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締固め砂杭工法 (サンドコンパクションパイル工法) は, 密度増加による代表的な液状化対策工法である. 同工法の設計, すなわち圧入率あるいは置換率 (以下本論文では圧入率とする) とよばれる砂杭面積の原地盤に対する占有率の設定は, 原地盤N値, 細粒分含有率, 改良目標N値を用いる設計法で行われることが多い. 本論文では, 圧入後の増分N値に及ぼす細粒分含有率の影響に関する考察を行っている. そして, 既に提案した改良後N値の予測手法に考察結果を反映させ, 提案手法の改良・精度向上を行っている. さらに, 改良された予測手法を用いて, 砂杭圧入速度, 砂杭圧入間隔の締固め効率におよぼす影響について考察を行い, 砂杭圧入速度が締固め効率に影響をおよぼし, 圧入速度が遅い方が締固め効率は良くなることを示している.

サンドコンパクションパイル工法は, 密度増加による代表的な液状化対策工法である. 同工法の設計, すなわち圧入率あるいは置換率 (以下本論文では圧入率とする) とよばれる砂杭面積の原地盤に対する占有率の設定は, 原地盤N値, 細粒分含有率, 改良目標N値を用いる設計法で行われることが多い. 本論文では, 港湾・空港において行われた同工法の液状化対策としての実績を集め, 圧入率と改良後の杭間N値を調べ, 既存の設計法の妥当性を検討した. その結果, 実測値は圧入率が同一であれば改良前の原地盤N値が小さい方がN値の増加が大きくなっていたが, 既存の設計法はこの傾向を逆に評価することがわかった. そこで, 同工法の改良メカニズムについて繰返しせん断効果を考慮した方法を導入し, 圧入率設定のための新しい方法を提案した.

In order to maintain the depth of waterways and sea basins, huge amounts of soft clayey soil are dredged at many ports every year in Japan. In recent years, it has become more difficult to secure disposal areas for dredged soil due to environmental and economic restrictions. The effective use of the dredged soils is therefore required. Granular treated soil, which is dredged clay mixed with cement and polymer, has been developed as a countermeasure against this background and expected to be practically used for reclamation, backfill or subsoil materials. In this study, a series of dynamic centrifuge tests on applicability of granular treated soil to quay-wall backfill was conducted. The test results indicated that backfill of granular treated soil can reduce lateral displacement of caisson and that such backfill is resistant to liquefaction because of its high permeability.

It has been reported that acetylcholine hyperpolarizes the maximum diastolic potential of canine Purkinje fibers through a pathway involving a G protein and induces a decrease in their automaticity. It is unclear, however, whether the negative chronotropic action of acetylcholine in the presence of beta-adrenergic stimulation is due to the hyperpolarization of the maximum diastolic potential or a decrease in the slope of phase 4 depolarization. We used standard microelectrode techniques to study the negative chronotropic mechanism of acetylcholine in the presence of isoproterenol in adult canine Purkinje fibers. Fibers were incubated for 24 hours in Tyrode's solution alone (n = 10) or plus pertussis toxin (n = 10), and then superfused with acetylcholine (10(-9) to 10(-4) M) in the presence of isoproterenol (10(-7) M). Acetylcholine in the presence of isoproterenol significantly decreased automaticity without hyperpolarization of the maximum diastolic potential, and decreased the slope of phase 4 depolarization. The effects of acetylcholine on automaticity and the slope of phase 4 depolarization were attenuated by pertussis toxin. The present findings indicate that the negative chronotropic action of acetylcholine in the presence of isoproterenol is due to the decrease in the slope of phase 4 depolarization through a pathway involving a pertussis toxin-sensitive G protein and that it is not the result of hyperpolarization of the maximum diastolic potential.

