Uppermost Position Research Articles

NUMERICAL STUDY OF THE FLOW PAST A CYLINDER EXCITED TRANSVERSELY TO THE INCIDENT STREAM. PART 2: TIMING OF VORTEX SHEDDING, APERIODIC PHENOMENA AND WAKE PARAMETERS

In Part 1 of the present study, it was found that the phase angle between the transverse force and the motion of a cylinder subjected to oscillations in the cross-flow direction, is strongly dependent on the parameters of the cylinder excitation. Since the phase angle is associated with the timing of vortex shedding, i.e., the phase of vortex formation with respect to the cylinder motion, the alteration of the phase angle at different conditions of forced excitation suggests a change in timing. For the investigation of timing at different excitation conditions, a detailed numerical visualization in the near-wake was conducted, by superimposing the vorticity contours on the streamlines when the cylinder displacement had reached the uppermost position. Flow visualization during a half-cycle for characteristic cases of the cylinder excitation was also performed, in an attempt to explain the alterations induced in the vortex spacing by the cylinder motion, which were also observed in Part 1. The numerical solution revealed a switch in timing when the excitation frequency is increased over the natural shedding frequency, which is accompanied by an instability in the near-wake which renders the wake aperiodic. Various examples of aperiodic flows are illustrated, and an explanation for the initiation of aperiodicity is provided. Finally, a balance between the circulation shed into the wake per oscillation cycle and that surviving in the vortices is conducted, while the distribution ofu ′rmsalong the wake centreline and the base pressure on the cylinder for various excitation conditions are also presented.

THE ROLE OF MAGMATIC PROCESSES IN THE FORMATION OF BANDED Li,F-ENRICHED GRANITES FROM THE ORLOVKA TANTALUM DEPOSIT, TRANSBAIKALIA, RUSSIA: MICROTHERMOMETRIC EVIDENCE

Quartz- and topaz-hosted melt, fluid, and mineral micro-inclusions have been studied to shed light on the origin of the massive and banded Li,F-enriched granites that host the Orlovka tantalum deposit, in Transbaikalia, Russia. Certain quartz and topaz grains, similar to most of the others in their morphology and structure, contain primary or secondary melt inclusions (or both), suggesting that these rocks are of magmatic origin. Their textural features are assumed to stem from different regimes of cooling of parental melts, as indicated by morphological peculiarities of rock-forming minerals. From thermometric and analytical studies of the melt and fluid inclusions, it follows that the Li,F-enriched granites were formed from melt that was enriched in F (~4 wt%) and H 2 O (~6 wt%), contained CO 2 in addition to H 2 O (mole fractions are ~0.08 and ~0.92, respectively), and had unusually low viscosity (~50 Pa·s at 660°C). The existence of quartz crystals that contain melt inclusions and columbite–tantalite microcrystals in the same growth-zones suggests that the melt became tantalite-saturated during early stages of crystallization at the top of the intrusion and late in the crystallization sequence at lower levels. With regard to results of model calculations, the uppermost position of the most Ta-rich melt in the pluton is considered to be caused by the removal of interstitial residual melt from deeper parts of the magmatic body and emplacement into a previously solidified crystalline carapace rather than by crystal settling.

Bose-glass and entanglement - disentanglement transitions in YBa2Cu3O7

The Bose-glass transition field BBG in YBa2Cu3O7 single crystals with columnar defects is tracked by the onset of the third harmonic generation. The progressive upward shift of the BBG(T)-line with the irradiation dose is followed by a saturation for the matching fields BΦ = 20 kG – 100 kG. The uppermost position of the Bose-glass transition is interpreted as a boundary between entangled and disentangled vortex liquids in virgin YBa2Cu3O7.

