The Growth and Development of Caltha introloba F. Muell. II. The Regulation of Germination, Growth and Photosynthesis by Temperature

1989 ◽  
Vol 37 (4) ◽  
pp. 291 ◽  
Author(s):  
IF Wardlow ◽  
MW Moncur ◽  
CJ Totterdell
Keyword(s):  
Low Temperature ◽  
Root System ◽  
Growth And Development ◽  
Lag Time ◽  
Snow Melt ◽  
Optimum Temperature ◽  
Tap Root ◽  
Crown Tissue ◽  
The Mean ◽  
Maximum Temperatures

The germination of seeds of Caltha introloba F. Muell. on water was very slow with a lag time of 40-60 days. The optimum temperature for germination varied from 22-27°C and germination was very poor in the range from 0-15°C. Stratification of seeds at low temperature (1-2°C) for a period of 4 months, or treatment of the seeds with 3 × 10-4M GA3, more than halved the lag time for germination and considerably enhanced both the rate of germination and the extent of germination under low tempera- ture (0-15°C) conditions. It was concluded that C. introloba seed shed in the summer is unlikely to germinate in the short alpine herb field areas until after snow melt in the following spring. The optimum temperature for both growth and photosynthesis was approximately 15°C, which is close to the mean maximum temperatures for the summer months. Active photosynthesis however was observed at 0°C and therefore could occur throughout the year, except when the plants are covered by snow. Two important features in the establishment and growth of C. introloba appear to be the develop- ment of a deeply penetrating tap root system and the accumulation of carbohydrate reserves in the leaves and crown tissue.

THE EFFECTS OF PHOTOPERIOD, TEMPERATURE, AND FOOD SUPPLY ON RATE OF DEVELOPMENT AND DIAPAUSE IN COCCINELLA NOVEMNOTATA,

1967 ◽  
Vol 99 (6) ◽  
pp. 578-586 ◽  
Author(s):  
R. D. McMullen
Keyword(s):  
Experimental Data ◽  
Young Adult ◽  
Low Temperature ◽  
Egg Production ◽  
Gonad Maturation ◽  
Immature Stages ◽  
Optimum Temperature ◽  
Rate Of Development ◽  
Adult Females ◽  
The Mean

AbstractThe optimum temperature for rate of development and survival of immature stages of Coccinella novemnotata Herbst was found to lie between 70° and 80°F. Different photoperiods between 10 and 18 hours per day did not influence rate of development or survival. With a 16-hour photoperiod the mean number of eggs laid per female and mean longevity of females were greater at 70° than at 80°F, but not significantly so. At 90°F egg production was sharply curtailed and most eggs produced were infertile, probably due to inactivation of sperm in the male. Photoperiods of 10, 12, and 18 hours per day induced diapause in a large percentage of adult females; intermediate photoperiods of 14 and 16 hours per day were much less effective. Low temperature and lesser amounts of food available to adult females increased the effectiveness of the short and the long photoperiods for inducing diapause. The stage susceptible to induction of diapause, or conversely the initiation of gonad maturation, was determined to be the young adult from emergence to 7 days of age. The results of experimental data are related to a field study of the biology of this insect in California.

The effect of low temperature on growth and development of Phalaenopsis

2020 ◽  
Vol 52 (4) ◽  
Author(s):  
Yingjie Zhang ◽  
Jixia Sun ◽  
Xiangjun Pan ◽  
Wenjiao Guo ◽  
Jingwei Zhang ◽  
...  
Keyword(s):  
Low Temperature ◽  
Growth And Development

scholarly journals The implications of lag times between nitrate leaching losses and riverine loads for water quality policy

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
R. W. McDowell ◽  
Z. P. Simpson ◽  
A. G. Ausseil ◽  
Z. Etheridge ◽  
R. Law
Keyword(s):  
Water Quality ◽  
Mean Transit Time ◽  
Lag Time ◽  
Practice Change ◽  
N Leaching ◽  
N Losses ◽  
Leaching Losses ◽  
Nitrate N ◽  
The Mean ◽  
Lag Times

AbstractUnderstanding the lag time between land management and impacts on riverine nitrate–nitrogen (N) loads is critical to understand when action to mitigate nitrate–N leaching losses from the soil profile may start improving water quality. These lags occur due to leaching of nitrate–N through the subsurface (soil and groundwater). Actions to mitigate nitrate–N losses have been mandated in New Zealand policy to start showing improvements in water quality within five years. We estimated annual rates of nitrate–N leaching and annual nitrate–N loads for 77 river catchments from 1990 to 2018. Lag times between these losses and riverine loads were determined for 34 catchments but could not be determined in other catchments because they exhibited little change in nitrate–N leaching losses or loads. Lag times varied from 1 to 12 years according to factors like catchment size (Strahler stream order and altitude) and slope. For eight catchments where additional isotope and modelling data were available, the mean transit time for surface water at baseflow to pass through the catchment was on average 2.1 years less than, and never greater than, the mean lag time for nitrate–N, inferring our lag time estimates were robust. The median lag time for nitrate–N across the 34 catchments was 4.5 years, meaning that nearly half of these catchments wouldn’t exhibit decreases in nitrate–N because of practice change within the five years outlined in policy.