土の弾塑性構成モデルに必要な土質パラメータを等体積一面せん断強さから決定することを目的として, 各地から様々な不撹乱粘性土試料を集めて等体積一面せん断試験を実施した. この実験結果と弾塑性構成モデルから導かれた等体積一面せん断強さの理論式とを比較した. 計算には, 関口と太田が提案した構成モデルを用いたが, 絶対値としての実験値と理論値 (経験式によるパラメータを用いた理論値) には相当な差があることがわかった. これは時間依存性の影響であると考えられるため, 等体積一面せん断強さの時間依存性を実験的に調べ, その影響を定量的に評価した.

Itching and infiltration of immune cells are important hallmarks of atopic dermatitis (AD). Although various studies have focused on peripheral mediator-mediated mechanisms, systemic mediator-mediated mechanisms are also important in the pathogenesis and development of AD. Herein, we found that intradermal injection of lysophosphatidic acid (LPA), a bioactive phospholipid, induces scratching responses by Institute of Cancer Research mice through LPA1 receptor- and opioid μ receptor-mediating mechanisms, indicating its potential as a pruritogen. The circulating level of LPA in Naruto Research Institute Otsuka Atrichia mice, a systemic AD model, with severe scratching was found to be higher than that of control BALB/c mice, probably because of the increased lysophospholipase D activity of autotaxin (ATX) in the blood (mainly membrane associated) rather than in plasma (soluble). Heparan sulfate proteoglycan was shown to be involved in the association of ATX with blood cells. The sequestration of ATX protein on the blood cells by heparan sulfate proteoglycan may accelerate the transport of LPA to the local apical surface of vascular endothelium with LPA receptors, promoting the hyperpermeability of venules and the pathological uptake of immune cells, aggravating lesion progression and itching in Naruto Research Institute Otsuka Atrichia mice.

To utilize soft clayey soils as construction materials, granulating technique is introduced. The technique converts soils dredged at ports and harbors to granular materials by adding small amounts of cement and polymer. Particle density, particle shape and particle distribution characteristics of cement-treated granulate soil (CTGS) as well as stress–strain relationships were investigated from laboratory tests. The results showed that CTGS was a lightweight material because small voids may be included in the particles. In addition, it was found that CTGS showed ductile behavior with the volume contraction when CTGS was subjected to shear deformation even if CTGS was initially prepared by compaction.

Infants with congenital long QT syndrome (LQTS) and 2:1 atrioventricular block (AVB) have been recognized as a clinical subset of children with LQTS. However, the genotype of this disorder is not well-known. We report an infant with LQTS and 2:1 AVB with a mutation of the SCN5A gene (LQT3). In some patients with LQTS and 2:1 AVB, the disorder may be due to mutation of the SCN5A gene (LQT3).

We studied the effect of intravenous, polyethyleneglycol-treated, human immunoglobulin, administered at 200 mg/kg per day (group A: n = 147; male 86, female 61; age < 1 year, 50) or 400 mg/kg per day (group B: n = 152; male 87, female 65; age < 1 year, 52) for five consecutive days and compared it with freeze-dried, sulfonated human immunoglobulin [group C: n = 152; male 87, female 65; age < 1 year, 51), administered at 200 mg/kg per day for five consecutive days, on the prevention of coronary artery abnormalities in Kawasaki disease. Echocardiograms were interpreted blindly and independently. Proportions of 87.1%, 95.4%, and 82.3% in groups A, B, and C, respectively, had no coronary artery abnormalities. The confidence limits of difference between the proportions of groups A and C, groups B and C, and groups B and A were -4.4% and 10.4%, 7.8% and 15.9%, and 4.0% and 10.8%, respectively. Duration of fever and serum immunoglobulin G (IgG) levels were correlated with the prevalence of coronary artery abnormalities. We concluded that intravenous, polyethyleneglycol-treated, human immunoglobulin and freeze-dried, sulfonated human immunoglobulin had clinically equivalent effects on coronary artery abnormalities, and that five daily doses of 400 mg/kg of intravenous, polyethyleneglycol-treated, human immunoglobulin is more effective than that of 200 mg/kg gamma globulin.