Host Genetic Variation in the Early Nodulation and Dinitrogen Fixation of Soybean

Soybeans [Glycine max (L.) Merr.] grown on soils low in N can exhibit N deficiency during early plant development. Improved early N2 fixation may alleviate this problem. Our objectives were to (i) examine genetic variation in early nodulation and N2 fixation of soybean, and (ii) identify traits useful in breeding for early nodulation and N2 fixation in this crop. Eighty‐six soybean lines showed considerable genetic variation in efficiency and speed of nodulation with Bradyrhizobium japonicum strain USDA 110. Eighteen lines were then reevaluated for nodulation efficiency with the B. japonicum strains USDA 123, UMR 161, and NA 6407 for differences in nodule number 5 to 12 d after inoculation (DAI) and for differences in plant dry weight, nodule fresh weight, acetylene reduction activity (ARA), nodule enzyme activity, leghemoglobin concentration, and nodule soluble protein concentration (SOLP) 10 to 17 DAI. The 86 lines differed in percentage roots nodulated (PRN; 26–93%) and number of nodules above the root tip mark (NARTM; 0.3–3.0), and in uppermost nodule position (− 17.5 to 19.5 mm). For the 18 lines that were reevaluated, mean PRN and NARTM values were greater for USDA 123 than for USDA 110 (65.1 vs. 57.9%; 1.4 vs. 1.0, respectively). For these lines, correlation analyses showed that PRN correlated with nodule number at 5 (r = 0.69**) but not 12 DAI, while nodule number 12 DAI correlated positively with nodule fresh weight, ARA, enzyme activity, and SOLP 17 DAI. Plant dry weight, nodule fresh weight, and nodule SOLP assayed at 17 DAI are suggested as traits for use in a breeding program to improve early nodulation and N2 fixation in soybean.

Topophysis affects the Potential of Axillary Bud Growth, Fresh Biomass Accumulation and Specific Fresh Weight in Single-stem Roses ( Rosa hybridaL.)

Topophysis, the effect on growth and differentiation of position of axillary buds along the shoot, was studied by propagating five-leaflet-leaf single-node cuttings which were excised from seven stem positions and grown as single stemmed plants. In Rosa hybrida‘Korokis’ Kiss®, ‘Tanettahn’ Manhattan Blue®, and ‘Sweet Promise’ Sonia®, following release of the buds from apical dominance by excision, morphogenetic development was studied until anthesis. The time from excision/planting until onset of bud growth, visible flower bud appearance, and anthesis was generally shorter in plants originating from apical bud positions than from basipetal positions. Topophysis mainly affected the onset of axillary bud growth; the earliest growth and development was found in cuttings from the second uppermost node position. This node tended to have the lowest plastochron value, which indicated the existence of a transition between sylleptic and proleptic buds. Stem length at visible flower bud and at anthesis generally increased as the cutting position changed basipetally until the second lowest position, and the number of five-leaflet-leaves at anthesis and the total number of nodes generally increased basipetally. For internode length, growth rate, and fresh biomass efficiency the cuttings taken from the uppermost and lowermost positions generally had significantly lower values than cuttings from all medial positions. At anthesis, plants originating from cuttings excised from lower medial positions generally had a higher fresh weight, greater flower stem diameter, and a significantly higher specific fresh weight than those plants originating from apical or basal positions. Among the cultivars, Sonia was the most efficient in increasing fresh biomass and had the highest growth rate, whereas Manhattan Blue possessed the highest specific fresh weight, indicating a higher plant quality. It is suggested that topophysis in Rosais an independent phenomenon intrinsic to the axillary bud.

Patterns of lateral preference in psychotic patients

Two tests of lateral preference (hand-clasping and arm-folding) were investigated in 50 adult right-handed healthy controls and in 42 right-handed psychotic patients. In the psychotics, hand-clasping and arm-folding with uppermost left positions were less evident than in the controls. In the psychotics with uppermost right positions in both tests (including handedness, i.e. unilateral right), good prognostic clinical features were most pronounced. These results, which were predominantly found in the males, are interpreted on the basis of possible relationships between hemispheric asymmetries and lateral preferences.

