes

    Full text link
    This study was conducted to determine the effect of rabbit oocytes collected from ovaries or oviducts on the developmental potential of nuclear transplant embryos. Donor nuclei were obtained from adult skin fibroblasts, cumulus cells, and embryonic blastomeres. Rabbit oocytes were flushed from the oviducts (oviductal oocytes) or aspirated from the ovaries (follicular oocytes) of superovulated does at 10, 11, or 12-h post-hCG injection. The majority of collected oocytes were still attached to the sites of ovulation on the ovaries. We found that follicular oocytes had a significantly higher rate of fusion with nuclear donor cells than oviductal oocytes. There was no difference in the cleavage rate between follicular and oviductal groups, but morula and blastocyst development was significantly higher in the follicular group than in the oviductal group. Two live clones were produced in follicular group using blastomere and cumulus nuclear donors, whereas one live clone was produced in the oviductal group using a cumulus nuclear donor. These results demonstrate that cloned rabbit embryos derived from follicular oocytes have better developmental competence than those derived from oviductal oocytes.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/90481/1/cell-2E2011-2E0030.pd

    Spectroscopic Study of SU UMa-type Dwarf Nova YZ Cnc during its 2002 Superoutburst

    Full text link
    We report time-resolved spectroscopic observations of the SU Ursae Majoris dwarf nova, YZ Cnc, for 2 nights over 11 hrs during its 2002 January superoutburst. The spectra only show absorption-line profiles in the first day. But the lines display blue and red troughs, with ``W'' profiles in the second day. The radial velocity curve of the absorption troughs and emission peaks of HΞ²\beta has an amplitude of 49Β±1049\pm10 km sβˆ’1^{-1} and a phase offset of βˆ’0.07Β±0.04-0.07\pm0.04, which are very similar to those measured in quiescence; however, the Ξ³\gamma velocity deviates strongly from the systemic velocity measured in quiescence, showing variation of the order of Β±\pm60 km sβˆ’1^{-1}. And large shifts of ∼\sim70 km sβˆ’1^{-1} and ∼\sim0.09, for the orbital-averaged velocity and phase respectively, are also found in our observations. All these phenomena can be well explained with a precession of an eccentric disk and we conclude that these phenomena are the characteristic products of an eccentric accretion disk.Comment: 11 pages, 4 figures, accepted for publication in ChJA

    Ginseng and Ganoderma lucidum Use after Breast Cancer Diagnosis and Quality of Life: A Report from the Shanghai Breast Cancer Survival Study

    Get PDF
    Objective: To evaluate associations between quality of life (QOL) and use of ginseng and Ganoderma lucidum (G. lucidum) among breast cancer survivors. Methods: Included in this study were 4,149 women with breast cancer who participated in the Shanghai Breast Cancer Survival Study. Ginseng use was assessed at 6-, 18-, and 36-month post-diagnosis surveys; G. lucidum use was assessed at the 6- and 36-month surveys. QOL was evaluated at the 6- and 36-month surveys. Multiple linear regression models were used to examine associations between ginseng and G.lucidum use and QOL assessed at the 36-month survey, with adjustment for potential confounders and baseline QOL. Results: At 6 months post-diagnosis, 14.2 % of participants reported regular use of ginseng and 58.8 % reported use of G. lucidum. We found no significant associations between ginseng use at 6, 18, and 36 months post-diagnosis and participants’ total QOL score or individual scores for psychological, physical, or social well-being. Post-diagnosis G. lucidum use was positively associated with social well-being (adjusted mean difference: 1.26; 95 % CI: 0.66, 1.86), but was inversely associated with physical well-being (adjusted mean difference: 21.16; 95 % CI: 21.86, 20.47) with a dose-response pattern observed for cumulative number of times of use (P for trend,0.001 for both). Conclusion: We found no evidence that post-diagnosis ginseng use improved the QOL of breast cancer survivors. Post

    Do Ultrahigh Energy Cosmic Rays Come from Active Galactic Nuclei and Fermi Ξ³\gamma-ray Sources?