scholarly journals Effects of Temperature on the Flow and Heat Transfer in Gel Fuels: A Numerical Study

Energies ◽  
2020 ◽  
Vol 13 (4) ◽  
pp. 821
Author(s):  
Qin-Liu Cao ◽  
Wei-Tao Wu ◽  
Wen-He Liao ◽  
Feng Feng ◽  
Mehrdad Massoudi
Keyword(s):  
Heat Transfer ◽  
Low Temperature ◽  
Transport System ◽  
Apparent Viscosity ◽  
Thermal Design ◽  
Straight Pipe ◽  
Heating Wall ◽  
Supply Pressure ◽  
Flow And Heat Transfer ◽  
The Mean

In general, rheological properties of gelled fuels change dramatically when temperature changes. In this work, we investigate flow and heat transfer of water-gel in a straight pipe and a tapered injector for non-isothermal conditions, which mimic the situations when gelled fuels are used in propulsion systems. The gel-fluid is modeled as a non-Newtonian fluid, where the viscosity depends on the shear rate and the temperature; a correlation fitted with experimental data is used. For the fully developed flow in a straight pipe with heating, the mean apparent viscosity at the cross section when the temperature is high is only 44% of the case with low temperature; this indicates that it is feasible to control the viscosity of gel fuel by proper thermal design of pipes. For the flow in the typical tapered injector, larger temperature gradients along the radial direction results in a more obvious plug flow; that is, when the fuel is heated the viscosity near the wall is significantly reduced, but the effect is not obvious in the area far away from the wall. Therefore, for the case of the tapered injector, as the temperature of the heating wall increases, the mean apparent viscosity at the outlet decreases first and increases then due to the high viscosity plug formed near the channel center, which encourages further proper design of the injector in future. Furthermore, the layer of low viscosity near the walls plays a role similar to lubrication, thus the supply pressure of the transport system is significantly reduced; the pressure drop for high temperature is only 62% of that of low temperature. It should be noticed that for a propellent system the heating source is almost free; therefore, by introducing a proper thermal design of the transport system, the viscosity of the gelled fuel can be greatly reduced, thus reducing the power input to the supply pressure at a lower cost.

Fate of Selected Pathogens Inoculated into Foods Prepared in Slow Cookers1,2

1979 ◽  
Vol 42 (11) ◽  
pp. 872-876 ◽  
Author(s):  
J. RITTER ◽  
J. O'LEARY ◽  
B. E. LANGLOIS
Keyword(s):  
Staphylococcus Aureus ◽  
Low Temperature ◽  
Salmonella Typhimurium ◽  
Clostridium Perfringens ◽  
Health Hazard ◽  
Green Bean ◽  
Vegetative Cells ◽  
Salmonella Choleraesuis ◽  
Navy Beans ◽  
The Mean

Staphylococcus aureus, Clostridium perfringens. Salmonella choleraesuis, and Salmonella typhimurium were inoculated (108 cells or spores) into two slow cookers containing green bean casserole, baked navy beans, chicken cacciatore, barbecued ribs or pork pot roast, and their fate determined after cooking. Heating patterns also were determined at three positions inside the two cookers. None of the foods cooked in either of the slow cookers contained detectable levels of S. aureus or salmonellae. The similarity between C. perfringens vegetative and spore counts indicate that only spores were present in the cooked foods. Except for the green bean casserole cooked using a low temperature setting, cooking resulted in a 0.44–1.67 and 0.36–1.54 log count reduction, respectively, of vegetative cells and spores of C. perfringens. Counts of vegetative cells and spores after cooking the green bean casserole were approximately .18 and .30 log counts higher than the uncooked counts. The mean times for the coldest areas in Cooker A to reach 50 C were 2.57 and 0.97 h, respectively, for the low (80 watts) and high (160 watts) temperature settings. The mean times for the coldest areas in Cooker B (removable liner) to reach 50 C were 2.35 and 0.52 h for the low (130 watts) and high (260 watts) temperature settings, respectively. Results suggest that when the recommended quantities of ingredients are used and the proper cooking procedure followed, foods prepared in the slow cookers studied do not present a health hazard.

