Numerical Analysis to Examine the Effect of Landslides on Tunnels

In the vicinity of known landslide zones, tunnel routes should be designed such that the distance between the landslide and the tunnel is sufficient to avoid adverse impact of the landslide on the tunnel. This requires a good understanding of the effects of the landslide on the tunnel. We modeled the ground surrounding the tunnel and the landslide using numerical analysis to evaluate the quantitative effect of the tunnel offset from the landslide on ground stresses and displacement of the ground surface and tunnel crown. We considered the effects under different ground conditions and examined two different cases, when the landslide occurs before tunnel construction and where the landslide movement occurs after tunnel construction. We found that the required offset distance between the landslide and the tunnel depended on whether the landslide occurred before or after tunnel excavation and the characteristics of the site conditions, and the method of setting the offset distance needs to consider the conditions at each site. As a result, we conclude that under some conditions, the offset required by current technical standards may be inadequate and further investigation would be required

Centrifuge Model Tests of Tieback Anchors and Drainage Pipes for Stabilization of Slopes under Earthquake Loads

Tieback anchors are widely used for the stabilization of natural and manmade slopes in Japan. The interactions between tieback anchors and slopes under seismic loading need to be understood to develop rational design concepts and installation methods in earthquake prone areas. We conducted centrifuge model tests to examine the characteristics of dynamic and residual loads on tieback anchors installed in slopes subjected to seismic loads. If the model slope contained a saturated zone, circular failure occurred even with pre-tensioned tieback anchors, and the amplitude of the oscillating loads on the tieback anchors was very high. This suggested that excess pore water pressure may cause the design capacity of the anchors to be exceeded, depending on the stability of the slope and intensity of the earthquake. Additional tests were therefore conducted with model slopes with drainage pipes installed (perforated plastic tubes). The drainage pipes significantly reduced pore water pressure, which in turn enhanced the stability of the slope and reduced the loads on the tieback anchors. We conclude that installation of drainage pipes in earthfill slopes would enable the selection of smaller ground anchors and potentially reduce overall construction costs

Inverted ductal papilloma arising from the buccal minor salivary gland: A case report and immunohistochemical study

AbstractOral inverted ductal papilloma is a rare, benign epithelial tumor that exhibits an endophytic growth pattern and is found almost exclusively in the minor salivary glands. We report on a case of inverted ductal papilloma in the buccal mucosa. We also performed an immunohistochemical study. The tumor cells were positive for cytokeratin and epithelial membrane antigen, while negative for calponin, S-100 protein, α-SMA, vimentin, and desmin. This result indicated that the lesion arises from the excretory duct near the oral mucosal surface but not the myoepithelial cells. In addition, Ki-67 labeling index of 3.96% indicated the low level of proliferation

SBRT FOR CENTRAL LUNG TUMORS WITH 56 Gy/7 fr

Stereotactic body radiotherapy (SBRT) for centrally‑located lung tumors remains a challenge because of the increased risk of treatment‑related adverse events (AEs), and uncertainty around prescribing the optimal dose. The present study reported the results of central tumor SBRT with 56 Gy in 7 fractions (fr) at the University of Tokyo Hospital. A total of 35 cases that underwent SBRT with or without volumetric‑modulated arc therapy consisting of 56 Gy/7 fr for central lung lesions between 2010 and 2016 at the University of Tokyo Hospital were reveiwed. A central lesion was defined as a tumor within 2 cm of the proximal bronchial tree (RTOG 0236 definition) or within 2 cm in all directions of any critical mediastinal structure. Local control (LC), overall survival (OS), and AEs were investigated. The Kaplan‑Meier method was used to estimate LC and OS. AEs were scored per the Common Terminology Criteria for Adverse Events Version 4.0. Thirty‑five patients with 36 central lung lesions were included. Fifteen lesions were primary non‑small cell lung cancer (NSCLC), 13 were recurrences of NSCLC, and 8 had oligo‑recurrences from other primaries. Median tumor diameter was 29 mm. Eighteen patients had had prior surgery. At a median follow‑up of 13.1 months for all patients and 18.3 months in surviving patients, 22 patients had died, ten due to primary disease (4 NSCLC), while three were treatment‑related. The 1‑ and 2‑year OS were 57.3 and 40.4%, respectively, and median OS was 15.7 months. Local recurrence occurred in only two lesions. 1‑ and 2‑year LC rates were both 96%. Nine patients experienced grade ≥3 toxicity, representing 26% of the cohort. Two of these were grade 5, one pneumonitis and one hemoptysis. Considering the background of the subject, tumor control of our central SBRT is promising, especially in primary NSCLC. However, the safety of SBRT to central lung cancer remains controversial

