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Recent works investigating the grain growth inhibition mechanism by rapidly quenched VC-doped cemented carbides are reviewed. The rapid quenching enables to observe microscopic features at the sintering state of cemented carbide. The formation of (W,V)C x layers at WC/Co interfaces has already occurred during liquid phase sintering which control the grain growth rate. The structure and thickness of (W,V)C x layers are related to the lattice coherency between (W,V)C x and WC grains. The difference in the interface structure with different carbon content results in the difference of grain growth rate.

This paper describes the effect of micro surface texture on the lubrication conditions at the tool rake face in machining aluminum alloy. For this purpose, four types of micro surface texture were fabricated at the tool faces of cemented carbide through spattering, photolithography and wet etching, and the micro-textured tool faces were coated with diamond like carbon (DLC) or TiN. Then, orthogonal cutting experiments of aluminum alloy were conducted using the coated tools with and without micro-texture. The normal and friction forces and the coefficient of friction were obtained from the measured cutting forces. In addition, tool surface conditions were inspected with a CCD microscope after machining. As a result, it was found that parallel type and square-dot type of micro-textures improved effectively the lubrication conditions in machining aluminum alloy A6061-T6. It was also found that micro-texture was likely to improve the lubrication conditions more effectively as the pattern of texture became smaller and deeper.

We present a scheme using beta-barium borate (BBO) crystal to maximize fourth-harmonic ultraviolet (UV) generation from high-power, kHz-range repetition rate Nd lasers by reducing thermal dephasing during the phase matching process. Thermal dephasing due to nonlinear absorption (NLA) induced by two-photon absorption of high peak power fourth-harmonic UV radiation is reduced by minimizing second- and fourth-harmonic beam overlap through tight elliptical focusing perpendicular to the walk-off plane, leading to multi-watt, kHz-range repetition rate UV generation in BBO crystal. With such beam shaping, nearly 5 W at 10 kHz of 262-nm UV radiation is generated using an 8-mm long BBO crystal. The results of our investigation show an efficient way of achieving multi-watt UV generation at kHz-range repetition rate.

COMPSAC 2008, Turku Finland, 28 July - 1 Aug. 2008, During a software system development, existing similar systems are useful because such systems and their documents help developers to understand and reuse problems and solutions of the new system. Especially, such helps are effective if developers are not familiar with the new system. In this paper, we present a supporting tool called “So/M” for an analyst to define software requirements. By using So/M, the analyst can easily refer functions of existing similar systems, their commonality and the relationships among them. So/M also enables the analyst to choose the candidate of requirements, and to generate the skeleton of requirements. During a comparative experiment, we have confirmed that So/M significantly helped analysts unfamiliar with a system to be developed., Article, Proceedings of the 32th Annual International Computer Software and App lications Conference. 255-262 (2008)

Wear mechanism of the thermally transformed CVD α-Al2O3 that was produced from as-deposited κ-Al2O3 by different heat-treatment processes have been investigated. For alloy steel turning, the wear of the transformed α-Al2O3 produced by a heat-treatment through a cooling process after κ-Al2O3 deposition was uneven, that is, small chippings and flakings of the layer occurred on the wear surface, although its wear resistance was higher than that of as-deposited α-Al2O3 and as-deposited κ-Al2O3. On the other hand, the transformed α-Al2O3 produced by the heat-treatment without a cooling process but in connection to κ-Al2O3 deposition showed an excellent wear resistance without uneven wear. For the α-Al2O3 transformed without a cooling process, crack generation during the cooling is inhibited by the microcracks that have been generated before the cooling by a phase transformation of κ → α. Wear resistance is improved because the cooling cracks with a wide width, which will act as starting points of the uneven wear, decrease.