    Full text link
    We study possible correlations between ultrahigh energy cosmic rays (UHECRs), observed by Auger, AGASA and Yakutsk, and nearby active galactic nuclei (AGNs) and FermiFermi sources. We consider the deflection effects by a Galactic magnetic field (GMF) model constrained by the most updated measurements. We found that the average deflection angles of UHECRs by the Galactic magnetic fields are less than 4∘4^\circ. A correlation between the Auger cosmic-ray events and nearby AGNs with a significance level of ∼4Οƒ\sim 4\sigma was found for the Auger UHECR data sets with or without deflection correction. No correlation was found between the AGASA/Yakutsk events with nearby AGNs. Marginal correlations between the Auger events and the FermiFermi sources, and between AGASA events and FermiFermi AGNs were found when the deflections calculated by the GMF model were considered. However, no correlation was found between the Yakutsk data and FermiFermi sources. Some FermiFermi sources are close to the arrival directions of UHECR events detected by Auger, AGASA, and Yakutsk, most of which are probably chance coincidence rather than objects producing UHECRs in the nearby Universe. Four FermiFermi sources, NGC 4945, ESO 323-G77, NGC 6951, and Cen A, within 100~Mpc have UHECR events within 3.1∘3.1^{\circ} from their positions, which could potentially be cosmic ray accelerators. However, the association can only be confirmed if more UHECRs are preferably detected in these directions.Comment: 10 pages, 8 figures, 1 table. Published versio

    Broad-Spectrum Antiviral Activity of RNA Interference against Four Genotypes of Japanese Encephalitis Virus Based on Single MicroRNA Polycistrons

    Get PDF
    Japanese encephalitis virus (JEV), a neurotropic mosquito-borne flavivirus, causes acute viral encephalitis and neurologic disease with a high fatality rate in humans and a range of animals. Small interfering RNA (siRNA) is a powerful antiviral agent able to inhibit JEV replication. However, the high rate of genetic variability between JEV strains (of four confirmed genotypes, genotypes I, II, III and IV) hampers the broad-spectrum application of siRNAs, and mutations within the targeted sequences could facilitate JEV escape from RNA interference (RNAi)-mediated antiviral therapy. To improve the broad-spectrum application of siRNAs and prevent the generation of escape mutants, multiple siRNAs targeting conserved viral sequences need to be combined. In this study, using a siRNA expression vector based on the miR-155 backbone and promoted by RNA polymerase II, we initially identified nine siRNAs targeting highly conserved regions of seven JEV genes among strains of the four genotypes of JEV to effectively block the replication of the JEV vaccine strain SA14-14-2. Then, we constructed single microRNA-like polycistrons to simultaneously express these effective siRNAs under a single RNA polymerase II promoter. Finally, these single siRNAs or multiple siRNAs from the microRNA-like polycistrons showed effective anti-virus activity in genotype I and genotype III JEV wild type strains, which are the predominant genotypes of JEV in mainland China. The anti-JEV effect of these microRNA-like polycistrons was also predicted in other genotypes of JEV (genotypes II and IV), The inhibitory efficacy indicated that siRNAsΓ—9 could theoretically inhibit the replication of JEV genotypes II and IV

    Evolution of MicroRNA Genes in Oryza sativa and Arabidopsis thaliana: An Update of the Inverted Duplication Model

