I try to discuss about the so-called Drell ratio R(s) on the firm basis of both the validity of a unitarity aspect and a dispersion relation over electromagnetic current matrix elements. I first derive a useful inequality that bounds the asymptotic constant R of R(s) from the lower side, and then apply it to particular processes to examine infra-values of R or more appropriately of R^V's by which the individual contributions to R from the V-like degrees of freedom are meant (V = ρ^0, ω, φ and ψ). After all, I find the unitarity-lower-bound values to be about 3.5, 1, 1 and 0.5 for R^ρ, R^ω, R^φ and R^ψ, respectively, and therefore 〜6 for R, which are very suggestive to experiments.

抄録全体を表示

The substrate effect in enzyme reactions has been explained mostly in terms of an additional substrate binding site on the enzyme other than the catalytic site. A rate equation for the reaction is introduced according to the steady state mechanism as follows: v=(Ps³+Qs²+Rs)/(s³+Ls²+Ms+N), where the six parameters, L, M, N, P, Q, and R, can be determined by the least-squares method from the experimental points. The v vs. s curve has an parallel to the s abscissa, and can be classified into one of four types. The type A curve has an intersection with the and an apparent maximum velocity; the curve descends toward the . Type B has no intersection and no stationary point; the curve ascends toward the . Type C has two intersections and two stationary points, an apparent maximum velocity and a minimum velocity; the curve ascends toward the . Type D has no intersection and two stationary points; the curve ascends toward the . The equation was applied to the 3β-hydroxysteroid dehydro-genase [EC 1.1.1.145] reaction of rat testicular microsomes. The conversion of 3β-hydroxyandrost-5-ene-17-one was represented by type C, with an apparent maximum velocity of 0.338 nmole/min/mg protein at 0.912μM of the substrate concentration, minimum velocity of 0.108 nmole/min at 16.6μM, and saturating velocity of 0.169 nmole/min at infinite concentration of the substrate. The conversion of 3β-hydroxy-pregn-5-ene-20-one was of type B, having two inflexion points, 0.320 nmole/min at 2.735 pM and 0.814 nmole/min at 12.39μM, and a saturating velocity of 3.80 nmoles/ min at infinite concentration of the substrate.

抄録全体を表示

Effect of electric field on the paraconductivity σ₁ of Pb–Al₂O₃–Al junctions has been investigated, and a phenomenological analysis has been performed on the basis of Ferrell’s theory and the Langevin equation of the superconducting order parameter. The junction paraconductivity observed at temperatures slightly the transition temperature of the aluminum film is found to decrease with increasing the electric field E applied to the aluminum film parallel to converge rapidly to a temperature-independent proportional to E^−p where p=1.5±0.2. This at high fields is successfully derived with p=5⁄3 from the present phenomenological theory, whereas a discrepancy is found in the intermediate field region, where theory, predicts that σ₁ is inversely proportional to E but the observed values converge much rapidly to the .

抄録全体を表示

Although rational polynomial curves and surfaces have become standard forms in computer-aided design, they have many problems. For example, a Newton-Raphson algorithm for dealing with rational polynomial curves tends to be non-robust. This is a fatal problem. In the past, we proposed a new Newton-Raphson method for dealing with the rational polynomial curves. In the method, we homogenize the coordinates of a rational curve when it is applied to the Newton-Raphson algorithm. Then it becomes very robust.
This paper proposes a method of adapting the algorithm to the Newton-Raphson method for dealing with the surface-surface intersection problem. Like the case of a curve, the Newton-Raphson algorithm was found to be very robust when the coordinates of a curved surface are homogenized. In this paper, we discuss the reason why the conventional method tends to be non-robust while the new method is robust. The conventional method deals with a rational function that always has a horizontal as well as vertical ones while the new method deals with a non-rational function and thus has no . The result of our analysis points out that the cause of the non-robustness lies in the horizontal of the rational function inherent in the conventional Newton-Raphson method. Our numerical experiments show that our method is very robust.

抄録全体を表示

Dynamic viscoelastic properties, steady shear and biaxial extensional flow behaviors have been investigated for melts of potassium titanate whisker filled polyoxymethylene. A second plateau appears in the low frequency region of the storage modulus G', and the plateau value increases with whisker content. Addition of the whisker also increases the steady shear viscosity and the low strain rate of the biaxial extensional viscosity. The upturn of biaxial extensional viscosity from the low strain rate decreases by the addition of whisker due to suppression of polymer chain extension. Change in whisker dispersion and orientation in the melts was observed with scanning electron microscopy after quenching the samples in biaxial extensional flow. The degree of whisker orientation to the flow direction decreases with increasing strain rate in the range where the strain rate is much greater than the rate of whisker orientation and it is smaller than or comparable with the relaxation rate of the matrix chain. It is suggested that the matrix does not have enough power to orient the whisker in this range of strain rate.