Growth and development of collagen fibrils in immature tissues from rat and sheep

1981 ◽  
Vol 212 (1186) ◽  
pp. 85-92 ◽  
Keyword(s):  
Electron Microscope ◽  
Transmission Electron Microscope ◽  
Collagen Fibril ◽  
Growth And Development ◽  
Collagen Fibrils ◽  
Diameter Distribution ◽  
Rat Tissues ◽  
Transmission Electron ◽  
The Mean ◽  
Fibril Diameter

The collagen fibril diameter distribution of four immature tissues from both rat and sheep have been determined from transverse sections observed in the transmission electron microscope. In many instances before birth, the form of the distribution for the tissues is both unimodal and sharp and the mean diameters of the distributions lie close to a multiple of 80 Å. For some tissues, the collagen fibril diameter distributions may be resolved into a number of components, each of which represents a population of fibrils with a diameter close to a multiple of 80 Å (8 nm). These data confirm and extend previous observations by the authors that small collagen fibrils all have diameters that are multiples of about 80 Å and that the fibril growth occurs by the accretion of 80 Å units. The form of the collagen fibril diameter distribution at birth is broad for the sheep tissues but narrow for the rat tissues, thus confirming that the range of fibril diameters at this stage of life reflects the differing degree of development of precocious and altricious animals.

THE TEMPERATURES OF SURFACE FIRES IN JACK PINE BARREN: I. THE VARIATION IN TEMPERATURE WITH TIME

1966 ◽  
Vol 44 (10) ◽  
pp. 1285-1292 ◽  
Author(s):  
David W. Smith ◽  
John H. Sparling
Keyword(s):  
Jack Pine ◽  
Maximum Temperature ◽  
Surface Fires ◽  
Mean Temperature ◽  
The Mean ◽  
Maximum Temperatures

The temperatures of 18 fires in an open jack pine barren near Timmins, Ontario, have been recorded. The maximum temperature recorded was 545 °C, although in other determinations fire temperatures in excess of 1000 °C were reached. The mean temperature of all fires was 340.6 ± 133.2 °C. Three fires at 230, 345, and 545 °C were considered in detail.The maximum temperature of a fire was normally recorded at heights of 5 cm or 10 cm above the surface. Maximum temperatures of hotter fires usually occurred at greater heights than cooler ones. Duration and the temperature ("intensity") of the fire are important aspects of fire studies.

What Is the Impact of Prior Authorization on the Incidence of Pediatric Tonsillectomy?

2020 ◽  
pp. 019459982096963
Author(s):  
Vanessa F. Torrecillas ◽  
Kaden Neuberger ◽  
Alexander Ramirez ◽  
Paul Krakovitz ◽  
Jeremy D. Meier
Keyword(s):  
Elective Surgery ◽  
Lag Time ◽  
Cross Sectional Study ◽  
Health Claims ◽  
Third Party ◽  
Prior Authorization ◽  
Cross Sectional ◽  
Before And After ◽  
The Mean ◽  
The Impact

Objective Third-party payers advocate for prior authorization (PA) to reduce overutilization of health care resources. The impact of PA in elective surgery is understudied, especially in cases where evidence-based clinical practice guidelines define operative candidacy. The objective of this study is to investigate the impact of PA on the incidence of pediatric tonsillectomy. Study Design Cross-sectional study. Setting Health claims database from a third-party payer. Methods Any pediatric patient who had evaluation for tonsillectomy from 2016 to 2019 was eligible for inclusion. A time series analysis was used to evaluate the change in incidence of tonsillectomy before and after PA. Lag time from consultation to surgery before and after PA was compared with segmented regression. Results A total of 10,047 tonsillectomy claims met inclusion and exclusion criteria. Female patients made up 51% of claims, and the mean age was 7.9 years. Just 1.5% of claims were denied after PA implementation. There was no change in the incidence of tonsillectomy for all plan types ( P = .1). Increased lag time from consultation to surgery was noted immediately after PA implementation by 2.38 days (95% CI, 0.23-4.54; P = .030); otherwise, there was no significant change over time ( P = .98). Conclusion A modest number of tonsillectomy claims were denied approval after implementation of PA. The value of PA for pediatric tonsillectomy is questionable, as it did not result in decreased incidence of tonsillectomy in this cohort.

THE ROLE OF EDUCATED LEADERS IN ECONOMIC GROWTH AND DEVELOPMENT: EVIDENCE FROM CENTRAL AFRICAN REPUBLIC AND SINGAPORE

2018 ◽  
Vol 65 (01) ◽  
pp. 81-102
Author(s):  
OLUWOLE OWOYE ◽  
OLUGBENGA A. ONAFOWORA
Keyword(s):  
Economic Growth ◽  
Growth And Development ◽  
Central African Republic ◽  
Economic Growth And Development ◽  
Highly Educated ◽  
Educational Attainments ◽  
Fundamental Causes ◽  
The Mean ◽  
Neoclassical Growth

This paper postulates that highly educated leaders matter in economic growth and development and that this is one of the fundamental causes of the differences in income between countries. To verify this assertion, we examine Central African Republic and Singapore within the neoclassical growth model that incorporates educational attainments of leaders as the functionally relevant explanatory variable. We found the mean years of schooling of educated leaders to be statistically and significantly different in both countries, but more importantly, educational attainments of leaders have a positive and statistically significant effect on economic growth in Singapore, but negative in Central African Republic.

Sign in / Sign up

Export Citation Format

Share Document