Nodulation efficiency of Bradyrhizobium japonicum strains with genotypes of soybean varying in the ability to restrict nodulation

Competition from existing soil rhizobia has limited the benefits from nitrogen fixation for soybean grown in the American Midwest. A strategy being considered to overcome this problem is the use of varieties that are restricted in nodulation with soil strains, but nodulate normally with inoculant bradyrhizobia. In this study we examine the efficiency in nodulation of strains of Bradyrhizobium japonicum that have been reported as restricted in nodulation with specific genotypes of soybean, using a root-tip marking procedure in growth pouches. When B. japonicum USDA110 was applied to the soybean cultivars Hardee and Fiskeby V at the rate of 3.50 × 104 cells/pouch, more than 75% of the plants were nodulated above the root-tip mark, and average uppermost nodule position was above the root-tip mark. By contrast, when this strain was applied in similar concentration to the soybean cultivar Peking, few plants developed nodules above the root-tip mark, and the average position of the uppermost taproot nodule was nearly 30 mm below this mark. Nodulation was improved at higher rates of inoculation, but even when 3.50 × 106 cells were applied to each pouch, less than 50% of the plants were nodulated above the root-tip mark. Bradyrhizobium japonicum strain CB1809 (=USDA136) was also efficient in nodulation with cv. Fiskeby V, but with cv. Hardee, less than 65% of plants were nodulated above the root-tip mark, irrespective of inoculation rate. Because restriction of nodulation with the strains initially tested was not absolute, we examined the patterns of nodulation obtained following the inoculation of two restriction hosts, Peking and PI371607. In pure culture, serogroup USDA110 strains failed to induce significant taproot nodulation of cv. Peking in Leonard jars, but did induce lateral root nodulation. However, in a glasshouse experiment contrasting soil- and seed-applied inoculant, lateral-root nodulation of the restriction host PI371607 by USDA123 was not significant.Key words: Glycine max, competition, restriction, nodulation.

The Casparian strip in pea epicotyls: Effects of light on its development

The Casparian strip, which is specific to roots, was studied in the epicotyls of dark-grown seedlings of pea (Pisum sativum L.) where it was found to have the same morphology and properties as the strip in roots. In dark-grown seedlings, the distance between the upper-most position of the Casparian strip and the bending point of the hook (about 37 mm) did not change during growth of the seedlings. In the uppermost 0.5-mm region of the region in which the Casparian strip could be detected by fluorescence microscopy, the plasma membrane was not firmly attached to the cell wall. The development of the Casparian strip continued for about 42 h after dark-grown seedlings were transferred to the light, indicating that (i) the cells that have been determined to form the Casparian strip in darkness form the strip in the light, and that (ii) it takes about 42 h for the cells to complete formation of the strip. Cells in the hook of dark-grown seedlings did not form a Casparian strip when such seedlings were transferred to the light. The Casparian strip was formed in rapidly elongating internodes of light-grown seedlings when the seedlings were transferred to darkness. Light did not control the formation of the Casparian strip in roots.

Gravitropic Response of Pulvini on the Elongating Stem of Rice and Their Interaction among Pulvini.

イネの伸長茎を人為的に横転すると, 通常3個の葉枕の屈曲によって鉛直方向に起きあがるが, 本研究は, それぞれの葉枕間の相互作用の有無を検討したものである. 材料は, 浮稲品種Habiganj Aman 8 (HA) と水稲品種ササニシキを用いた. 両品種とも同一の傾向を示したので本報ではHAの結果について述べる. 第1実験では, インタクト個体と茎切片 (葉枕3個を含む) の重力屈性反応を比較検討した結果, 両者は, ほぼ同様の傾向を示した. 第2実験では茎切片を用いて各葉枕の屈曲の経時変化を調査した. いずれの葉枕も水平配置後1, 2時間内に屈曲を開始し, 42時間後には, ほぼ屈曲を終了した. 第3実験では, 特定の葉枕を屈曲しないように物理的に固定して各葉枕の反応をしらべた. 下位節葉枕を固定した場合は, 下位節葉枕の屈曲減少分を上位節葉枕が屈曲して補うことが認められた. 一方, 上位節葉枕を固定した場合は, 下位節葉枕の屈曲増加は見られなかった. 第4実験では, 各葉枕を単離してから任意の順に並べかえ, 再結合した場合の各葉枕の屈曲反応を調べた. 葉枕間には5mmの隙間を設けた. 反応能力の低下した下位節葉枕を最上位に配置すると, 屈曲角度の総和は100度近くの値を示したが, 若い上位節葉枕を配置したときはほぼ90度となった. 以上の結果から, 各葉枕は化学物質の交換なしに, それぞれの位置を察知して重力に反応することが示唆され, さらに上位節葉枕ほど屈曲角度の総和が90度に近い値となるような正確な調節能力を保持していることが明かとなった.

