Efficient Detectors for MIMO-OFDM Systems under Spatial Correlation Antenna Arrays

This work analyzes the performance of the implementable detectors for multiple-input-multiple-output (MIMO) orthogonal frequency division multiplexing (OFDM) technique under specific and realistic operation system condi- tions, including antenna correlation and array configuration. Time-domain channel model has been used to evaluate the system performance under realistic communication channel and system scenarios, including different channel correlation, modulation order and antenna arrays configurations. A bunch of MIMO-OFDM detectors were analyzed for the purpose of achieve high performance combined with high capacity systems and manageable computational complexity. Numerical Monte-Carlo simulations (MCS) demonstrate the channel selectivity effect, while the impact of the number of antennas, adoption of linear against heuristic-based detection schemes, and the spatial correlation effect under linear and planar antenna arrays are analyzed in the MIMO-OFDM context.Comment: 26 pgs, 16 figures and 5 table

Notes on acyclic orientations and the shelling lemma

AbstractIn this paper we study two lemmas on acyclic orientations and totally cyclic orientations of a graph, which can be derived from the shelling lemma in vector subspaces. We give simple graph theoretical proofs as well as a proof by the interpretations of the shelling lemma in the special setting of graphs. Furthermore, we present similar interpretations of closely related theorems in vector subspaces, which do not seem to admit simple graph theoretical proofs

The cytogenesis of ascitic pha­gocytes

Judging from our vital observation conducted mainly by tissue culture, it was firmly demonstrated that ascitic phagocytes are not histiocytes but they are the cells closely related to monocytes and that the sites of the genesis are the milky spots of the greater omentum. The milky spots are most possibly the remnants of the mesenchymal hematopoiesis of the embryonic stage.</p

軟組織による外耳道閉鎖症例での軟骨伝導

A hearing aid using cartilage conduction (CC) has been proposed as an alternative to bone conduction (BC) hearing aids. The transducer developed for this application is lightweight, requires a much smaller fixation force than a BC hearing aid, and is more convenient to use. CC can be of great benefit to patients with fibrotic aural atresia. Fibrotic tissue connected to the ossicles provides an additional pathway (termed fibrotic tissue pathway) for sound to reach the cochlea by means of CC. To address the function of fibrotic tissue pathway, BC and CC thresholds were measured in six ears with fibrotic aural atresia. The relationship between the CC thresholds and the results of computed tomography was investigated. In the ears with the presence of a fibrotic tissue pathway, the CC thresholds were lower than the BC thresholds at 0.5 and 1.0 kHz. At 2.0 kHz, no significant difference was observed between the BC and CC thresholds. The current findings suggest that sound in the low to middle frequency range is transmitted more efficiently by CC via a fibrotic tissue pathway than BC. The development of hearing devices using CC can contribute to rehabilitation, particularly in patients with fibrotic aural atresia.博士（医学）・甲621号・平成26年3月17

The Effect of Melting Condition on the Properties of High Chromium Ferritic Steels(Metallurgy)

The influence of melting atmosphere and impurity elements on the hot workability of Fe-30%Cr alloys and the effect of vacuum and Ca refining on the mechanical properties have been studied. The results obtained are as follows. The deformation resistance of zone refined heat with the lowest impurity content is from 23 to 13 kg/mm^2 in the temperature range of 850°to 1300℃. Increasing the interstitial elements such as C and N in the vacuum-melted heat raises the deformation resistance in any hot-working temperature. However, the contents of O up to 0.2%, S up to 0.1%, Mn up to 2%, Si and Al up to 0.5% have not any significant effect on the deformation resistance. The heats of more than 0.017%C reveal intercrystalline fracture from above 1200℃. The crack initiations due to the cluster of alumina or chromium oxide inclusion are also observed. It is ascertained that the globular type inclusions found in the vacuum and Ca refined heats consist mainly of calcium aluminate, and their tensile strengths are approximately 45 to 65 kg/mm^2 with elongations of 28 to 35% at room temperature -72°and -120℃, and the ductile fracture with a fine dimple pattern is observed

Potent and broad anticancer activities of leaf extracts from Melia azedarach L. of the subtropical Okinawa islands

