Unstable Periodic Orbits and Chaos(New Developments in Statistical Physics Similarities in Diversities,YITP Workshop)

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Evaluation of Eigenmodes of Dielectric Waveguides by a Numerical Method Based on the BPM

For weakly guiding dielectric waveguides, the eigenmode field distributions are calculated numerically with a simple algorithm. In this numerical method, the transverse sampling space can be chosen arbitrarily, and hence a narrow waveguide can be analyzed. The field satisfying scalar wave equation is expressed by the discrete Fourier transform and the mode eigenvalues and eigenfunctions are calculated by solving an eigenvalue equation numerically. The validity of this method is checked for 2-D waveguides having step and parabolic or square index distributions. It is found that for the well guided TE modes of the slab waveguide, the accuracy of this method is remarkably good, but some discrepancies are found if the mode is near cut off. In the problems where the normalized guide index b is small, caution should be taken in applying the results of this numerical method

Measurement and Modeling for the Mitigation of Organic Crystallization Fouling

One of the aromatic compound plants in Mitsubishi Chemical Corporation has a heavy crystallization fouling problem. In order to solve this problem, using a low power gamma ray sensor, we found the location of heaviest fouling and measured the fouling growth rate. We also made a crystallization fouling laboratory test unit (simulator) to study the effects of some factors, such as temperature, liquid velocity, surface roughness and liquid composition. Fouling rates of the industrial plant cooler and the laboratory fouling test unit were modeled using a combination of Kern-Seaton and Reitzer models. However, the parameters of the plant and test unit did not agree with each other, perhaps because of scale up problems. We also measured the melting process (removal) of the fouling with the test unit. The heat flux necessary to melt the foulant was measured and used for the actual plant melting system. In the industrial plant, a steam trace melting system was installed at the position of heaviest fouling, and the plant now runs better than before

Eicosapentaenoic Acid Intake Associated with Reduced Risk of Posttraumatic Stress Disorder after the Great East Japan Earthquake and Tsunami

Posttraumatic stress disorder (PTSD) is a debilitating condition characterized by intrusion, avoidance, hyperarousal symptoms after exposure to traumatic events. Since polyunsaturated fatty acids (PUFAs) have been implicated, we examined the possible association of PTSD with plasma PUFA level and dietary fish intake in 563 women who was struck by the Great East Japan Earthquake and Tsunami. The impact event scale-revised (IES-R) was used to assess PTSD symptoms. Dietary intake was estimated by a self-report questionnaire. Multivariate analysis controlling for age, body mass index, and stress revealed that PTSD status (IES-R ≥ 25) was associated with plasma eicosapentaenoic acid (EPA) level (P = 0.039). In the high-stress group, there were significantly inverse correlations of plasma EPA with IES-R total (r = −0.389, P = 0.031), intrusion (r = −0.370, P = 0.04), and hyperarousal scores (r = −0.480, P = 0.006), although such correlations were not found in the moderate-stress group. Fish intake that increased plasma EPA showed similar correlations with IES-R scores in the severely stressed group. Our results suggest that higher plasma EPA level and EPA-increasing fish intake are associated with a lower risk for PTSD in individuals who have suffered severe stress in a natural disaster

Preliminary Clinical Evaluation of Toxicity and Efficacy of A New Astaxanthin-rich Haematococcus pluvialis Extract

Astaxanthin (Ax), a carotenoid ubiquitously distributed in microorganisms, fish, and crustaceans, has been known to be a potent antioxidant and hence exhibit various physiological effects. We attempted in these studies to evaluate clinical toxicity and efficacy of long-term administration of a new Ax product, by measuring biochemical and hematological blood parameters and by analyzing brain function (using CogHealth and P300 measures). Ax-rich Haematococcus pluvialis extracts equivalent to 4, 8, 20 mg of Ax dialcohol were administered to 73, 38, and 16 healthy adult volunteers, respectively, once daily for 4 weeks to evaluate safety. Ten subjects with age-related forgetfulness received an extract equivalent to 12 mg in a daily dosing regimen for 12 weeks to evaluate efficacy. As a result, no abnormality was observed and efficacy for age-related decline in cognitive and psychomotor functions was suggested

Occurrence of silk stitch abscess after surgery in patients with oral squamous cell carcinoma

Objectives: To elucidate the predisposing factors and clinical characteristics related to the occurrence of stitch abscess after surgery in patients with oral squamous cell carcinoma (SCC). Patients and Methods: The subjects were 232 patients who underwent excision and/or reconstruction and/or neck dissection for oral SCC using silk sutures for high ligation of the blood vessels. Detection rates and characteristics of patients with stitch abscess were retrospectively evaluated by comparing patients with and without stitch abscesses after surgery diagnosed by ultrasonography and findings of various modalities in 232 patients. Several echogenic dots with subtle acoustic shadows in a hypoechoic mass were identified as the characteristic findings of stitch abscess on US. The patient groups with and without stitch abscess were compared with respect to various factors to identify those that predispose to the occurrence of stitch abscess. The factors analyzed included patients' sex and age, chemotherapy treatment, radiotherapy treatment, the presence of a history of allergy, and blood test results. Results: A significant correlation was found between the occurrence of stitch abscess and age, liver function abnormalities on blood tests, and the presence of a history of allergy. Multiple stitch abscesses clearly tended to occur more often than single ones in patients with stitch abscess. Conclusions: The occurrence of stitch abscesses was related to age, liver dysfunction, and/or the presence of allergies. When diagnosing stitch abscess, the occurrence of multiple stitch abscesses is important

Distribuição geográfica do período de incubação da ferrugem do cafeeiro em cenários de mudanças climáticas

