Development Of Ears Research Articles

Effect of texture on earing in FCC metals: Finite element simulations

Abstract The effect of individual texture components on the development of ears in FCC metals was investigated using finite element modelling in conjunction with a texture-based sixth-order strain-rate potential. Five main FCC rolling and recrystallization texture components are considered: the cube, Goss (G), brass (B), S3 and copper (C). Also analyzed were mixed cube + B and B + S3 + C textures, as well as a typical rolling and a typical annealed aluminium texture. The shapes of cups drawn from sheets containing these textures are predicted, and the earing percentages are calculated. The contributions of individual texture components to ear formation are described. Some “ideal” textures that permit ear formation to be minimized are also discussed.

The evolution of tetrapod ears and the fossil record.

In the earliest tetrapods, the fenestra vestibuli was a large hole in the braincase wall bounded by bones of different embryological origins: the otic capsule and occipital arch components, and also, in all except the Devonian Acanthostega, the dermal parasphenoid. This means that the hole lay along the line of the embryonic metotic fissure. Early tetrapod braincases were poorly ossified internally, and no specialized opening for a perilymphatic duct is evident. It is arguable that the earliest tetrapods had neither a perilympllatic duct crossing the otic capsule nor a specialized auditory receptor in a separate lagenar pouch. The primitive tetrapod condition is found in the earliest amniotes, and the separate development of (1) a fenestra vestibuli confined to the limits of the otic capsule, (2) a specialized pressure relief window also derived from components on the line of the metolic fissure, (3) a nonstructural, vibratory stapes and (4) increased internal ossification of the internal walls of the otic capsule, can be traced separately in synapsids, lepidosauromorph diapsids, archosauromorph diapsids, probably turtles, and amphibians. This suggests separate development of true tympanic ears in each of these groups. Developments indicating the existence of a true tympanic ear in amniotes are first found in animals from the Triassic period, and a correlation with the evolution of insect sound production is suggested.

Potential yield of maize, determined by rates of growth and development of ears

Zea mays L. hybrids which differed in their expression of prolificacy were grown in field experiments and subjected to treatments which altered the amounts of nitrogen and solar radiation available to each plant. Detailed measurements were made of growth of the tassel and ears to determine the mechanisms through which plants adjusted their grain-yield to the environment. In preliminary field experiments, increases in plant population from 5 to 20 m −1 caused increased asynchronous flowering and reduced grain-yield per plant (but not per ha), due mainly to a 47% decrease in kernel number per plant. In the main field experiment, grain-yield of XL 80 (semi-prolific) and XL 81 (single-eared) were reduced by nitrogen deficiency and defoliation by 65 and 40% respectively, relative to controls. Yield per plant was reduced through (a) 1.3-2.7-fold reductions in number of potential kernels; (b) increases in asynchronous flowering; and (c) a 25% reduction in the number of spikelets differentiated by the first ear when grown under low N. Asynchronous flowering of the first ear increased because development of the ears was delayed relative to the tassel, and the relative elongation rate of silks was reduced. Treatment effects on ear growth were greater at lower ear positions. Spikelet number appeared to be related to the size of the ear, and was not influenced directly by treatments. We conclude that the processes which determine kernel number are highly sensitive to low levels of intercepted radiation or N supply.

Effect of gibberellic acid and indole-3-acetic acid on growth and differentiation of cultured ear inflorescences of maize ( Zea mays L.)

In order to explore the involvement of gibberellins and auxins in the development of maize ears, immature ear inflorescences were cultured in defined liquid media containing different concentrations of gibberellic acid (GA 3) and indole-3-acetic acid (IAA). The overall growth of the youngest ear promordia (5.1–10.0 mm long) was inhibited by higher concentrations of GA 3. A negative relationship between growth and increasing GA 3 concentration was demonstrated for young ear primordia. Growth of large ears (10.1–15.0 mm long), however, was stimulated slightly by increasing concentrations of GA 3. Expert at the lower concentrations of GA 3, female flowers overwhelmingly predominated. Growth of older meristems (10.1–15.0 and 15.1–20.0 mm long) was inhibited at higher concentrations of IAA. IAA promoted the maturation of female flowers in the developing ears but to a less consistent degree than GA 3.