Detection of DR antigen on leukemic cells from a patient suffering from adult T-cell leukemia and progressive systemic sclerosis.

This report concerns an unusual case of adult T cell leukemia (ATL) complicated with progressive systemic sclerosis (PSS). The surface markers of peripheral blood mononuclear cells (PBM) and lymph node cells, both of which mainly consisted of leukemic cells, were examined. The effect of these cells on the pokeweed mitogen (PWM)-induced IgG synthesis by normal PBM also was studied. The leukemic cells formed rosettes with sheep red blood cells (SRBC; E) and expressed T cell antigen, Leu-1, and DR antigen. The detection of cell surface antigens was carried out by employing monoclonal antibodies against these antigens. We diagnosed this case as DR positive ATL. In terms of the immunoregulatory function of these leukemic cells, the co-culture experiments showed that these cells had some suppressive effect on the PWM-induced IgG production by allogeneic normal PBM.</p

Overall Feature of CP dependence for Neutrino Oscillation Probability in Arbitrary Matter Profile

We study the CP dependence of neutrino oscillation probability for all channels in arbitrary matter profile within three generations. We show that an oscillation probability for \nu_e \to \nu_\mu can be written in the form P(\nu_e \to \nu_\mu) =A_{e\mu} cos \delta + B_{e\mu} sin \delta + C_{e\mu} without any approximation using the CP phase \delta. This result holds not only in constant matter but also in arbitrary matter. Another probability for \nu_\mu \to \nu_\tau can be written in the form P(\nu_\mu \to \nu_\tau)= A_{\mu\tau} cos \delta + B_{\mu\tau} sin \delta + C_{\mu\tau} + D_{\mu\tau} cos 2\delta + E_{\mu\tau} sin 2\delta. The term which is proportional to sin 2\delta disappear, namely E_{\mu\tau}=0, in symmetric matter. It means that the probability reduces to the same form as in constant matter. As for other channels, probabilities in arbitrary matter are at most the quadratic polynomials of sin \delta and cos \delta as in the above two channels. In symmetric matter, the oscillation probability for each channel reduces to the same form with respect to \delta as that in constant matter.Comment: 11 pages, no figures, LaTeX2e, a few misprints have been correcte

Enhancement of CP Violating terms for Neutrino Oscillation in Earth Matter

We investigate the $\nu_e \to \nu_{\mu}$ oscillation in the framework of three generations when neutrinos pass through the earth. The oscillation probability is represented by the form, $P(\nu_e \to \nu_\mu)=A\cos \delta+B\sin \delta+C$ in arbitrary matter profile by using the leptonic CP phase $\delta$. We compare our approximate formula in the previous paper with the formula which includes second order terms of $\alpha=\Delta m_{21}^2/\Delta m_{31}^2$ and $s_{13}=\sin \theta_{13}$. Non-perturbative effects of $\alpha$ and $s_{13}$ can be taken into account in our formula and the precision of the formula is rather improved around the MSW resonance region. Furthermore, we compare the earth matter effect of $A$ and $B$ with that of $C$ studied by other authors. We show that the magnitude of $A$ and $B$ can reach a few ten % of $C$ around the main three peaks of $C$ in the region $E>1$ GeV by numerical calculation. We give the qualitative understanding of this result by using our approximate formula. The mantle-core effect, which is different from the usual MSW effect, appears not only in $C$ but also in $A$ and $B$, although the effect is weakened.Comment: 16 pages, 5 figure