Cultivar Variation in Traits Affecting Early Nodulation of Common Bean

Phaseolus vulgaris L. is inferior to other grain legumes in nodulation and N2 fixation, with early‐flowering cultivars particularly limited in the ability to satisfy their N needs through fixation. Extending the period of fixation could reduce the dependence of this crop on N‐fertilization. We sought bean accessions that were early to nodulate, and tried to identify specific traits that contributed to this ability. A root‐tip marking procedure was used to evaluate the earliness in nodulation of 40 accessions of common bean. With Rhizobium leguminosarum bv. phaseoli strain UMR1084 the accessions varied in uppermost nodule position relative to the root‐tip mark (RTM; −2.05 mm to +6.12 mm), number of nodules produced above the RTM (0.57‐3.93), and percentage of plants nodulated above this mark (37.7‐ 97.1%). Cultivars nodulated earlier with strain UMR1084 and UMR1899 than with strain UMR1242. Accessions RIZ23, RIZ108, N80068, and WI21‐58 nodulated rapidly with all strains tested, while ‘Mantequilla tropical’, RIZ21, and 0051 were slow to nodulate. selected bean accessions were then examined for inoculum dose response with UMR1084, for the percentage of infection sites giving rise to nodules, for the rate of development of nodules in the period 16 to 25 days after planting (DAP), and for plant growth and accumulation of N at 51 DAP. In these studies, ‘Puebla 152’ showed excellent nodule development and growth to the 25 DAP harvest, while the experimental line RIZ21 accumulated significantly more N and grew better in the period 25 to 51 DAP. The differences between these two accessions could be exploited in breeding programs for enhanced nodulation and N2 fixation in common bean.

EFFECT OF CUTTING POSITION ON ROOTING, AXILLARY BUD BREAK AND SHOOT GROWTH IN STEPHANOTIS FLORIBUNDA

Shoot growth of rooted cuttings of Stephanotis floribunda is often delayed for a shorter or longer period. In some plants shoot abscission can occur. This invistigation shows that cuttings from the upper part of the stock plant produce less roots and have a higher percentage of axillary bud break than cuttings from the more basal part of the vine. Shoot growth cessation and shoot abscission occur more frequently in cuttings from the uppermost positions. With increasing distance from the shoot tip the frequencies of shoot growth cessation and shoot abscission are lowered.

Relationship between gibberellin A4/7 concentration, time of treatment, and crown position on flowering of Piceaglauca

Treatment with the gibberellin mixture A4 and A7 (GA4/7) enhanced female flowering on mature white spruce (Piceaglauca (Moench) Voss). Time of treatment, crown position, and GA4/7 concentration influenced treatment success. GA4/7 treatment initiated before meristematic differentiation began (late June) enhanced female strobilus production, whereas those initiated after late June were ineffective. Shoots treated with 250 mg•L−1 GA4/7 bore significantly more female strobili than shoots that received 500 mg•L−1. Treatment did not affect female production on uppermost crown positions, male strobilus production, or seed yield per cone. Female strobili predominated from axillary buds centrally located on untreated shoots. GA4/7 treatments that enhanced female production shifted the distribution of strobili to more distal shoot positions.

Parental behaviour in Copris lunaris (Coleoptera, Scarabaeidae): care and defence of brood balls and nest

Abstract. 1. Nesting female beetles righted brood balls (so as to replace the egg or larva in the uppermost position) and repaired damaged balls. This behaviour required the presence of an egg or larva in the ball, or of a short‐lasting material found just after oviposition. The shape of the ball was also a righting stimulus since artificial ellipsoids were stood on end.2. Balls containing dichloromethane extracts of C.lunaris brood were righted and repaired. Eggs and larvae of several other Scarabaeidae did not release these responses but were destroyed.3. Righting behaviour was released when brood was absent from the top of the ball. The beetle then crawled vertically downwards and, if it encountered the displaced apex, a novel rolling action followed which automatically turned the ball towards the correct position.4. An opening made in the nest was repaired with soil excavated from the chamber floor. Clunaris adults and Aphodius fossor larvae were attacked if they were encountered in the nest.