The objective of this work was to simulate the geographical distribution of the incubation period of coffee leaf rust in Coffea arabica, using data of two regional climate models, Eta-HadGEM2-ES and Eta-MIROC5. The scenario of high greenhouse gas emission (RCP 8.5 W m-2) was used for the states of Minas Gerais and São Paulo, Brazil, for current and future climate scenarios. The behavior of six different regression equations for incubation period (IP), available in the literature, was also analyzed as affected by data from the regional climate models. The results indicate the possibility of an increase in the affected area in the studied region, when the IP is less than 19 days, from 0.5% for Eta-MIROC5 to 14.2% for Eta-HadGEM2-ES. The severity of coffee leaf rust in future scenarios should increase in the hottest and wettest months of the year, extending to the driest and coldest months. The potential of rust infection is estimated differently by the studied equations. In higher temperature scenarios, the Kushalappa & Martins equation indicates a very high severity potential.O objetivo deste trabalho foi simular a distribuição geográfica do período de incubação da ferrugem do cafeeiro Coffea arabica, com uso de dados de dois modelos climáticos regionais, o Eta-HadGEM2-ES e o Eta-MIROC5. O cenário de alta emissão de gases de efeito estufa (RCP 8,5 W m-2) foi utilizado para os estados de Minas Gerais e São Paulo, para os cenários climáticos atual e futuro. O comportamento de seis diferentes equações de regressão do período de incubação (PI), disponíveis na literatura, também foi analisado em função dos dados dos modelos climáticos regionais. Os resultados indicam possibilidade de aumento de área afetada na região estudada, com PI inferior a 19 dias, de 0,5% para Eta-MIROC5 a 14,2% para Eta-HadGEM2-ES. A severidade da ferrugem do cafeeiro em cenários futuros deverá aumentar nos meses mais quentes e úmidos do ano, estendendo-se para os meses mais secos e frios. O potencial de infecção da ferrugem é estimado de forma diferente pelas equações estudadas. Em cenários de temperaturas mais elevadas, a equação de Kushalappa & Martins indica um potencial muito alto de severidade

Alterations in 18F-FDG accumulation into neck-related muscles after neck dissection for patients with oral cancers

Background: 18 F-fluoro-2-deoxy-D-glucose ( 18 F-FDG) accumulations are commonly seen in the neck-related muscles of the surgical and non-surgical sides after surgery with neck dissection (ND) for oral cancers, which leads to radiologists having difficulty in diagnosing the lesions. To examine the alterations in 18 F-FDG accumulation in neck-related muscles of patients after ND for oral cancer. Material and Methods: 18 F-FDG accumulations on positron emission tomography (PET)-computed tomography (CT) in neck-related muscles were retrospectively analyzed after surgical dissection of cervical lymph nodes in oral cancers. Results: According to the extent of ND of cervical lymph nodes, the rate of patients with 18 F-FDG-PET-positive areas increased in the trapezius, sternocleidomastoid, and posterior neck muscles of the surgical and/or non-surgical sides. In addition, SUVmax of 18 F-FDG-PET-positive areas in the trapezius and sternocleidomastoid muscles were increased according to the extent of the ND. Conclusions: In evaluating 18 F-FDG accumulations after ND for oral cancers, we should pay attention to the 18 F-FDG distributions in neck-related muscles including the non-surgical side as false-positive finding

Brane gravity, higher derivative terms and non-locality

In brane world scenarios with a bulk scalar field between two branes it is known that 4-dimensional Einstein gravity is restored at low energies on either brane. By using a gauge-invariant gravitational and scalar perturbation formalism we extend the theory of weak gravity in the brane world scenarios to higher energies, or shorter distances. We argue that weak gravity on either brane is indistinguishable from 4-dimensional higher derivative gravity, provided that the inter-brane distance (radion) is stabilized, that the background bulk scalar field is changing near the branes and that the background bulk geometry near the branes is warped. This argument holds for a general conformal transformation to a frame in which matter on the branes is minimally coupled to the metric. In particular, Newton's constant and the coefficients of curvature-squared terms in the 4-dimensional effective action are determined up to an ambiguity of adding a Gauss-Bonnet topological term. In other words, we provide the brane-world realization of the so called $R^2$-model without utilizing a quantum theory. We discuss the appearance of composite spin-2 and spin-0 fields in addition to the graviton on the brane and point out a possibility that the spin-0 field may play the role of an effective inflaton to drive brane-world inflation. Finally, we conjecture that the sequence of higher derivative terms is an infinite series and, thus, indicates non-locality in the brane world scenarios.Comment: Latex, 18 pages; a comment on the spurious tensor mode was added; recovery condition of higher derivative gravity clarifie

Effect of Cetraxate, a Mucosal Protective Agent, on Gastric Mucosal Blood Flow and Gastric Clarithromycin Concentration in Nicotine-treated Rats

Our previous study demonstrated that combination treatment with cetraxate plus omeprazole, amoxicillin, and clarithromycin is effective for the eradication of Helicobacter pylon in smokers. To evaluate the effect of cetraxate on gastric mucosal blood flow (GMBF) and the gastric concentration of clarithromycin in nicotine-treated rats, 10 rats were divided into two groups given nicotine with or without cetraxate, and GMBF was measured by laser Doppler blood flowmetry. Another 36 rats were divided into three groups (control, nicotine, and nicotine + cetraxate). Clarithromycin was administered intraduodenally and nicotine was administered after 30 minutes, with cetraxate being given 30 minutes later. The gastric mucosal clarithromycin concentration was measured. After cetraxate administration, GMBF increased significantly in the nicotine + cetraxate group compared with the nicotine group (p<0.05). The mucosal clarithromycin concentration increased in the nicotine + cetraxate group compared with the nicotine group, but the difference was not significant. Our results indicate that cetraxate increased GMBF in nicotine-treated rats