症例は74歳,女性.糖尿病と心房細動の既往あり. 2003年6月25日下腹部痛で内科を受診した.腹部CT上,小腸の著明な拡張を認めイレウスと診断され,イレウス管を挿入された. 2時間後,腹痛の急性増悪を認め外科へ紹介され,再度腹部CTを施行された.門脈ガス血症および上腸間膜動脈の閉塞が認められた.上腸間膜動脈閉塞症による汎発性腹膜炎と診断し緊急手術が施行された.小腸は全体に血流障害があり壊死した小腸を切除した. 2回目の腹部CTの約6時間後, 3回目のCTを行ったところ門脈ガスは消失していた.門脈ガス血症を伴う上腸間膜動脈閉塞症はきわめて予後不良であり,早期診断および手術が予後を規定する上で重要である.また,門脈ガス血症の経時的変化についての報告は稀であり文献的考察を含めて報告する.

今回,われわれは腹膜垂によりイレウスとなった症例を2例経験したので報告する。症例1は26歳,男性.腹痛を主訴に前医より紹介となった.イレウス,消化管穿孔,汎発性腹膜炎の診断で緊急手術を施行した. S状結腸腹膜垂が膀胱と癒着し索状物となっていた.この腹膜垂により小腸は絞扼され穿孔していた.穿孔小腸を切除した.症例2は67歳,女性.嘔吐,腹痛を主訴に来院し原因不明のイレウスによる汎発性腹膜炎の診断で緊急手術を施行した. S状結腸腹膜垂がS状結腸間膜に癒着しループ状の索状物となっており小腸が嵌入し壊死に陥っていた.壊死小腸を切除した. 2例ともに術後経過は良好であった.腹膜垂によるイレウスの報告は,本邦において自験例2例を含め12例であり,世界的にも33例である.若干の文献的考察を加えて報告する.

肝予備能評価法として我々が用いているtrimethadione (TMO) 負荷試験が, 肝硬変例における肝障害についての臨床的な重症度の評価に有効か否かを判定するために, Child-Pugh基準 (Pugh score) と対比して検討した.TMO経口投与4時間後のTMOと, その唯一の代謝物dimethadione (DMO) の血中濃度比 (DMO/TMO値) は, 臨床的な肝障害重症度を判定するPughscoreによる分類のA群0.33±0.07, B群0.26±0.10, C群0.11±0.06で, 各群間に有意差を認めた (p

To clarify whether ketamine suppresses both A-fiber-and C-fiber-mediated pain and to compare the effects of ketamine with those of MK-801.Experiments were performed on urethane/chloralose-anesthetized cats. Glass capillary microelectrodes were used to record extracellular single unit activities from wide dynamic range (WDR) neurons in the spinal dorsal horn. Responses evoked by electrical stimulation of the superficial peroneal (SP), posterior tibial (PT), or both nerves were analyzed. The responses to successive electrical stimuli were displayed on a personal computer using a raster-dot processing program.A subanesthetic dose of intravenous ketamine suppressed both A- and C-fiber responses of WDR neurons in a dose-dependent manner without affecting A-fiber response of low-threshold mechanoreceptive (LTM) neurons. The C-fiber response was more markedly suppressed than the A-fiber response. Intravenous administration of MK-801, a specificN-methyl-D-aspartate (NMDA) antagonist, selectively suppressed the C-fiber response of WDR neurons.Intravenous ketamine may suppress both A-and C-fiber-mediated pain at a subanesthetic dose. This finding could be a scientific basis for the usefulness of ketamine during clinical procedures such as dressing changes or débridement of the burned patient.

肝ミクロゾーム分画で代謝される抗てんかん薬のtrimethadione (TMO)を用いた負荷試験が,肝のいかなる組織形態学所見を反映しているか検討した.対象は肝硬変(LC) 16例,慢性肝炎(CH)と肝線維症の各2例の20例である.術前の肝CT像より算出した肝容積と肝組織の光学顕微鏡所見の画像解析により肝実質比(実質/実質+間質)や単位体積あたりの細胞数を求めた.それらの指標より肝実質量(肝容積×実質比),肝細胞量(肝容積×単位体積あたりの肝細胞数),肝実質細胞総量(肝容積×実質比×単位体積あたりの細胞数)を算出した.TMO負荷試験値と肝実質量や肝細胞量とは,それぞれ高い相関(r=0.771, r=0.809; p