Respiratory Responses Following Lifting the Legs in Normal Man

This study reinvestigates the problems of ventilatory drive linked to the rate of CO2 flow to the pulmonary circulation, and the respiratory response to the changes in cardiac output, which are both known to be capable of matching ventilation to perfusion so that the arterial blood remains isocapnic. Taking advantage of the known influence of posture on venous return, 21 healthy humans were subjected to the experimental maneuver which consisted of lifting the legs from the lower to uppermost position. This maneuver increased venous return to the right heart by bringing stagnant blood from the legs carrying more CO2. In all, 34 tests were performed. The results showed a rapid increase in minute ventilation of 12.3 percent. There were also increases in end-tidal CO2, CO2 production and cardiac output. All of the changes were fully reversible and reproducible. The results support the concept that a higher gain CO2 receptor system is operating during increased CO2 delivery to the lungs via the circulation. The possibility of reflex hyperpnea elicited from pressoreceptors localized in pulmonary circulation is also considered.

Tolerance to freezing and supercooling of interstitial turbellaria and polychaeta from a sandy tidal beach of the island of Sylt (North Sea)

Tolerance experiments on freezing and supercooling (without ice formation) were designed to determine correspondence between tolerance to low temperatures and spatio-temporal distribution of one turbellarian and five polychaete species from sandy beaches of the North Sea island of Sylt. Freezing tolerances are always less than supercooling tolerances. Dinophilus gyrociliatus is significantly more sensitive to freezing (LD50 value after 30 min of freezing:-3°C) than the others, whereas Stygocapitella subterranea is significantly less sensitive (50% mortality at-15.7°C after 30 min). The supercooling tolerances differ considerably among the species. The sequence of tolerances (LD50 values) is as follows: Microphthalmus sczelkowii (-2.9°C after 4 h); D. gyrociliatus (<1 h at-8°C); M. listensis (5.6 h at-8°C); Protodriloides symbioticus (8.2 h at-8°C); Notocaryoplanella glandulosa (66 h at-8°C); S. subterranea (72 h at-8°C). Species of sand flats (d. gyrociliatus, M. listensis, P. symbioticus) have lower tolerances than those of the beach slope (N. glandulosa, S. subterranea). Among the latter, tolerances increase with distance of the distributional area from low tide level. S. subterranea, a species occurring at the uppermost position in the intertidal, proves to be best adapted to both freezing and supercooling. Species preferring deeper regions of the beach (M. sczelkowii) show lower supercooling tolerances than surface dwelling forms. Northern species usually have higher tolerances to cold than southern ones, reaching their distribution limits near the island of Sylt.

Studies on Matter Production of Taro Plant (Colocasia esculenta SCHOTT) : I. Changes with growth in photosynthetic rate of single leaf

Photosynthetic ability of taro plant was investigated with an early variety, Ishikawa-wase, growing in pot. Photosynthetic rate of each single leaf was measured using the assimilation chamber as shown Fig. 1 for intact leaves. The results obtained were as follows: 1. Leaves developed successively with a time interval of several days. Total number of leaves in whole growing period showed 16-18. Life of the leaf differed with the leaf position. Duration from unfolding to withering was 40-45 days for lower leaves in early stage of growth and 55-80 days for upper leaves in later stage of that. There was large difference in leaf area among leaf positions. The higher the position of leat the larger the leaf area, excepting that a few leaves of uppermost position showed rather small leaf area. 2. Photosynthetic rate of each single leaf increased in new expanding leaf and reached a high level 14 or 15 days after expansion. It maintained the high level for about 10 days and, after that, declined gradually with aging. Thus, photosynthetic rate of single leaf varied with the leaf age. 3. The maximum rate of photosynthesis of single leaf under the conditions of light saturations was 30-35 mg CO2/dm2/hr for lower leaves and about 20 mg CO2 for middle and upper leaves. The light saturation point was about 70 Klx of radiation for younger leaves and 20-30 Klx for older leaves. 4. Optimum temperature for apparent photosynthesis of single leaf was approximately 30°C, while the photosynthetic rate did not show marked differences within the temperature from 22° to 35°C. 5. Temperature coefficient of dark respiration (O10) calculated was 2.05 for younger leaf and 1.62 for older leaf. Therefore, effect of temperature on respiratory activity differed with leaf age. 6. There was large difference with leaf position in maximum rate of photosynthesis of whole leaf area, showing 200 mg CO2/leaf/hr or more for upper leaves. That was due to the difference of leaf area of the position. Total value of maximum rate of photosynthesis accumulated for all of the leaves existing at the time of measurement showed marked increase from end of June, and it did not show the decline even in late September.