抄録全体を表示

The decelerative part of the left ventricular isovolumic pressure decay is an important phase to make the heart ready for diastolic refill (lusitropy). Its widely used characterization by an exponential regression with zero pressure or coestimated provides empirically biased time constant estimates because of significant deviations of the pressure decay from exponentiality. We systematically analyzed the regression residua of these pressure decays in isolated ejecting rat, guinea pig, and ferret hearts. A four-parametric logistic (tangens hyperbolicus) function, together with a superimposed acustomechanic oscillation, yields normally distributed residua with standard regression error typically less than one per cent of the initial pressure; this is the first model with proved unbiased and statistically complete regressive extraction of the information provided by the time course of pressure decay. Equal values of the lusitropic parameters (logistic time constant and pressure ) were estimated even after the oscillatory component was removed from the regression model. Reliable estimates of the frequency, but not of the amplitude, can be obtained by fitting the oscillation model to the residua provided by the logistic; this two-step method is statistically weaker than the full one-step model, but it reduces computational effort. In conclusion, the four-parametric logistic, but not a three-parametric exponential or logistic model, suffices to obtain unbiased lusitropic parameters characterizing the left ventricular isovolumic pressure decay of small animal hearts.

抄録全体を表示

The test of homogeneity for normal mixtures has been used in various fields, but its theoretical understanding is limited because the parameter set for the null hypothesis corresponds to singular points in the parameter space. In this paper, we shed a light on this issue from a new perspective, variational Bayes, and offer a theory for testing homogeneity based on it. Conventional theory has not reveal the stochastic behavior of the variational free energy, which is necessary for constructing a hypothesis test, has remained unknown. We clarify it for the first time and construct a new test base on it. Numerical experiments show the validity of our results.

抄録全体を表示

植物の生育および分化に関与する環境要因の作用を量的に評価する数式モデルを確立するために, 白菜の花茎伸長 (抽苔) に複合的に作用する低温および日長をパラメータとしたモデリングを試みた.植物材料としては, 春播白菜「長岡交配耐病六十日」を用い播種後15日目 (2葉期) の幼苗を実験に供した.実験Iでは異なる処理温度, 処理時間を設定し, さらに処理後の日長を操作した.実験IIでは低温処理を行わず, 日長処理のみを行った.その結果, 実験IIでは花茎伸長は観察されなかったが, 低温処理を行った実験Iの長日条件において花茎の伸長が認められた.この花茎伸長は低温処理時間と日長によって花茎の最終値に明瞭な差異が認められ, また立ち上りの遅れにも差異がみられた.各処理条件における花茎長は低温処理終了からの経過日数を独立変数としたlogistic curveに適合した.その漸近値は低温処理時間と処理後の日長の関数として与えられた.さらにこのlogistic curve式を1次遅れ式に近似させ立ち上りの遅れを時定数とむだ時間の和として評価した.前報で遅れの評価パラメータとしてlog₁₀ΔT^1/2t_d² (ΔT=20℃-処理温度, t_dは低温処理時間) が用いられうることが明らかになったが, 日長をパラメータとして組み入れる場合, log₁₀PΔT^1/2t_d² (Pは日長の関数) の関数で遅れを評価しうることがわかった.したがって花茎伸長の立ち上りの遅れは処理温度, 処理時間, 日長の関数として与えられた.
このようにして与えられた漸近値と遅れ時間を満足する1次遅れ式を用いた花茎伸長の数式モデルから花茎伸長促進には, 低温処理時間が最も大きく作用し, 次に日長, 処理温度の順に作用の効果が小となることがわかった.また本実験において決定された低温処理条件の評価はキュウリ雌花分化に作用する低温条件のそれとよく対応した.

抄録全体を表示

The purpose of the present study was to examine the effect of unilateral lower limb suspension (ULLS) deconditioning on oxygen uptake kinetics. Eight healthy males underwent ULLS for 20 days and performed a series of 6-min square-wave transitions from rest to 60-W single-leg cycling exercises just before and after ULLS. To characterize the kinetics of the oxygen uptake response, a single exponential model was applied to the data until the end of the fast component omitted the first 15 s of the on-transit using a nonlinear least-squares fitting procedure. The following results were found: (i) the time constant of oxygen uptake was unchanged before and after ULLS; (ii) although there was no significant difference in the baseline and the asymptotic amplitude of the fast component, the , i.e., the absolute asymptotic amplitude of the fast component (the sum of the baseline and the asymptotic amplitude), and the end exercise oxygen uptake were decreased after ULLS; (iii) the contribution of the slow component to the total response of oxygen uptake was unchanged at pre- and post-ULLS. In conclusion, the in the fast component and the end exercise oxygen uptake were decreased after 20-d ULLS, though the response speed and the amplitude of the slow component of oxygen uptake were not changed. It is suggested that deconditioning as a result of limb disuse affects oxygen uptake response.

抄録全体を表示

According to HULL, incentive motivation (K) is expressed as K = 1 - 10 - a √ W and according to SPENCE, it is K = f (N, N_G, W_G, L_G, T_d, T_G?, X₁……X_N) and its basic mechanism is r_G-s_G. It has been supposed that the undifferentiated variables X₁……X_n contain the quality of incentive and other variable quantities.