It has been reported that caffeine (CA) metabolism in humans is catalyzed by cytochrome P450(CYP)1A2. Recently, we reported that human CYP3A4 and 2C, but not 1A2, contribute to trimethadione (TMO) N-demethylation in the human liver. In this study we simultaneously administered two indicators, CA (2 mg/kg) and TMO (4 mg/kg), which have different patterns of metabolism, to patients with cholelithiasis (control) or cirrhosis. The serum levels of CA and TMO, and their individual metabolites, were determined by high-performance liquid chromatography and gas chromatography, respectively. The metabolism of CA and TMO was significantly inhibited in patients with cirrhosis as compared with controls. The ratios of serum paraxanthine (PX)/CA and DMO/TMO at 4 h after administration of the two probe drugs were also significantly decreased in patients with cirrhosis. The PX/CA ratios of the smoking patients with cirrhosis were higher than those of non-smokers. No differences in serum DMO/TMO ratios were observed between the smokers and non-smokers. These results suggest that different estimations of hepatic oxidizing capacity, catalysed mainly by CYP2C and 3A4, are possible in humans.

肝硬変併存肝癌例の耐術評価に用いられている肝機能検査が, いかなる肝の形態的所見を反映しているか, 画像解析装置を用いて検討した. 肝硬変併存肝癌16例の肝実質の数か所から得た組織切片から単位体積あたりの肝細胞数と肝実質比を測定した. それにCT像から求めた肝容積とを組み合わせて肝細胞量や肝実質量および肝細胞総量を算出して形態的所見の定量化を試みた. さらに, これらの指標とICG負荷試験値 (ICGR15) や一般肝機能検査値とを比較検討した. ICGR15と, 実質比や単位体積あたりの細胞数および細胞量とは, r=-0.506 (p

Most industrial products are developed based on their former products including software. Revising existing software according to new requirements is thus an important issue. However, innovative techniques for software revision cannot be easily introduced to projects where software is not a central part. In this paper, we report how to explore and apply software engineering techniques to such non-ideal projects to encourage technology transfer to industry. We first show our experiences with industrial partners to explore which tasks could be supported in such projects and which techniques could be applied to such tasks. As a result, we found change impact analysis could be technically supported, and traceability techniques using information retrieval seemed to be suitable for it. We second had preliminary experiences of a method using such techniques with data in industry and evaluated them with our industrial partners. Based on the evaluation, we third improved such a method by using following techniques, indexing of technical documents for characterizing requirements changes, machine learning on source codes for validating predicted traceability and static source code analysis for finding indirect impacts. Our industrial partners finally evaluated the improved method, and they confirmed the improved method worked better than ever.

The trimethadione (TMO) tolerance test, an estimation based on serum dimethadione (DMO)/TMO ratio (DMO is the only metabolite of TMO) was used to quantitatively confirm the functional hepatic parenchyma after hepatectomy. Hepatic functional reserve was confirmed to be improved when measured by TMO tolerance test after transarterial embolization(TAE)for ruptured case of hepatocellular carcinoma. The patient well tolerated hepatectomy. Accordingly, activation of hepatic functional reserve with TAE was tried on 3 patients who were diagnosed inoperable because of decreased hepatic functional reserve. In these patients, DMO/TMO ratios also increased after TAE and were considered operable. Hepatectomies were carried out and all 3 patients well tolerated the surgery. Histological examination of resected hepatic specimens revealed the regenerative nests at the sites where TAE did not affected. TMO tolerance test was able to evaluate the improvement in hepatic functional reserve, based on the hepatic parenchyma lregeneration. Thus, this test can be applied to evaluate the hepatic functional reserve in cases with decreased hepatic functional reserve.