Effect of posture on the distribution of pulmonary ventilation in patients with increased closing volume.

Background: In normal adults, ventilation is uneven and greater in the base than the apex of the lung in tidal volume breathing. However infants have fragile chest wall and reduced elastic recoil, resulting in easy closure of peripheral airways especially in the dependent portion of the lung. So ventilation in infants is greater in the apex than the base of the lung. We assumed that in adults whose closing volume is increased, dependent portion could be easily collapsed during tidal breathing and ventilation could be greater in the uppear than than the lower portion of the lung. Methods: We measured spirometry and closing volume(CV) in normal controls and in patients with chronic lung disease. Also we measured fractional distribution of ventilation at supine, left lateral and right lateral decubitus with ventilation scan in normal controls, patients with normal closing volume and patients with increased closing volume. Results: The subjects consisted of 7 normal controls(mean , years). 6 patients with normal CV( years) and 7 patients with increased CV( years). 1) Normal controls have mean() FVC of predicted value, and CV . Patients with normal CV have FVC and CV . Patients with increased CV, have FVC and CV , CV was significantly different between two patient groups(p at supine, at dependent and at left uppermost position. In patients with normal CV mean fractional ventilation to left lung was at supine, at left dependent and at left uppermost position. In patients with increased CV mean fractional ventilation to left lung was at supine, at left dependent and at left uppermost position. In normal controls and patients with normal CV, ventilation to left lung at left dependent position tends to be higher than that at supine position but without statisitical significance and it was significantly lower at left uppermost than at left lung dependent position. In patients with increased CV, ventilation to left at left dependent position tends to be higher than that at supine position but without significance and it was significantly higher at left uppermost than that at left dependent position. Conclusion: These data suggest that in patients with increased CV ventilation to one side of lung could be higher at uppermost than at dependent position on lateral decubitus during tidal breathing and this fact should be taken into account in positioning of patients with unilateral lung disease.

Relation between Water Level and Capillarity in Shin-Tainai Gas Field and Tainaigawa Area, Niigata Prefecture

The reservoir is found in the condition of equilibrium between the gravitational andcapillary forces. Then, the individual rock and fluid characteristics of the reservoir control the distribution of various fluids in the reservoir and the height of transition yone. Generally thers is no sharp boundary line between oil and water level or between gas and water level in the reservoir. In Shin-Tainai gas field and Tainaigawa area, Kita-Kambara Plain, Niigata Prefecture, several reservoirs have deposited at Shiiya stage, Miocene. It is shown that each members encountered different gas-water contact levels. Provided the hydrodynamic conditions do not exist there, such different or tilted contacts may be the result of change in rock characteristics (permeability and porosity) which affect the capillary pressure of the reservoir and the height of the transition zone. As the porosity and permeability of reservoir become lower, the thickness of the transition zone becomes larger due to the higher capillary pressures. In fact, core-derived capillary pressure measurement data can not be available in Shin-Tainai gas field, but it was shown that water distribution as determined from electric logs and capillary pressure measurement are normally in good agreement. Approximate position of the gas-water contact can be determined from other data, then the height of transition zone can he estimated. It is obvious that amount of structural closure for water-free production must be in excess of vertical height of transition zone. At Shin-Tainai NS-4 well, II horizon (upper Shiiya formation), composed of very fine sand and shale alternation, has extremely low porosity and permeability. In spite of its relatively higher level (below sea level, -1, 700_??_-1, 750 meters) and apparent cycle skipping on sonic log, considerable amount of water produced from this horizon. According to the water saturation versus vertical heights plot, the capillary pressure is estimated to generally high and the height of transition zone is abnormally thick (about 80_??_100 meters). Although the total amount of closure of this horizon is about 200 meters, the vertical height from the spill point to the uppermost position of this reservoir of this well is only 90 meters below, water-free production can not be expected. At the same well, IV horizon (middle Shiiya formation), composed of coarse to medium sand and shale alternation, has a range of porosity from 20 to 25 percents. Water saturation versus vertical heights plot shows the lower capillary pressures and the thinner transition zone. Although this horizon is encountered at relatively lower level (below sea level, -1, 900 meters ±), it is natural that large amount of free gas column exist there, because this horizon has same amount of closure as II horizon mentioned above. Other field examples were shown for the understanding of the relation between the distribution of various fluid and capillarity in the reservior.

