232 research outputs found

    The Effect of Poloidal Magnetic Field on Type I Planetary Migration: Significance of Magnetic Resonance

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    We study the effect of poloidal magnetic field on type I planetary migration by linear perturbation analysis in the shearing-sheet approximation and the analytic results are compared with numerical calculations. In contrast to the unmagnetized case, the basic equations that describe the wake due to the planet in the disk allow magnetic resonances at which density perturbation diverges. In order to simplify the problem, we consider the case without magneto-rotational instability. We perform two sets of analyses: two-dimensional and three-dimensional. In two-dimensional analysis, we find the generalization of the torque formula previously known in unmagnetized case. In three-dimensional calculations, we focus on the disk with very strong magnetic field and derive a new analytic formula for the torque exerted on the planet. We find that when Alfven velocity is much larger than sound speed, two-dimensional torque is suppressed and three-dimensional modes dominate, in contrast to the unmagnetized case.Comment: 33 pages, 10 figures, typos corrected, discussion added, reference added, Accepted for publication in Ap

    Hepatic Branch Vagotomy Can Suppress Liver Regeneration in Partially Hepatectomized Rats

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    The role of the vagus nerve in liver regeneration after partial hepatectomy was studied by comparing the effects of hepatic branch vagotomy with those of hepatic branch sympathectomy in rats. The liver weight as a percentage of body weight decreased significantly 7 days after vagotomy compared with the controls and this was associated with a reduction in food intake. There was no difference in the liver weights between the control rats and the pair-fed vagotomized rats. Hepatic sympathectomy had no significant effect on the liver weight. The serum scores indicating hepatic function showed no difference between the control and the vagotomized rats except alkaline phosphatase. The concentration of insulin was unchanged. The number of mitotic hepatocytes remained high at 7 days after vagotomy: These observations led us to conclude that the vagus nerve stimulates liver regeneration, and its effect depends on vagal factors directly and specifically

    Relationship between Cariogenic Bacteria and pH of Dental Plaque at Margin of Fixed Prostheses

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    Objective. The purpose of this study was to investigate whether teeth that have undergone prosthetic restoration are under conditions that promote caries recurrence. Methods. The subjects were 20 dentate adults with both a healthy tooth and an affected tooth entirely covered with a complete cast crown in the molar regions of the same arch. The pH was measured in plaque adhering to the margin of the tooth covered with a complete cast crown and adhering to the cervicobuccal area of the natural tooth. In addition, the numbers of cariogenic bacteria (mutans streptococci and lactobacilli) were measured employing the saliva test. The relationships between the number of cariogenic bacteria and plaque pH of the natural tooth and between the number of cariogenic bacteria and plaque pH of the tooth covered with a complete cast crown were investigated. Results. The plaque pH of the tooth covered with a complete cast crown decreased as the numbers of SM and LB increased. The natural tooth were also influenced by the number of SM. Conclusion. Secondary caries are likely to develop from the marginal region of the crown in the oral cavity with a high caries risk unless a preventive program is prepared and the oral environment is improved following the program

    Clinical Study Relationship between Cariogenic Bacteria and pH of Dental Plaque at Margin of Fixed Prostheses

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    Objective. The purpose of this study was to investigate whether teeth that have undergone prosthetic restoration are under conditions that promote caries recurrence. Methods. The subjects were 20 dentate adults with both a healthy tooth and an affected tooth entirely covered with a complete cast crown in the molar regions of the same arch. The pH was measured in plaque adhering to the margin of the tooth covered with a complete cast crown and adhering to the cervicobuccal area of the natural tooth. In addition, the numbers of cariogenic bacteria (mutans streptococci and lactobacilli) were measured employing the saliva test. The relationships between the number of cariogenic bacteria and plaque pH of the natural tooth and between the number of cariogenic bacteria and plaque pH of the tooth covered with a complete cast crown were investigated. Results. The plaque pH of the tooth covered with a complete cast crown decreased as the numbers of SM and LB increased. The natural tooth were also influenced by the number of SM. Conclusion. Secondary caries are likely to develop from the marginal region of the crown in the oral cavity with a high caries risk unless a preventive program is prepared and the oral environment is improved following the program