This is a qualitative and quantitative study of dog bundle branch and Purkinje cell development from day 0 to week 12 of life; we correlate the morphologic data with changes observed in the functional properties of developing dog Purkinje tissue. The bundle branch itself has a roughly cylindrical shape and is surrounded by a collagen sheath covered with endocardium. Within the bundle, Purkinje cells are packed closely together in fascicles distributed evenly around a central artery. Cross-sectional area doubles in the right bundle and increases 5-fold in the left bundle system between day 0 and week 12 of life. About one third of the bundle by volume is Purkinje tissue; the rest is extracellular space containing an increasing amount of collagen as the animal ages. Purkinje cell cross-sectional area is constant during the first week of life, but its length doubles and the cell changes from a relatively round to a more cylindrical shape. Between day 7 and week 12, cell diameter doubles; Purkinje cell surface area increases 5-fold and its volume almost 10-fold. As a consequence, the surface to volume ratio halves and approaches the value reported for adult dogs by week 12 of life. The percent of the intercalated disc occupied by nexal junctions virtually doubles by week 12, the same period over which Purkinje fiber conduction velocity increases. The disc itself becomes less dominant as the cell enlarges; the total percent of sarcolemma involved in its formation decreases by a fourth and has achieved the adult value by week 12 of life. As this happens, the percent of cell membrane facing on clefts increases almost 6-fold, so that the total percent of sarcolemma facing on small spaces (approximately 340A wide) is constant over the age period studied. The paucity of clefts in newborn tissue compared with the value reported for the adult dog may help explain the relative lack of responsiveness to extracellular potassium concentration of the resting membrane potential described for fetal Purkinje tissue. Within the Purkinje cell itself, the percent by volume occupied by mitochondria remains relatively constant over the age span studied, while sarcomeric mass increases 3-fold over the same period of time; these data are consonant with the relative resistance of this tissue to hypoxia.

The structures of two metabolites, isolated from the culture liquid of Alternaria porri , have been identified as zinnimidine and 5-(3′,3′-dimethylallyloxy)-7-methoxy-6-methylphthalide. The latter is the first reported isolation as a naturally occurring product.

In order to rationally select the mechanical test for evaluation of stripping resistance of asphalt mixture, the authors evaluated change of mechanical properties in the process of moisture damage of asphalt mixture. Then, the authors investigated influence of void ratio of asphalt mixture on the stripping resistance index by using Marshall compaction specimens and asphalt cores sampled from airport pavement for the purpose of discussing criteria on the index. As a result, it was shown that the change ratio of indirect tensile strength in the process of moisture damage was higher than Marshall stability and resilient modulus. And, there was a possibility that the void ratio showed no consistent relationship to stripping resistance index. 本論では，剥離抵抗性評価に用いる試験方法を検討するため，剥離に伴うアスファルト混合物の力学性状の変化を評価した．また，剥離抵抗性の評価指標の基準値設定に向けた検討として，室内作製供試体および現場で採取したコアを用いて空隙率が剥離抵抗性の指標に及ぼす影響を検討した．その結果，マーシャル安定度試験やレジリエントモデュラス試験と比較し，圧裂試験が剥離に伴う力学性状の変化を最も鋭敏に捉えられること，剥離抵抗性の指標として有効であると考えられた残留圧裂強度比と空隙率の関係については，骨材の性質の影響により一定の傾向を示さないことなどを示した．