Plant extracts have been traditionally used for various therapeutic applications. By conducting an initial screening of several subtropical plants, in this study, we evaluated the anticancer activities of Melia azedarach L. The extract from Melia azedarach L. leaves (MLE) show high cytotoxic effects on cancer cells and in vivo mouse and dog tumor models. During the initial screening, MLE showed strong antiproliferative activity against HT-29 colon, A549 lung, and MKN1 gastric cancer cells. In subsequent tests, using 39 human tumor cell lines, we confirmed the potent anticancer activities of MLE. The anticancer activity of MLE was also confirmed in vivo. MLE markedly inhibited the growth of transplanted gastric MKN1 cancer xenografts in mice. To elucidate the mechanism underlying the anticancer effects of MLE, MLE-treated MKN1 cells were observed using an electron microscope; MLE treatment induced autophagy. Furthermore, western blot analysis of proteins in lysates of MLE-treated cells revealed induction of light chain 3 (LC3)-II autophagosomal proteins. Thus, MLE appeared to suppress MKN1 cell proliferation by inducing autophagy. In addition, in the mouse macrophage cell line J774A.1, MLE treatment induced TNF-alpha production, which might play a role in tumor growth suppression in vivo. We also performed a preclinical evaluation of MLE treatment on dogs with various cancers in veterinary hospitals. Dogs with various types of cancers showed a mean recovery of 76% when treated with MLE. Finally, we tried to identify the active substances present in MLE. All the active fractions obtained by reverse-phase chromatography contained azedarachin B-related moieties, such as 3-deacetyl-12-hydroxy-amoorastatin, 12-hydroxy-amoorastatin, and 12-hydroxyamoorastaton. In conclusion, MLE contains substances with promising anticancer effects, suggesting their future use as safe and effective anticancer agents

ベタヒスチンが一側内耳破壊後のラットの前庭代償に与える影響

Background: Vestibular compensation (VC) after unilateral labyrinthectomy (UL) consists of the initial and late processes. These processes can be evaluated based on the decline in the frequency of spontaneous nystagmus (SN) and the number of MK801-induced Fos-positive neurons in the contralateral medial vestibular nucleus (contra-MVe) in rats. Histamine H3 receptors (H3R) are reported to be involved in the development of VC. Objective: We examined the effects of betahistine, an H3R antagonist, on the initial and late processes of VC in UL rats. Methods: Betahistine dihydrochloride was continuously administered to the UL rats at doses of 100 and 200 mg/kg/day using an osmotic minipump. MK801 (1.0 mg/kg) was intraperitoneally administered on days 7, 10, 12, and 14 after UL, while Fos-positive neurons were immunohistochemically stained in the contra-MVe. Results: The SN disappeared after 42 h, and continuous infusion of betahistine did not change the decline in the frequency of SN. The number of MK801-induced Fos-positive neurons in contra-MVe significantly decreased on days 7, 10, and 12 after UL in a dose-dependent manner in the betahistine-treated rats, more so than in the saline-treated rats. Conclusion: These findings suggest that betahistine facilitated the late, but not the initial, process of VC in UL rats

Zee Model Confronts SNO Data

We reexamine the solution of the minimal Zee model by comparing with the data of the SNO experiment, and conclude that the model is strongly disfavored but not yet excluded by the observations. Two extensions of the Zee model are briefly discussed both of which introduce additional freedom and can accommodate the data.Comment: 16 pages LaTeX including 7 figure

Repeated mitral valve replacement in a patient with extensive annular calcification

<p>Abstract</p> <p>Background</p> <p>Mitral valve replacement in the presence of severe annular calcification is a technical challenge.</p> <p>Case report</p> <p>A 47-year-old lady who had undergone mitral and aortic valve replacement for rheumatic disease 27 years before presented with dyspnea. At reoperation, extensive mitral annular calcification was hindering the disc motion of the Starr-Edwards mitral prosthesis. The old prosthesis was removed and a St Jude Medical mechanical valve was implanted after thorough annular debridement. Postoperatively the patient developed paravalvular leak and hemolytic anemia, subsequently undergoing reoperation three days later. The mitral valve was replaced with an Edwards MIRA valve, with a bulkier sewing cuff, after more aggressive annular debridement. Although initially there was no paravalvular leak, it recurred five days later. The patient also developed a small cerebral hemorrhage. As the paravalvular leak and hemolytic anemia gradually worsened, the patient underwent reoperation 14 days later. A Carpentier-Edwards bioprosthetic valve with equine pericardial patches, one to cover the debrided calcified annulus, another as a collar around the prosthesis, was used to eliminate paravalvular leak. At 7 years postoperatively the patient is doing well without any evidence of paravalvular leak or structural valve deterioration.</p> <p>Conclusion</p> <p>Mitral valve replacement using a bioprosthesis with equine pericardial patches was useful to overcome recurrent paravalvular leak due to severe mitral annular calcification.</p