Experimentally induced variations in vitelline artery development and circulatory pattern in the early chick embryo.

AbstractWhite Leghorn eggs were incubated to desired prevasular stages. Each embryo, upon its intact yolk and surrounded by albumen, was rolled from the shell into a sterile 50 ml beaker. In an uppermost position, the blastoderm was lightly stained with neutral red. Three types of localized cuts were made as indicated below, and the beaker‐embryo unit placed in a sterile humidified chamber for further incubation. Results: (1) Unilateral cuts adjacent to the body and parallel with its axis blocked or suppressed formation of the vitelline artery on the cut side, even though healing occurred; (2) A specific site was found in the area pellucida opposite the sinus rhomboidalis which, when lightly cut perpendicular to the body axis, resulted in blockage or shifting of the final junction between aorta and vitelline artery as far cephalad as the thirteenth somite level. Formation of a dual final junction with the aorta also occurred. (3)Transverse cuts through the body axis and into the area pellucida bilaterally, frequently resulted in bilateral blockage or bilateral shifting. In still other cases, growth of a functional loop around the cut to connect the aortae in anterior and posterior segments with the vitelline artery were observed. Other unique circulatory patterns are described.Apparently, slight interference with the capillary plexus which precedes the vitelline artery causes anomalous development. Circulation is considered a major factor in arterial differentiation. Cutting probably alters the plexus and relation of its components to the onset of blood flow.

Studies on the Stiffness of Culms in Barley Plants (Hordeum sativum, JESSEN) : 10. Bending rigidity of culms.

A brittle culm variety, Sekitorisai-No. 1, and a stiff culm variety, Haganemugi (Hordeum sativum, JESSEN) were used to study the relation between YOUNG's modulus (E) and bending rigidity (EI) in internodes and nodes. YOUNG's modulus measured by OLSEN's type stiffness tester, and bending rigidity calculated from YOUNG's modulus and moment of inertia. There was not so great differences of YOUNG's modulus between both varieties, but YOUNG's modulus in Sekitorisai-No. 1 was slightly larger than of Haganemugi. Regarding the position of internodes and nodes, it was recognized that the uppermost position of internode and node had the largest YOUNG's modulus, medium in the base position, and the smallest in the intermediate position. The bending rigidity of Haganemugi is larger than that of Sekitorisai- No. 1, and it is larger in the base position, and on the other hand small in the upper position. The stiffness of culm has relation to the diameter of buckling load, and buckling load is related to the bending rigidity as long as the culm length is constant. In theoretically, YOUNG's modulus and moment of inertia have the same relation to the bending rigidity. In the case of same bending rigidity with the different mome nt of inertia, YOUNG's modulus are larger in culms with smaller moment of inertia, and vice versa. So the increase of YOUNG's modulus is valuable for concering the stiffness of culms with the small moment of inertia. Moment of inertia was determined by the outer diameter and the inner one. A large moment of inertia was regarded in culms with large outer diameter or the with small inner diameter. In the case of the same moment of inertia with different outer and inner diameter, the cross section area of culm tissue was small in culms with large outer and inner diameter than with small outer and inner diameter.