We report 2 patients with necrotizing tracheobronchitis (NTB) associated with patent ductus arteriosus-dependent cyanotic congenital heart disease. The pathologic findings suggest that hypotension and decreased tracheo-bronchial perfusion were the major contributing factors in the development of NTB. Necrotizing tracheobronchitis developed in infants with pulmonary atresia and Ebstein's anomaly with pulmonary stenosis. Both infants required prostaglandin E1 infusion from early infancy, and presented with sudden onset of dyspnea and hypercapnea. In one infant, NTB developed prior to mechanical ventilation. In the other infant, NTB developed after 4 days of mechanical ventilation. Care of both infants involved minimal pressures and FiO2, adequate humidification, and optimal temperature of inspired gases; these factors probably did not play a role in the development or worsening of NTB. Both infants had hypotension and hypoxemia. These factors could have contributed to the development of NTB because of decreased perfusion pressure and tissue hypoxia. As the area of necrosis and its severity correlated with the area of blood supply served by the specific feeding arteries, we speculate that tissue hypoperfusion was the major cause of NTB. Pediatr Pulmonol. 2001; 32:480–483. © 2001 Wiley-Liss, Inc.

Objectives The goals of the present study were to develop a predictive coronary risk scoring system after intravenous gamma-globulin (IVGG) therapy of any dose for the different preparations currently used in the treatment of children with Kawasaki disease and to determine the predictive value of the system. The previously reported scoring systems were based on treatment with high-dose IVGG therapy at limited doses and were determined using investigative methods. Methods Four hundred and fifty-one patients were randomized into one of three groups and received either i.v. polyethylene glycol-treated human immunoglobulin at a dose of either 200 (n = 147) or 400 mg/kg per day (n = 152) or freeze-dried sulfonated human immunoglobulin at 200 mg/kg per day (n = 152) for 5 consecutive days. We documented 31 cases of coronary abnormalities (CA). Univariate and multivariate logistic regression was performed using 49 clinical variables and the resulting predictive model was validated. Results The duration of fever (odds (I day)/odds (- 5 days)= 0.158; 95% confidence interval (CI) 0.0385-0.648), hemoglobin (odds (Q1 = 10.3)/odds (Q3 = 11.6) = 3.97; 95% CI 1.92-8.20), IgG (odds (Q1 = 1,900)/odds (Q3=2,658)=2.72, 95% CI 1.18-6.25) and IgA (odds (Q1 =72)/odds (Q3= 160) = 0.415; 95% CI 0.253-0.680) levels after completion of gamma-globulin infusion were independent predictors. The model is quasi-cross validated and has acceptable sensitivity and selectivity. The estimated risk and observed occurrence of CA coincide. Conclusions Determinants of the risk of CA after IVGG therapy are a longer duration of fever, a lower IgG level, a higher IgA level and a lower hemoglobin level after IVGG infusion. This model is applicable for IVGG doses from 1 to 2 g/kg and for at least two different gamma-globulin preparations.

The paper reports results of the investigations on plastic deformation property of asphalt mixture under high contact pressure. Resistance to plastic deformation under high contact pressure was evaluated by means of Wheel Tracking (WT) test machine for simulating aircraft repetitive loadings. On the other hand, the author suggested the method for evaluating continuous air voids distribution of asphalt mixture in the depth direction by X-ray CT (computed tomography) scanner, and then tried to evaluate the property of the test specimen after the WT tests by using the method. As a result, following conclusions were shown. 1) The consolidated deformation under 1.48MPa contact pressure was larger than that under 0.63MPa contact pressure. 2) Void ratio of upper part of tested samples was less than that of samples before test whether the contact pressure was 1.48MPa or 0.63MPa. 航空機接地圧下におけるアスファルト混合物の塑性変形特性について，走行荷重に対するアスファルト混合物の塑性変形抵抗性および深さ方向の空隙分布の変化に基づき調査した．まず，WT試験機により航空機接地圧下でのアスファルト混合物の塑性変形抵抗性を評価した．次に，X線CTスキャナによるアスファルト混合物の深さ方向の空隙分布評価方法を検討し，これによりWT試験前後の車輪走行部の深さ方向の空隙分布の評価を試みた．その結果，航空機接地圧下では自動車接地圧と比較し圧密変形量が大きくなることやWT試験後の供試体上部の空隙率が接地圧の大小に関わらず試験前と比較し顕著に小さくなることなどを示した．