肝microsomeのcytochrome P450系のうち, 肝小葉中心性に局在する1A2で脱メチル化されるcareine (CA) を, 2mg/kg経口投与することで, 肝硬変32例, 対照として胆石症10例の肝機能を検討した. 健康成人男性5例の検討で, CAの血中濃度は, 経口投与後, 直線的に減少, 代謝産物は4～6時間で最高値となり, paraxanthine (PX) が優位であることより, CA投与後4時間の血清PX/CA値を代表値とした. このPX/CA値とCA clearance (CL) とは, r=0.852の有意 (p

肝虚血による肝ミクロソーム機能の変化を,トリメタジオン(TMO)負荷試験により調べた.TMO 4m/kgな急速静注し,血清中のTMOとTMOの代謝物であるジメタジオン(DMO)を測定した.無処置犬30頭におけるTMOの半減期は3.1±1.2時間,クリアランスは2.60±0.95ml/min/kgであった.TMO投与1時間後および2時間後の血清DMO/TMO比はそれぞれ0.63±0.27, 1.29±0.63で,どちらも半減期,クリアランスと有意(p

Thermal dephasing due to two-photon absorption-induced linear absorption is reduced by minimizing second- and fourth-harmonic beam overlap through tight elliptical focusing perpendicular to the walk-off plane, leading to multi-watt, high-repetition rate ultraviolet generation in BBO.

肝細胞癌手術の術前と術後に, リピオドール-抗癌剤懸濁液動注療法 (L-TAI) をおこなった, 絶対的非治癒切除例を除く肝切除耐術例34例の予後規定因子を検討した.そのうち11例 (32%) に再発を認めた.その無再発生存率は, 1年, 91%, 3年, 68%, 5年, 45%であった.L-TAIによる80%以上の腫瘍内壊死, 腫瘍径5cm以下, 組織学的被膜浸潤なし (fc-inf (-)) そして組織学的門脈侵襲なし (vp (-)) などの各因子は, 有意に予後に良い影響を与えた.被膜浸潤の有無にかかわらず, 3cm以下の腫瘍の5年無再発生存率は100%であった, さらにfc-inf (-) 例やfc-inf (+) 例のそれぞれにおいて, 壊死率の高いほど, また腫瘍径が小さいほど, 再発までの期間は延長した.

In a system development, the knowledge of a target business is very important factor for the success of a development. The needed part of such knowledge is different for each stakeholder. Therefore, we need a method to measure the level of understanding of a stakeholder and a method to categorize business knowledge. This paper proposes the metric of difficulty level in order to measure the business knowledge. Moreover, we performed the experiment to confirm the suitability of the proposed metric.

It is difficult to identify whether quality requirements are defined adequately or not, but there are few methods to support this kind of requirements analysis. In this paper, we propose a method based on software quality spectrum, that shows a ratio of quality characteristics embedded in a software engineering artifact, such as a requirements specification, a manual and so on. We assume similar kinds of software systems have similar spectrum, thus we can identify the adequacy of quality requirements for a new system by using spectrum of already existing similar systems. We confirmed the assumption above by analyzing actual software systems, i.e., web browsers and drawing tools.

Phosphorothioate oligonucleotide–peptide conjugates were synthesized by solid phase fragment condensation (SPFC). Arginine rich peptides could be successfully conjugated in 2.8–13.4% isolated yields. All the products were fully characterized by reversed phase HPLC and MALDI–TOF–MS to give satisfactory results.

QSIC 2005, Melbourne, Australia, Sep. 2005, Software in a specific domain has several characteristics and each characteristic should be fixed when the software requirements are specified. In addition, these characteristics sometimes correlate with each other. However, we sometimes forget to specify several characteristics and/or to take their correlations into account during requirements elicitation. In this paper, we propose a meta-model for representing such characteristics and their correlations, and also propose a method to build a model for a specific domain by using documents about existing software systems. By using our model for a domain, a requirements specification for a system in the domain could be complete and unambiguous because requirements analysts can check the characteristics that should be decided. The specification could be also correct and consistent because the analysts can know side effects of a requirement change by using correlation among the characteristics. We have applied our methods to a case study for confirming the usefulness of such model and the methods., Article, Proceedings : the Fifth International Conference on Quality Software. 215-222 (2005)

Article, IEICE TRANSACTIONS ON INFORMATION AND SYSTEMS. E91D(4): 897-906(2008)

