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Arterial blood pressures were taken by the Doppler ultrasound method in 134 unselected mature neonates (birthweights 2,600-3,900 grams) who were managed in the same manner after birth. Blood pressures were measured at 3-5, 10 and 30 minutes of life and, if indicated, intermittently during the next 24-48 h. Left and right arm pressures were identical or differed by only 1-2 mm Hg. Lower than normal blood pressures were found in 4 groups of infants: those born by cesarean section, those recovering from intrauterine asphyxia, those exposed to maternal anti-hypertensive therapy, and those whose mothers received thiopental within four minutes of delivery. Return of the low pressures to within the normal range was fastest following thiopental induction in the absence of fetal asphyxia and slowest after antihypertensive therapy.  相似文献   
3.
Two methods of assessing personal space in young children were examined in a group of 24 boys and 24 girls, aged 3 to 6 yr. When sex of peer figures and affect attributed to them were varied, 3-yr.-olds made distance-cue judgements based on affect but failed to use affect cues in structuring personal space. However, 4- to 6-yr.-olds readily perceived and used distance to communicate the affective quality of peer relations. On both measures, perception of distance cues increased with age. Only girls also used sex of figures as a social cue in depicting appropriate distances.  相似文献   
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This update describes a highly efficient organocatalytic aldol reaction of ketones and β,γ‐unsaturated α‐keto esters for constructing the chiral tertiary alcohol motif. With the application of 9‐amino(9‐deoxy)epi‐Cinchona alkaloid and an acidic additive as catalysts, both acyclic and cyclic ketones react with β,γ‐unsaturated α‐keto esters smoothly to afford aldol adducts in good to excellent yields and asymmetric induction. This protocol offers a new pathway for the construction of adjacent chiral carbon centers and the synthesis of chiral β‐hydroxy carbonyl compounds.  相似文献   
6.
This study investigated the effects of viscosity ratio (p) and composition on morphology development in an immiscible polymer system mixed under chaotic flow conditions. It was seen that morphology of the dispersed phase developed through a widely accepted route involving transitions from lamellas to fibrils and to droplets. It was found in experiments with p≥1 that the dispersed phase converted into droplets very rapidly with narrow droplet size distribution when p∼1. For higher values of p, the speed of morphological transitions slowed down, the droplet size distribution became wider, and much larger droplets were formed. Similar effects were observed at higher concentration of the dispersed phase. No self-similar scaling behavior was observed in the droplet size distribution, which can be attributed to the lack of self-similarity in the breakup of lamellas into fibrils.  相似文献   
7.
Recently, tapered fluidized bed has become more attractive because of the problems associated with conventional (cylindrical) beds like fluidization of widely distributed particles, entrainment of particles and limitation of fluidization velocity. There have been some investigations on hydrodynamics of uniform single size particles but there have been no detailed studies of homogeneous binary mixture of particles of different sizes and different particles in tapered beds. In the present work, an attempt has been made to study the hydrodynamic characteristics of homogeneous binary mixture of irregular particles in tapered beds having different tapered angles. Correlations have been developed for important characteristics, especially critical fluidization velocities and maximum bed pressure drops of homogeneous binary mixture of irregular particles in gas-solid tapered fluidized beds. Experimental values of critical fluidization velocities and maximum bed pressure drops have been compared with the developed correlations.  相似文献   
8.
A novel carbon-based Ni-Mo catalyst has been synthesized successfully from Jatropha curcas leaves using boric acid as a surface modifying agent. The Ni-Mo catalyst prepared on Jatropha curcas leaves had shown BET surface area of 316 m2/g whereas the Ni-Mo catalyst prepared without boric acid activation had shown BET surface area of only 14 m2/g. XRD and SEM data have shown that the active catalyst particles such as Ni and Mo have been found to be uniformly distributed. The inventive catalyst was studied for hydrotreating of gas oil, Jatropha curcas oil and 20% Jatropha oil in gas oil at 370°C, 90 bar H2 pressure, liquid hour space velocity of 1 h?1, and gas-to-oil ratio of 500 Nm3/m3 and the results obtained were found to be comparable with that of the commercial Ni-Mo catalyst supported on alumina.  相似文献   
9.
Field and pot trials were conducted to determine optimum management practices for usingLeucaena leucocephala (Lam. de Wit) leaves as a N source for crop production. Field trials with maize showed no benefit from split application of leucaena leaves or from application of fresh as opposed to dried material. Field trials also failed to show any difference between incorporation as opposed to surface application of leucaena leaves. This may be attributed to the low nitrogen response observed. Pot trials however, showed that soil incorporation of leucaena leaves was more effective than surface application in increasing plant dry weight.Leucaena leaves were not as effective as inorganic N in increasing maize grain yield (field trials) or dry matter production (pot trial). Unlike inorganic N, leucaena leaves had a significant residual effect on the succeeding maize crop. In decomposition studies, buried leucaena leaves decomposed more quickly than surface-applied leaves, and fresh leaves decomposed more rapidly than dried leaves.  相似文献   
10.
Intensity of glycolysis was studied under conditions of immobilization stress and adrenalectomy as well as with administration of adrenaline and hydrocortisone. The processes of aerobic glycolysis, activity of enzymes of the tricarboxylic acid cycle and mitochondria respiratory chain, content of total, free and protein-bound glycogen, glucose-I-phosphate, glucose-6-phosphate, pyruvate, alpha-ketoglutarate, cytrate and macroergs in the brain are shown to depend on the level of adrenal hormones producing a multilateral effect on a series of energy metabolism links.  相似文献   
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