On the Laws of Resistance to Turbulent Flow in Open Smooth Channels

It is generally considered that differing from the pipe flow, the flow in open channels has a free surface and waves appearing on water surface relate to some extent with .the laws of resistance on turbulent flow in open channels. According to the above opinion, instability of flow is connected with the mixing length of turbulence; and computing the velocity distribution by Prandtl's equation which expresses the flow near the wall, Froude Number is introduced with Reynolds Number in the laws of reistance on turbulent flow in open channels. Applying this theory, experimental results by authors, Dr. Matuo and R. W. Powell with smooth open channels can be explained within the region of sub- and supercritical flow, and, therefore, the difference between the laws of resistance to turbulent flow in pipes and that in open channels can be made clear

Theory of Flow on Road Surface

By solving the momentum equation of a thin sheet flow on road surface numerically with the condition of continuity obtained under the condition that rain falls on road uniformly, water depth and mean velocity of thin sheet flow and also frictional velocity related with soil-erosion of road surface are computed, and then the effects of camber shape and longitudinal slope of road surface on its drainage and stabilization are discussed

On the Analysis of Mechanism of River-Bed Variation by Characteristics

In this paper, a new method using the characteristic curve for analysing the mechanism of river-bed variation in a river in which the sediment is mainly transported as bed-load is presented. This method is introduced on the basis of the assumption that both of stream flow and river-bed profile vary gradually and the computation of river-bed variation is proceeded step by step. Various interesting phenomena of river-bed variation resulting from the sediment transport can be explained clearly by this characteristics method. As some examples, the deformations of mound and depression of river-bed in uniform flow of water and the deposition of sediment in reservoir are treated, and then the mechanism of their behaviours are ascertained

Neurochemical characterisation of lamina II inhibitory interneurons that express GFP in the PrP-GFP mouse

Background Inhibitory interneurons in the superficial dorsal horn play important roles in modulating sensory transmission, and these roles are thought to be performed by distinct functional populations. We have identified 4 non-overlapping classes among the inhibitory interneurons in the rat, defined by the presence of galanin, neuropeptide Y, neuronal nitric oxide synthase (nNOS) and parvalbumin. The somatostatin receptor sst2A is expressed by ~50% of the inhibitory interneurons in this region, and is particularly associated with nNOS- and galanin-expressing cells. The main aim of the present study was to test whether a genetically-defined population of inhibitory interneurons, those expressing green fluorescent protein (GFP) in the PrP-GFP mouse, belonged to one or more of the neurochemical classes identified in the rat.<p></p> Results The expression of sst2A and its relation to other neurochemical markers in the mouse was similar to that in the rat, except that a significant number of cells co-expressed nNOS and galanin. The PrP-GFP cells were entirely contained within the set of inhibitory interneurons that possessed sst2A receptors, and virtually all expressed nNOS and/or galanin. GFP was present in ~3-4% of neurons in the superficial dorsal horn, corresponding to ~16% of the inhibitory interneurons in this region. Consistent with their sst2A-immunoreactivity, all of the GFP cells were hyperpolarised by somatostatin, and this was prevented by administration of a selective sst2 receptor antagonist or a blocker of G-protein-coupled inwardly rectifying K+ channels.<p></p> Conclusions These findings support the view that neurochemistry provides a valuable way of classifying inhibitory interneurons in the superficial laminae. Together with previous evidence that the PrP-GFP cells form a relatively homogeneous population in terms of their physiological properties, they suggest that these neurons have specific roles in processing sensory information in the dorsal horn.<p></p&gt

Representation of Water Particle Velocity of Breaking Waves on Beaches by Dean's Stream Function

Experimental values of water particle velocity of breaking waves on uniformly sloping beaches differ considerably from the theoretical values of Stokes waves of the third order and cnoidal waves of the second approximation. In this paper, Dean's stream functions are calculated by giving simultaneously measured time variations of the water level of the breaking waves. Vertical distributions of horizontal water particle velocity at the crest phase, calculated by using these stream functions, are compared with experimental distributions in order to discuss the applicability of Dean's stream function method. These theoretical distributions can explain the experimental results well, although this stream function method assumes permanent waves in uniform depth. Dean's stream function can express an asymmetric wave profile as that of breaking waves on sloping beaches, while the Stokes wave theory has a symmetric wave profile. It is suggested that the breaking wave profile dominates the water particle velocity field of breaking waves

