526 research outputs found
Targeted disruption of the PD78 gene ( traF ) reduces pheromone-inducible conjugal transfer of the bacteriocin plasmid pPD1 in Enterococcus faecalis
Bacterial sex pheromone, cPD1, induces sexual aggregation of Enterococcus faecalis harboring the bacteriocin plasmid, pPD1, and enables pPD1 to transfer at high frequency in a liquid culture. PD78 is a cPD1-inducible cell surface protein encoded by pPD1. The PD78 gene, traF , was disrupted by homologous recombination between pPD1 and an artificial vector having a deletion in the middle portion of traF . The disruption of traF did not affect the cPD1-inducible aggregation but reduced the transfer frequency of pPD1 to 2% of the wild-type level.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/72850/1/j.1574-6968.1995.tb07537.x.pd
A Study of the Beginnings of New Confucianism
The publication of Eastern and Western cultures and their philosophies by Liang Shuming and the controversy over science and metaphysics which was instigated by Zhang Junmai are recognized as a Merkmal of the beginnings of the construction of the New Confucianist discourse. However, previous studies, especially in descriptions of the beginning of New Confucianism around the time of the May Fourth Movement or New Culture Movement, because of their lack of concern for the views of the Other, fail to deal comprehensively with both of the realities mentioned above. This paper describes the process of Zhang Junmai’s conversion from social science to philosophy by taking into account the socio-cultural context of that time, and shows that Hu Shi’s criticism of Henri Bergson and his philosophy of life brought about the rediscovery of New Confucianism from the perspective of the Other
Disentangling the migration phases during the non-breeding period reveals uneven carry-over effects to the subsequent breeding in a diving seabird
第6回極域科学シンポジウム[OB] 極域生物圏11月16日(月) 統計数理研究所 セミナー室1(D305
Intensity-modulated irradiation for superficial tumors by overlapping irradiation fields using intensity modulators in accelerator-based BNCT
The distribution of the thermal neutron flux has a significant impact on the treatment efficacy. We developed an irradiation method of overlapping irradiation fields using intensity modulators for the treatment of superficial tumors with the aim of expanding the indications for accelerator-based boron neutron capture therapy (BNCT). The shape of the intensity modulator was determined and Monte Carlo simulations were carried out to determine the uniformity of the resulting thermal neutron flux distribution. The intensity modulators were then fabricated and irradiation tests were conducted, which resulted in the formation of a uniform thermal neutron flux distribution. Finally, an evaluation of the tumor dose distribution showed that when two irradiation fields overlapped, the minimum tumor dose was 27.4 Gy-eq, which was higher than the tumor control dose of 20 Gy-eq. Furthermore, it was found that the uniformity of the treatment was improved 47% as compared to the treatment that uses a single irradiation field. This clearly demonstrates the effectiveness of this technique and the possibility of expanding the indications to superficially located tumors
Evaluation of Seismic Safety of a Large Caisson Structure
Some centrifugal shaking tests were carried out to clarify the mechanism of seismic interaction between a large caisson foundation and soil layers. Based on the test data, two-dimensional seismic effective stress FE analysis was applied, followed by verifying its applicability. Also, to clarify the flexural and shear behavior of the caisson structure members to the ultimate state and to evaluate the flexural and shear resistance, some large-scale model failure tests of poorly reinforced concrete in caisson foundation were carried out. Based on these test results above-mentioned, seismic analyses of an existing large caisson foundation to ground motion in level 2 earthquakes were carried out, adopting the above-mentioned analysis. As the results, it was concluded that the seismic safety on the caisson foundation was confirmed
Development of optimization method for uniform dose distribution on superficial tumor in an accelerator-based boron neutron capture therapy system
To treat superficial tumors using accelerator-based boron neutron capture therapy (ABBNCT), a technique was investigated, based on which, a single-neutron modulator was placed inside a collimator and was irradiated with thermal neutrons. In large tumors, the dose was reduced at their edges. The objective was to generate a uniform and therapeutic intensity dose distribution. In this study, we developed a method for optimizing the shape of the intensity modulator and irradiation time ratio to generate a uniform dose distribution to treat superficial tumors of various shapes. A computational tool was developed, which performed Monte Carlo simulations using 424 different source combinations. We determined the shape of the intensity modulator with the highest minimum tumor dose. The homogeneity index (HI), which evaluates uniformity, was also derived. To evaluate the efficacy of this method, the dose distribution of a tumor with a diameter of 100 mm and thickness of 10 mm was evaluated. Furthermore, irradiation experiments were conducted using an ABBNCT system. The thermal neutron flux distribution outcomes that have considerable impacts on the tumor’s dose confirmed a good agreement between experiments and calculations. Moreover, the minimum tumor dose and HI improved by 20 and 36%, respectively, compared with the irradiation case wherein a single-neutron modulator was used. The proposed method improves the minimum tumor volume and uniformity. The results demonstrate the method’s efficacy in ABBNCT for the treatment of superficial tumors
Genome-wide identification and annotation of HIF-1α binding sites in two cell lines using massively parallel sequencing
We identified 531 and 616 putative HIF-1α target sites by ChIP-Seq in the cancerous cell line DLD-1 and the non-cancerous cell line TIG-3, respectively. We also examined the positions and expression levels of transcriptional start sites (TSSs) in these cell lines using our TSS-Seq method. We observed that 121 and 48 genes in DLD-1 and TIG-3 cells, respectively, had HIF-1α binding sites in proximal regions of the previously reported TSSs that were up-regulated at the transcriptional level. In addition, 193 and 123 of the HIF-1α target sites, respectively, were located in proximal regions of previously uncharacterized TSSs, namely, TSSs of putative alternative promoters of protein-coding genes or promoters of putative non-protein-coding transcripts. The hypoxic response of DLD-1 cells was more significant than that of TIG-3 cells with respect to both the number of target sites and the degree of induced changes in transcript expression. The Nucleosome-Seq and ChIP-Seq analyses of histone modifications revealed that the chromatin formed an open structure in regions surrounding the HIF-1α binding sites, but this event occurred prior to the actual binding of HIF-1α. Different cellular histories may be encoded by chromatin structures and determine the activation of specific genes in response to hypoxic shock. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (doi:10.1007/s11568-011-9150-9) contains supplementary material, which is available to authorized users
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