Plasmin and Fibronectin Degradation in Chronic Secretory Otitis Media

Mucoid effusions from 39 children with secretory otitis media, altogether 42 specimens, were analyzed for proteolytic activity using radial caseinolysis procedures, for fibronectin using a solid-phase enzyme immunoassay, and for fibronectin fragmentation using immunoblotting. All samples contained proteolytic activity, tentatively identified as plasmin on the basis of comigration with purified human plasmin in zymographic analysis. In 19 specimens the plasmin level exceeded 1 microgram/mg of protein; the highest value recorded was 18.7 micrograms/mg. Low levels of net plasminogen activator activity were found in 12 specimens and identified as urokinase according to comigration with the urokinase standard in zymography. Fibronectin was detected in all but one of the 42 specimens; in seven specimens the levels exceeded those in normal plasma, calculated per milligram of total protein. Extensive fragmentation of fibronectin was found in 19 specimens, correlating with high plasmin levels. The results are indicative of an ongoing proteolytic process in secretory otitis media and suggest that plasmin-caused degradation of the fibronectin-containing basement membrane and subsequent formation of granulation tissue may be involved in the development of adhesive middle ears.

Studies on the growth and productivity of maize for whole-plant silage in the north-marginal area, Nemuro district in Hokkaido.

The object of this report is to clarify the dry-matter accumulation habits during the early vegetative growth period and to investigate the effect of the early growth on yield and quality of maize for whole-plant silage in the north-marginal area in Japan (where accumulated temperature from May to September is 2200°C.). Experiments were conducted for 6 years (1978∼'83), based on the same design. Wase-homare (an eary hybrid) was planted on three dates from mid-May to early-June in 1978∼'82 and late-May in 1983. The dry-matter weight in each organ was measured at the 4th-, 7th-, and 11th-leaf fully developed stages, and dry-matter yields were measured at harvesting date. The results obtained were as follows : 1. Root dry weight growth rate in each growth period from emergence to the 11th-leaf stage showed highly positive correlations with leaf expansion rate and top growth rate (TGR)(Table 1). 2. TGR during the period from emergence to the 4th-leaf stage showed highly positive correlations with daily maximum temperature and sunshine hours, but was not correlated with solar radiation (Table 2). 3. TGR in each growth period from emergence to the 7th-leaf stage showed a highly positive correlation with LAI. TGR during the period from the 7th-leaf stage to the 11th-leaf stage showed highly positive correlations with both of LAI and NAR (Table 3). 4. TGR during the period from emergence to the 4th-leaf stage showed highly positive correlations with ear DM yield, total DM yield and percentage of dry-matter in whole-crop, but was not correlated with stover DM yield (Fig. 4). 5. Thus it was concluded that the early growth is of great significance on the growth and development of ears which are essential for stable and high yield, and high quality of maize for whole-plant silage under severe conditions in the north-marginal area.

Growth of spring barley under drought: crop development, photosynthesis, dry-matter accumulation and nutrient content

SUMMARYThe effects of water deficit on growth of spring barley were analysed under five irrigation treatments. One crop was irrigated at weekly intervals from emergence throughout the growing season, and one was not irrigated at all after emergence. Soil water deficits in the other treatments were allowed to develop early, intermediate or late in the crop's development.Weekly irrigation produced a crop with a large leaf area index (maximum value 4) and maintained green leaf and awns throughout the grain-filling period. Early drought decreased leaf area index (maximum value 2) by slowing expansion of main-stem leaves and decreasing the number and growth of tiller leaves. Leaf senescence was also increased with drought. Drought late in the development of ears and leaves and during the grain-filling period caused leaves and awns to senesce so that the total photosynthetic areas decreased faster than with irrigation. Photosynthetic rate per unit leaf area was little affected by drought so total dry-matter production was most affected by differences in leaf area.Early drought gave fewer tillers (550/m2) and fewer grains per ear (18) than did irrigation (760 tillers/m2 and 21 grains per ear). Late irrigation after drought increased the number of grains per ear slightly but not the number of ears/m2. Thus at the start of the grain-filling period crops which had suffered drought early had fewer grains than irrigated (9·5 and 18·8 × 103/m2 respectively) or crops which suffered drought later in development (14 × 103/m2).During the first 2 weeks of filling, grains grew at almost the same rate in all treatments. Current assimilate supply was probably insufficient to provide this growth in crops which had suffered drought, and stem reserves were mobilized, as shown by the decrease in stem mass during the period. Grains filled for 8 days longer with irrigation and were heavier (36–38 mg) than without irrigation (29–30 mg). Drought throughout the grainfilling period after irrigation earlier in the season resulted in the smallest grains (29 mg).Grain yield depended on the number of ears, the number of grains per ear and mass per grain. Early drought decreased tillering and tiller ear production and the number of grains that filled in each ear. Late drought affected grain size via the effects on photosynthetic surface area.Drought decreased the concentrations of phosphorus, potassium and magnesium in the dry matter of crops, and irrigation after drought increased them. Concentration of nitrogen was little affected by treatment. Possible mechanisms by which water deficits and nutrient supply affect crop growth and yield are discussed.