On the Rollwave-Trains Appearing in the Water Flow on a Steep Slope Surface

When we carefully observe a thin sheet flow with a suitable depth on a surface or in a channel of which the slope is greater than about 2%, we can see small continuous wave-trains moving to the down-stream with a uniform wavelength. For instance, we often find them on a road surface with a steep slope in a heavy rain, and the wave-trains in a thin sheet flow of rain-wat.er are called “rain wave-trains”. These wave-trains are rollwaves with a wave-height of several times the mean water depth and it is said that they have a close connection with the soil erosion, but researches on such wave-trains are few and unsatisfactory. In this paper, in order to obtain a foothold necessary to study the relations between the soil erosion and these rollwave-trains from the point of view .of civil and agricultural engineering, the hydraulic properties of the wave-trains are researched theoretically and experimentally by the wooden flume with a smooth bed. At first. a criterion in which the rollwave-trains begin to appear is determined, and then the various properties of the wave-trains, i.e. period, wave-length and .wave-velocity etc. are ascertained by using an electromagnetic oscillograph or a cathoderay oscilloscope and recording the wave-profile

Hydrodynamic Forces on a Circular Cylinder Placed in Wave-Current Co-existing Fields

The in-line hydrodynamic force acting on a circular cylinder in a wave-current co-existing field and its generating mechanism are discussed. This study focuses on the asymmetries of both the water particle movement and the resultant vortex property with respect to the cylinder as being the causes of an inherent generating mechanism of the hydrodynamic force in the wave-current co-existing field. First of all, the vortex property around a circular cylinder in the wave-adverse current co-existing field is examined by flow visualization tests. It is found that the vortex property depends on the flow characteristics around the trough phase when the wave-current composite velocity becomes maximum and can be represented with a newly proposed K.C. number for the co-existing field. Next, the characteristics of the in-line force are made clear by evaluating the drag coefficient and the mass coefficient in the expanded Morison's equation for the co-existing field. These coefficients can be well arranged by (K.C.)₂, which is one of the newly proposed K.C. numbers, and their characteristics coincide with the existing results in the wave-only field. The in-line hydrodynamic force in the co-existing field can be explained sufficiently by considering the vortex property in the same manner as clarified in the wave-only field

長期間喫煙による気管支唱息,肺気腫の病態的変化

The influence of long-term cigarette smoking on the pathophysiology of chronic respiratory diseases with obstructive ventilatory dysfunction was discussed in patients with asthma and pulmonary emphysema (PE). 1. In patients with asthma, significant differences in the pathophysiology of the disease were observed between smokers and nonsmokers. A positive RAST score against inhalant allergens, bronchial hyperresponsiveness, and LTB4 generation by leucocytes were significantly more increased in smokers than in nonsmokers. The values of FEV1/FVC and OLco were significantly more decreased, and % RV was significantly more increased in smokers than in nonsmokers. 2. In comparison of asthma with PE, IgE-mediated allergy was significantly more increased in smokers with asthma than in nonsmokers with asthma and in smokers with PE. The values of % FEV1, FEVl %, and % OLco were significantly higher in nonsmokers with asthma than in smokers with PE, however, the % OLco and % RV were not significantly different between smokers with asthma and those with PE. The % LAA of the lungs on HRCT was larger in patients with PE than in smokers and nonsmokers with asthma. The results suggest that cigarette smoking influences the pathophysiology of asthma and PE.長期間喫煙による気管支喘息および肺気腫の病態的変化について若干の検討を加えた｡1.気管支嘱喘息に関しては,喫煙例と非喫煙例との間に以下のような病態的特徴に差が見られた｡吸入抗原に対する特異的IgE抗体の陽性率,気道過敏性,白血球のI:TB4産生能はいずれも,喫煙例で非喫煙例に比べ有意の亢進を示した｡また,喫煙例では,非喫煙例に比べ,FEV1%や% DLcoは有意の低下,% RVは有意の増加傾向を示した｡2.喘息と肺気腫の比較では,IgEにmediateされるア レルギー反応は,喘息の非喫煙例や肺気腫(全て喫煙例)に比べ,喘息の喫煙例で有意の亢進が見られた｡% FEVl,FEV1,% DLco値はいずれも喘息の非喫煙例で,肺気腫と比べ有意に高い値を示したが,% DLcoと% RV値には,喘息の喫煙例と肺気腫の間に有意の差は見られなかった｡また,肺のHRCT上の% I.AAは,肺気腫において,喘息の喫煙例,非喫煙例いずれよりも有意に高い値を示した｡以上の結果より,長期間の喫煙が喘息や肺気腫の病態に影響を与えることが示された