An electrostatic force microscope system in a scanning electron microscope specimen chamber was developed to measure the surface potential of an insulator film on a conductive substrate irradiated by an electron beam. As the accelerating voltage varies with the constant beam current, the surface charges positively if the voltage is lower than 1 kV or higher than 3 kV but negatively if the voltage is between 1.1 and 2.7 kV. This positive-negative-positive potential alternation is explained by the relationship between the electron range and the film thickness, and verified by the Monte Carlo simulation of electron trajectories. By selecting the acceleration voltage as 30 kV to show less potential variation with time, the spatial potential distribution at the specimen surface is obtained, and a negative dip is observed around 50 μm from the edge of the irradiated area. The authors find that the depth of the dip increases with an increase in the electron dose, and the negative potential distribution spreads over 300 μm is obtained, which is almost 10 times larger than the primary electron range in the specimen. The characteristic variation in the distribution agrees with a hypothetically derived charge distribution obtained in a different experiment.

Pre-operative evaluation of the quantity of functional remnant hepatic parenchyma after hepatectomy was carried out to predict the optimal amount of hepatic resection using the trimethadione (TMO) tolerance test. This test is an estimate based on serum diamethadione (DMO)/TMO ratio (DMO is the only metabolite of TMO) 4 h after oral administration of TMO, and computed tomography (CT) scans of the liver in patients with hepatocellular carcinoma (HCC). The percentage of remnant hepatic parenchyma was calculated pre-operatively from the remaining non-cancerous portion and the whole hepatic parenchyma, excluding the HCC portion, using the CT scans. Presumptive remnant DMO/TMO ratio was calculated by multiplying the percentage of remnant hepatic parenchyma and pre-operative serum DMO/TMO ratio in 45 patients with HCC undergoing resection. The presumptive remnant DMO/TMO ratios were 0.31 +/- 0.10 (mean +/- s.d.) in 42 patients who survived hepatectomy and 0.13 +/- 0.02 (below 0.15) in the three patients who died from postoperative hepatic failure. Of these surviving patients, two patients who had the presumptive remnant DMO/TMO ratios under 0.15 developed postoperative severe complications. Thus, hepatectomy may not be indicated in patients where presumptive remnant DMO/TMO ratio is 0.15 and lower. These findings suggest that pre-operative measurement of presumptive remnant DMO/TMO ratio, when obtained with the CT of the liver and TMO tolerance test, is useful for prediction of the quantity of functional remnant hepatic parenchyma after hepatectomy in patients with chronic liver disease.

Pharmacokinetic interactions between caffeine 2 mg/kg and trimethadione 4 mg/kg were evaluated in 10 healthy volunteers. Whether administered alone or together, the total body clearance (CL), the apparent volume of distribution (Vd) and half-life (t1/2) of caffeine and trimethadione were the same, however, there was a weak correlation between the CL of caffeine and trimethadione [alone: r = 0.51 (P < 0.05); coadministered: r = 0.56 (P < 0.05)]. There were also weak correlations between the CL of trimethadione and the area under the serum concentration-time curves (AUC) of theobromine (r = -0.61, P < 0.05), paraxanthine (r = -0.69, P < 0.05) and theophylline (r = -0.60, P < 0.05), when the two drugs were administered alone. After combined administration, the correlation between the CL of trimethadione and the AUCs of the metabolites of caffeine were as follows: theobromine r = -0.63 (P < 0.05); paraxanthine r = -0.68 (P < 0.05); theophylline r = -0.65 (P < 0.05). These findings suggest that caffeine and trimethadione metabolism in healthy subjects is mediated by only in part by a form(s) of P450 enzymes involved.

The efficiency of multi-watt ultraviolet radiation generation by harmonics processes in β-BaB2O4 (BBO) can be improved by reducing thermal dephasing. The dephasing arises from local heating of BBO by the linear absorption of green (second harmonic) and ultraviolet (fourth harmonic) radiation by crystal defects that are induced by two-photon absorption of high peak power ultraviolet radiation. Such absorption can be reduced by decreasing the repetition rate to ∼1 kHz to allow the defects to decay between the laser pulses and/or heating BBO crystal to 150–200 °C to increase the decay rate of the induced defects.