稲線虫心枯病罹病株の高位節からの異常分枝について

On thc rice plant affected with Aphelenchoides bessevi, are often observed abnormal tillers which shoot out from higher nodes of mother culms, mostly from the 2nd to 4th nodes, being counted from up to down. The abnormal tillers occurred more frequently in the case of rice plant that absorped excess amount of nitrogenous fertilizer, during the development of ears of the mother culms. It was noticed that the abnormal tillers produced unripe ears and the mother culm was restricted its growth, causing reduction of the weight of ear, due to branching tillers.

Studies on the Affects of Soil Temperature upon the Growth of Crop Plants (II) : Effects of soil temperature upon the growth of wheat varieties (1)

The soil temperature is one of significant factors affecting the growth of plants, but no study was intended to examine the effect of soil temperature in winter period upon the growth and yield of wheat varieties. In this study, two winter wheat varieties: Konosu No. 25 and Norin No. 17 were used and seeded in the containers at Dec. 1. 1957. The soil temperature treatments were performed by placing pots in two constant temperature water tanks at outdoors maintained at about 6°C. and 11°C. in winter period (Jan. 11.-Mar. 31.) respectively, but those temperatures were rised about 5°∼6°C. during Apr. 1. to May 31. (Fig. 1) The results were as follows: 1) The growth of both top and root were retarded by low soil temperature (ca. 6°C.) and the degree of retardation in growth by low soil temperature was larger in root. 2) As the development of ears were promoted by high soil temperature (ca. 11°C.), heading, flowering and ripening times were hastened about one week by high soil temperature treatment. 3) Grain yield was significantly increased in the high soil temperature plot in Norin No. 17, but in Konosu No. 25, there was little difference between each plots. 4) From the above results, we concluded that the soil temperature in winter and early spring affects markedly on the vegetative and reproductive growth of wheat plants and there is varietal differences in the degree of retardation of growth by low soil temperature. It is supposed that the susceptibility to low soil temperature of Norin No. 17 may be related to the cold and snow resistance of this variety.

Studies on the Effects of Soil Temperature upon the Growth of Crop Plants (V) : Effects of soil temperature upon the growth of wheat varieties.(2)

The soil temperature is one of significant factors affecting the growth of plants, but no study was intended to examine the effect of soil temperature in winter period upon the growth and yield of wheat varieties. In this study, two winter wheat varieties: Konosu No. 25 and Norin No. 17 were used and seeded in the containers at Dec. 1. 1957. The soil temperature treatments were performed by placing pots in two constant temperature water tanks at outdoors maintained at about 6°C. and 11°C. in winter period (Jan. 11.-Mar. 31.) respectively, but those temperatures were rised about 5°∼6°C. during Apr. 1. to May 31. (Fig. 1) The results were as follows: 1) The growth of both top and root were retarded by low soil temperature (ca. 6°C.) and the degree of retardation in growth by low soil temperature was larger in root. 2) As the development of ears were promoted by high soil temperature (ca. 11°C.), heading, flowering and ripening times were hastened about one week by high soil temperature treatment. 3) Grain yield was significantly increased in the high soil temperature plot in Norin No. 17, but in Konosu No. 25, there was little difference between each plots. 4) From the above results, we concluded that the soil temperature in winter and early spring affects markedly on the vegetative and reproductive growth of wheat plants and there is varietal differences in the degree of retardation of growth by low soil temperature. It is supposed that the susceptibility to low soil temperature of Norin No. 17 may be related to the cold and snow resistance of this variety.

ON THE SPACING OF RICE UNDER THE DIRECT SOWING CULTURE

This experiment was carried out for three years (1947, 1948 and 1949) to know the adequate spacing of rice plants under sowing. We set up two plots, direct sowing and transplanting, the former divided into the following three plots, i. e. with 60, 120 and 240 plants per "tsubo" respectively and the latter into two plots, i. e. with 60 and 120 plants per "tsubo" The results were summarized as follows: (1) The rate of growth of plants sown directly was higher than that of plants tsansplanted during the period of vegetative growth, but after the development of the infant ears, the transplanted plants showed rapid growth, and at the time of heading no difference of culm length was recognized between these two plots. (2) As the spacing of plants became narrower, number of culms per plant was decreased, but on the contrary number of culms per "tsubo" was increased. (In the same spacing, number of culms per plant sown directly was greater than that of transplanted.) (3) Both growth and yield of the plot having 1.5 "shaku" spacing of rows were better than that of the plots having 1.0 and 2.0 "shaku" spacing. (4) As regard to "tillering" it was observed that the plants sown directly branched out tillers from lower nodes in comparison to the case of the transplanted, and more over the case of direct sowing it was observed that the tillering loci became upper as the spacing became narrower. (5) The yield of unhulled rice of the plots of direct sowing was higher than that of transplanted irrespective of the kinds of spacing, and the narrower the space, the greater became the yield in both the direct sown and transplanted plots.