温泉療法による気管支喘息に対する年間薬剤費の削減

Costs of drugs used for the treatment for 1 year were compared before and after spa therapy in 16 patients with asthma in relation to disease severity. Asthma severity was classified as : stage 1 (intermittent), 2 (mild persistent), 3(moderate persistent), and 4(severe persistent). 1. The total cost of drugs used for each pa-tient for 1 year clearty decreased in all groups. The % decrease of the costs of drugs in each group was 27.2% in patients with stage 1, 43.5% in those with stage 2 and 34.1% in those with stage 3-4 (mean 34.5% ). The reduction of the cost of bronchodilators was predominant in patients with stage 3-4, and the decrease in the cost of corticosteroids predominant in those with stage 2. The reduction of costs of antiallertgics, mucolytics, and antibiotics was predominant in patients with stage 2 and stage 3-4. The % reduction in the cost of corticostroids was remarkable in patients with stage 2. The % decrease in the costs of mucolytics and antibiotics was predomi-nant in patients with stage 2 and stage 3-4. The results obtained here suggest that the costs of drugs used for asthmatics could be reduced by long-term spa therapy, and the reduction of the costs was larger as asthma stage became more severe.気管支喘息16例を対象に,治療のために要した年間薬剤費が温泉療法により削減可能であるのかどうかについて,国際ガイドラインの重症度分類(stageト4)別に若干の検討を加えた｡1.年間の総薬剤費は重症度別の全てのグループにおいて明らかに減少した.2.その削減率は,ステージ1で27.2%,ステージ2で43.5%,ステージ3-4で34.1%であり,その平均は34.5%であった｡3.気管支拡張剤の薬剤費の減少はステージ3-4で高度であり,副腎皮質ホルモンの薬剤費の減少はステージ2で著明であった｡また,抗アレルギー薬,去痩薬,抗生物質などの薬剤費の削減は,ステージ2および3-4で高度であった｡4.削減率では,去壊薬,抗生物質の削減率が,2および3-4で著明であった｡ 以上の結果より,温泉療法により,気管支喘息の治療に必要な薬剤費は削減可能であること,そして,温泉療法による薬剤費の削減は職息の重症度が高い症例でより高度であることが示唆された

Modulation of mammalian spinal motor networks by group I metabotropic glutamate receptors : implications for locomotor control and the motor neuron disease amyotrophic lateral sclerosis

The present study examined the role of group I metabotropic glutamate receptors (mGluRs) in mammalian spinal motor networks and investigated the potential role of mGluRs in the fatal neurodegenerative disease amyotrophic lateral sclerosis (ALS). Group I mGluR activation was found to modulate locomotor-related activity recorded from ventral roots of in vitro mouse spinal cord preparations. Activation of group I mGluRs led to an increase in the frequency of locomotor-related bursts and a decrease in their amplitude. The cellular mechanisms underlying group I mGluR-mediated modulation were investigated using whole-cell patch-clamp recordings from spinal neurons. Recordings from motoneurons revealed a wide range of effects, some of which were expected to increase motoneuron excitability, such as membrane depolarisation and hyperpolarisation of action potential thresholds. However, the net modulatory effect of group I mGluR activation was a reduction in motoneuron excitability, likely reflecting a reduction in the density of fast inactivating Na+ currents. The activation of group I mGluRs also reduced excitatory synaptic input to motoneurons, suggesting that modulation of motoneuron properties and synaptic transmission both contribute to group I mGluR-mediated reductions in locomotor motoneuron output. Recordings from spinal interneurons revealed a smaller range of modulatory effects for group I mGluRs. The clearest effect on interneurons, membrane depolarisation, may underlie group I mGluR-mediated increases in the frequency of locomotor activity. Finally, the potential role of group I mGluRs in the pathogenesis of ALS was investigated using a mouse model of the disease. Although no major perturbations in group I mGluR-mediated modulation were demonstrated in ALS affected spinal cords, there appeared to be a difference in the intrinsic excitability of spinal interneurons between wild type and ALS affected animals. Together these data highlight group I mGluRs as important sources of neuromodulation within the spinal cord and potential targets for the treatment of ALS