抄録全体を表示

To investigate the mechanisms of altered myocardial diastolic stiffness and relaxation induced by myocardial oxygen deficit, we compared the hemodynamic effects of low flow ischemia (myocardial infarction model) and hypoxia in which the coronary flow was not reduced (angina pectoris model) in isolated retrograde perfused rabbit hearts. A 15-min hypoxia induced a significant increase in the left ventricular end diastolic pressure (LVEDP 10±3 to 21±7 mmHg, p<0.05), Po(-1±6 to 12±5 mmHg, p<0.01) and T_B(41±8 to 54±10 ms, p<0.05), where Po and T_B are the and the time constant of the isovolumetric left ventricular pressure decline (P=Po+A·e^-t/T_B), respectively. There was a close linear correlation between the delta Po and delta LVEDP (t=0.98, p<0.01), and between delta T_B and delta LVEDP (r=0.73, p<0.05). Low flow ischemia increased Po (0±4 to 2±3 mmHg, p<0.05) and T_B (43±4 to 50±11 mmHg, NS). When DPI 201-106, a cardiotonic agent, was given to the hypoxia moded by increasing the Ca⁺⁺ sensitivity of contractile proteins, further increases were observed in LVEDP (to 258 mmHg, p<0.05) and Po (to 157 mmHg, p<0.05). DPI also increased LVEDP (72 to 94 mmHg, NS) and Po(to 44 mmHg, p<0.05) in the ischemia model, However, T_B was not altered by DPI. Conclusions: 1) Po reflects the LVEDP, 2) The discrepancies between the changes of T and Po induced by DPI indicate different mechanisms underlying changes in LV diastolic stiffness and relaxation. 3) Both hypoxia and ischemia induced abnormalities in myocardial diastolic stiffness and relaxation.

抄録全体を表示

This paper describes a precise curve generation based on the envelope of a straight line fixed on the coupler link of a plane four-bar mechanism. The asymptotes, points of inflection and cusps of the envelope are discussed both analytically and graphically, and the normal deviation of the envelope due to small changes of kinematic parameters is formulated. Moreover, the tool-driving condition is analyzed for the generation of surfaces by means of a milling cutter or grinding wheel whose center reciprocates on the coupler link.

抄録全体を表示

MITSCHERLICHの生長過程にもとづいた理論的幹曲線を改良した新しい幹曲線式を提案する。樹幹形モデルの根拠にMITSCHERLICH式を選ぶ理由は,林木の直径および樹高生長が一般的にMITSCHERLICHの生長法則にしたがうことが認められており,さらに当年の連年生長量がその前年の連年生長量に比例するならばその生長はMITS-CHEHLICH式にしたがい,その逆も成りたつ,という事実にもとづく。新しい提案による樹幹曲線式は,梢端において髄から発生する初年生の直径連年生長量がその当年の樹高連年生長量に比例するという条件を仮定することにより,誘導された。この樹幹曲線式は下に凸の場合も表現でき,極限の樹幹形が三角形となることが理論的幹曲線と異なる点である。この樹幹形モデルについて理論的幹曲線と比較しながらその適用の可能性を検討した。

抄録全体を表示

1階差分方程式の一般解を利用して,生長データに適当な変換を行うことにより, MITSCHERLICH式のほかに, GOMPERTZ式.およびLogistic式を統一的に導けることを示した。さらに,.この方法を2階差分方程式比拡張して,同様にその一般解を利用し1上記の3種の生長曲線式に対応するそれぞれの多頂型生長曲線式を導いた.これらのうちのMITSCHERLICH式とGOMPERTZ式に対応する多項型の生長曲線式を,それぞれカラマシとトドマツの樹幹解析によってえられた5年間隔の胸高直径の生長データに当てはめ,それぞれのパラメータの推定方法を示すと同時に,適合度を検討した。これらの結果,生長の途中で,その傾向が変わるような生長過程に対して,十分な適合性をもつことが示され,その柔軟性を確かめることができた。

抄録全体を表示

The expression of the root locus by a self-conjugate equation is newly proposed as an analytical reprsentation of the root locus. The equation of the tangent at any point on the root locus is expressed in the simplest form by a self-conjugate equation. Thus both the condition for the breakaway point and the characteristic of the tangent at the breakaway point are made clear. Also the equation of the of the root locus is determined in a more detailed form than ever.

抄録全体を表示

An analysis similar to the van-Driest damping factor model for Newtonian fluids results in a viscoelastic damping factor for turbulent pipe flow of dilute polymer solutions. The turbulent relaxation time λ_t which must be used in the viscoelastic damping factor model is defined and correlated empirically. The present analysis is tested with the measured velocity distribution in the unsaturated drag reduction region, and friction factor in the unsaturated and saturated drag reduction regions. A comparison of the present model with two other well-known models, the elastic sublayer model of Virk et al. and the thickened laminar sublayer model of Seyer and Metzner, is made at the maximum drag reduction . From these comparisons it is concluded that the present model is valid to predict the friction factor and the velocity distribution in both the unsaturated and the saturated drag reduction regions.

抄録全体を表示