    Get PDF
    The origin and evolution of microRNA (miRNA) genes, which are of significance in tuning and buffering gene expressions in a number of critical cellular processes, have long attracted evolutionary biologists. However, genome-wide perspectives on their origins, potential mechanisms of their de novo generation and subsequent evolution remain largely unsolved in flowering plants. Here, genome-wide analyses of Oryza sativa and Arabidopsis thaliana revealed apparently divergent patterns of miRNA gene origins. A large proportion of miRNA genes in O. sativa were TE-related and MITE-related miRNAs in particular, whereas the fraction of these miRNA genes much decreased in A. thaliana. Our results show that the majority of TE-related and pseudogene-related miRNA genes have originated through inverted duplication instead of segmental or tandem duplication events. Based on the presented findings, we hypothesize and illustrate the four likely molecular mechanisms to de novo generate novel miRNA genes from TEs and pseudogenes. Our rice genome analysis demonstrates that non-MITEs and MITEs mediated inverted duplications have played different roles in de novo generating miRNA genes. It is confirmed that the previously proposed inverted duplication model may give explanations for non-MITEs mediated duplication events. However, many other miRNA genes, known from the earlier proposed model, were rather arisen from MITE transpositions into target genes to yield binding sites. We further investigated evolutionary processes spawned from de novo generated to maturely-formed miRNA genes and their regulatory systems. We found that miRNAs increase the tunability of some gene regulatory systems with low gene copy numbers. The results also suggest that gene balance effects may have largely contributed to the evolution of miRNA regulatory systems

    Motion Capture: From Radio Signals to Inertial Signals

    Full text link
    The study of the motion of individuals allows to gather relevant information on a person status, to be used in several fields (e.g., medical, sport, and entertainment). Over the past decade, the research activity in motion capture has benefited from the progress of portable and mobile sensors, paving the way toward the use of motion capture techniques in mHealth applications (e.g., remote monitoring of patients, and telerehabilitation). Indeed, even if the optical motion capture, which typically relies on a set of fixed cameras and body-worn reflecting markers, is generally perceived as the standard reference approach, other motion capture techniques, such as radio and inertial, are attracting an increasing attention because of their suitability in remote mHealth applications. Moreover, several hybrid approaches have been studied and proposed in order to overcome the limitations of component technologies considered independently. In this chapter, we present an overview of possible integration strategies between radio and inertial motion capture techniques. We start by investigating a radio-based approach, based on the fingerprinting radio localization technique. Then, the previous approach is improved by integrating inertial measurements: namely, accelerometers are used to provide an estimate of the nodes’ pitches. Finally, the radio signals are abandoned in favor of only inertial measurements (obtained through accelerometers, gyroscopes, and magnetometers). The advantages and limitations of all approaches are discussed in a comparative way, characterizing the similarities and differences between the various approaches

    C. elegans EIF-3.K Promotes Programmed Cell Death through CED-3 Caspase

    Get PDF
    Programmed cell death (apoptosis) is essential for the development and homeostasis of metazoans. The central step in the execution of programmed cell death is the activation of caspases. In C. elegans, the core cell death regulators EGL-1(a BH3 domain-containing protein), CED-9 (Bcl-2), and CED-4 (Apaf-1) act in an inhibitory cascade to activate the CED-3 caspase. Here we have identified an additional component eif-3.K (eukaryotic translation initiation factor 3 subunit k) that acts upstream of ced-3 to promote programmed cell death. The loss of eif-3.K reduced cell deaths in both somatic and germ cells, whereas the overexpression of eif-3.K resulted in a slight but significant increase in cell death. Using a cell-specific promoter, we show that eif-3.K promotes cell death in a cell-autonomous manner. In addition, the loss of eif-3.K significantly suppressed cell death-induced through the overexpression of ced-4, but not ced-3, indicating a distinct requirement for eif-3.K in apoptosis. Reciprocally, a loss of ced-3 suppressed cell death induced by the overexpression of eif-3.K. These results indicate that eif-3.K requires ced-3 to promote programmed cell death and that eif-3.K acts upstream of ced-3 to promote this process. The EIF-3.K protein is ubiquitously expressed in embryos and larvae and localizes to the cytoplasm. A structure-function analysis revealed that the 61 amino acid long WH domain of EIF-3.K, potentially involved in protein-DNA/RNA interactions, is both necessary and sufficient for the cell death-promoting activity of EIF-3.K. Because human eIF3k was able to partially substitute for C. elegans eif-3.K in the promotion of cell death, this WH domain-dependent EIF-3.K-mediated cell death process has potentially been conserved throughout evolution
    • …
    corecore