171 research outputs found
Data Delivery Method Based on Neighbor Nodes’ Information in a Mobile Ad Hoc Network
This paper proposes a data delivery method based on neighbor nodes’ information to achieve reliable communication in a mobile ad hoc network (MANET). In a MANET, it is difficult to deliver data reliably due to instabilities in network topology and wireless network condition which result from node movement. To overcome such unstable communication, opportunistic routing and network coding schemes have lately attracted considerable attention. Although an existing method that employs such schemes, MAC-independent opportunistic routing and encoding (MORE), Chachulski et al. (2007), improves the efficiency of data delivery in an unstable wireless mesh network, it does not address node movement. To efficiently deliver data in a MANET, the method proposed in this paper thus first employs the same opportunistic routing and network coding used in MORE and also uses the location information and transmission probabilities of neighbor nodes to adapt to changeable network topology and wireless network condition. The simulation experiments showed that the proposed method can achieve efficient data delivery with low network load when the movement speed is relatively slow
Millimeter-Thick Single-Walled Carbon Nanotube Forests: Hidden Role of Catalyst Support
A parametric study of so-called "super growth" of single-walled carbon
nanotubes(SWNTs) was done by using combinatorial libraries of iron/aluminum
oxide catalysts. Millimeter-thick forests of nanotubes grew within 10 min, and
those grown by using catalysts with a thin Fe layer (about 0.5 nm) were SWNTs.
Although nanotube forests grew under a wide range of reaction conditions such
as gas composition and temperature, the window for SWNT was narrow. Fe
catalysts rapidly grew nanotubes only when supported on aluminum oxide.
Aluminum oxide, which is a well-known catalyst in hydrocarbon reforming, plays
an essential role in enhancing the nanotube growth rates.Comment: 11 pages, 3 figures. Jpn. J. Appl. Phys. (Express Letters) in pres
Calibration of Smartphone-Based Weather Measurements Using Pairwise Gossip
Accurate and reliable daily global weather reports are necessary for weather forecasting and climate analysis. However, the availability of these reports continues to decline due to the lack of economic support and policies in maintaining ground weather measurement systems from where these reports are obtained. Thus, to mitigate data scarcity, it is required to utilize weather information from existing sensors and built-in smartphone sensors. However, as smartphone usage often varies according to human activity, it is difficult to obtain accurate measurement data. In this paper, we present a heuristic-based pairwise gossip algorithm that will calibrate smartphone-based pressure sensors with respect to fixed weather stations as our referential ground truth. Based on actual measurements, we have verified that smartphone-based readings are unstable when observed during movement. Using our calibration algorithm on actual smartphone-based pressure readings, the updated values were significantly closer to the ground truth values
Hemodynamic ischemia of the anterior choroidal artery and reversal by carotid artery stenting 10 years after ipsilateral superficial temporal artery-middle cerebral artery bypass for symptomatic left middle cerebral artery stenosis
The pathogenesis of anterior choroidal artery (AChA) territory infarction includes various mechanisms, but hemodynamic causes are rare and difficult to diagnose. 77-year-old man, who had moderate left ICA stenosis and he had treated with STA-MCA bypass surgery for severe symptomatic left MCA stenosis 10 years earlier, was admitted with right hemiparesis and confused state. On admission, magnetic resonance imaging and angiography demonstrated patent bypass, but severe stenosis of left ICA with no opacification of the left AChA and A1 portion of the left ACA. Diffusionweighted imaging demonstrated ischemic lesion in the left corona radiata. Together with clinical findings, hemodynamic ischemia of the AChA region was suspected and left carotid artery stenting resulted in prompt improvement of symptoms. Hemodynamic ischemia of the AChA territory is rare, however, should be considered as a potential target of treatment when the ipsilateral ICA, A1 and M1 show stenoocclusive lesions
サンカ テツケイ ネンショウ ショクバイ ノ ディーゼル ハイキ ガス ショリ ギジュツ エノ オウヨウ
Iron oxides which were supported on three kinds of alumina (γ-Al2O3, χ-Al2O3 and
activated-Al2O3) were prepared for oxidation catalysts on an after-treatment system of diesel engine.
In methane oxidation experiment, we found that the hematite (α-Fe2O3), which was synthesized from
goethite (α-FeOOH), supported on χ-Al2O3 has the highest catalytic activity (over 70% in CH4
conversion) at 227K than the other catalysts. Also in the redox reaction between NOx and
activated-carbon as substitute for soot, the catalyst supported on χ-Al2O3 showed the highest
performance and CO gas was not observed in the products. It is concluded that in α-Fe2O3/χ-Al2O3
catalyst, α-Fe2O3 exists mainly on the surface of the support, because of flatness of the surface of
χ-Al2O3. On the other hand, in the case of α-Fe2O3/γ-Al2O3 catalyst, as the surface of support,
γ-Al2O3, is uneven, α-Fe2O3 do not partially exist on the surface but in the pores
Slope in preload recruitable stroke work relationship predicts survival after left ventriculoplasty and mitral repair in patients with idiopathic cardiomyopathy
AbstractBackgroundLeft ventriculoplasty (LVP) and mitral valve plasty (MVP) are sometimes effective for patients with idiopathic dilated cardiomyopathy (DCM) who are not eligible for heart transplantation. Strict patient selection is warranted for these controversial procedures.Methods and resultsThe subjects were 18 patients with idiopathic DCM and mitral regurgitation who had not been indicated for heart transplantation due to either older age or patient refusal, and who underwent LVP and MVP. Their mean age was 57±14 years and 50% were dependent on catecholamine infusion. The preload recruitable stroke work (PRSW) relationship and its slope (Mw) were estimated by a single-beat technique using transthoracic echocardiography. There were one 30-day mortality and six (33%) hospital deaths due to heart failure. The one-year survival rate was 50%. Left ventricular end-diastolic dimension (LVDd) decreased from 77±11 to 68±11mm (p=0.001) whereas the ejection fraction did not change. Preoperative Mw was significantly higher in one-year survivors than that in non-survivors (54±17ergcm−3103 vs. 31±10ergcm−3103, p=0.005). Preoperative LVDd was not different between the groups. The cut-off value of 42ergcm−3103 for Mw predicted one-year survival with high sensitivity (100%) and specificity (77%).ConclusionsMw, the slope in the PRSW relationship, may predict survival after LVP and MVP in patients with idiopathic DCM
Pathobiological implications of mucin (MUC) expression in the outcome of small bowel cancer.
Mucins have been associated with survival in various cancer patients, but there have been no studies of mucins in small bowel carcinoma (SBC). In this study, we investigated the relationships between mucin expression and clinicopathologic factors in 60 SBC cases, in which expression profiles of MUC1, MUC2, MUC3, MUC4, MUC5AC, MUC6 and MUC16 in cancer and normal tissues were examined by immunohistochemistry. MUC1, MUC5AC and MUC16 expression was increased in SBC lesions compared to the normal epithelium, and expression of these mucins was related to clinicopathologic factors, as follows: MUC1 [tumor location (p = 0.019), depth (p = 0.017) and curability (p = 0.007)], MUC5AC [tumor location (p = 0.063) and lymph node metastasis (p = 0.059)], and MUC16 [venous invasion (p = 0.016) and curability (p = 0.016)]. Analysis of 58 cases with survival data revealed five factors associated with a poor prognosis: poorly-differentiated or neuroendocrine histological type (
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