    Proposal for measuring magnetism with patterned apertures

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    We propose a magnetic measurement method utilizing a patterned post-sample aperture in a transmission electron microscope. While utilizing electron magnetic circular dichroism, the method circumvents previous needs to shape the electron probe to an electron vortex beam or astigmatic beam. The method can be implemented in standard scanning transmission electron microscopes by replacing the spectrometer entrance aperture with a specially shaped aperture, hereafter called ventilator aperture. The proposed setup is expected to work across the whole range of beam sizes -- from wide parallel beams down to atomic resolution magnetic spectrum imaging.Comment: 6 pages, 4 figure

    Predicting the Start of the Aedes albopictus (Diptera: Culicidae) Female Adult Biting Season Using the Spring Temperature in Japan

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    Aedes albopictus (Skuse) (Diptera: Culicidae) is distributed widely and is common in much of Japan. In Japan, female adults begin to bite in between April and June, except in the southern subtropics where the mosquito has no dormant period. It is difficult to estimate the first Ae. albopictus biting day because it varies annually depending on the location. Over several years, we surveyed the mosquitoes at different locations that covered a range of warmer to cooler areas of Japan. We found an association between the timing of first biting day by Ae. albopictus and spring temperature. In spring months, the strongest correlation was found with mean April temperatures, followed by March. Based on these data, it may, therefore, be possible to apply a simple formula to predict the timing of the first biting day at various geographical locations in Japan. Forecasting maps were created using a simple prediction formula. We found that the first biting day for Ae. albopictus changed depending on early spring temperatures for each year. There was an approximate 20-d difference in first biting day between years with warmer and cooler springs. This prediction model will provide useful insight for planning and practice of Ae. albopictus control programs, targeting larvae and adults, in temperate regions globally.ArticleJournal of Medical Entomology.54(6):1519-1524(2017)journal articl

    Np95 is regulated by E1A during mitotic reactivation of terminally differentiated cells and is essential for S phase entry

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    Terminal differentiation exerts a remarkably tight control on cell proliferation. However, the oncogenic products of DNA tumor viruses, such as adenovirus E1A, can force postmitotic cells to proliferate, thus representing a powerful tool to study progression into S phase. In this study, we identified the gene encoding Np95, a murine nuclear phosphoprotein, as an early target of E1A-induced transcriptional events. In terminally differentiated (TD) cells, the activation of Np95 was specifically induced by E1A, but not by overexpression of E2F-1 or of the cyclin E (cycE)–cyclin-dependent kinase 2 (cdk2) complex. In addition, the concomitant expression of Np95 and of cycE–cdk2 was alone sufficient to induce S phase in TD cells. In NIH-3T3 cells, the expression of Np95 was tightly regulated during the cell cycle, and its functional ablation resulted in abrogation of DNA synthesis. Thus, expression of Np95 is essential for S phase entry. Previous evidence suggested that E1A, in addition to its well characterized effects on the pRb/E2F-1 pathway, activates a parallel and complementary pathway that is also required for the reentry in S phase of TD cells (Tiainen, M., D. Spitkousky, P. Jansen-Dürr, A. Sacchi, and M. Crescenzi. 1996. Mol. Cell. Biol. 16:5302–5312). From our results, Np95 appears to possess all the characteristics to represent the first molecular determinant identified in this pathway

    Repeated talaporfin sodium photodynamic therapy for esophageal cancer: safety and efficacy

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    [Background] Talaporfin sodium photodynamic therapy (tPDT) is an effective salvage treatment for local failure after chemoradiotherapy for esophageal cancer. Repeated tPDT could also be indicated for local recurrence or residue after the first salvage tPDT. However, the safety and efficacy of repeated tPDT have not been elucidated. [Methods] We reviewed 52 patients with esophageal cancer who were treated with the first tPDT at Kyoto University Hospital between October 2015 and April 2020. [Results] Among 52 patients, repeated tPDT after the first tPDT was indicated for 13 patients (25%), of which six had residual tumor, four had local recurrence after complete response (CR) after the first tPDT at the primary site, and six had metachronous lesion. The total session of repeated tPDT was 25; 16 were for primary sites and nine were for metachronous sites. Among them, six patients (46.2%) achieved local (L)-CR and nine lesions (56.3%) achieved lesion L-CR. By session, 10 sessions (40%) achieved L-CR. There were no severe adverse events except for one patient; this patient showed grade 3 esophageal stenosis and perforation after the third tPDT on the same lesion that was previously treated with porfimer sodium photodynamic therapy four times. [Conclusion] Repeated tPDT could be an effective and safe treatment for local failure even after salvage tPDT for esophageal cancer
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