Some Aspects of the Growth of Single and Mixed Populations of Flagellates and Ciliates

1956 ◽  
Vol 33 (4) ◽  
pp. 627-644
Author(s):  
SMILJA MUČIBABIĆ
Keyword(s):  
Population Growth ◽  
Maximum Yield ◽  
Maximum Size ◽  
Multiplication Rate ◽  
Size And Shape ◽  
Different Temperatures ◽  
Temperature Ranges ◽  
Lower Temperature Range ◽  
Lower Temperature ◽  
The Relationship

Populations of Chilomonas paramecium have been maintained in a standard concentration of nutrient medium (0.1% beef-extract with 0.1% sodium acetate), at eight different temperatures, from 5 to 36° C. The temperatures 5 and 36° C. did not support the growth of a population. The rate of population growth increased with increase of temperature up to a maximum, and then decreased. The maximum yield, on the other hand, was not affected, within wide limits, by different temperatures. The relationship between temperature and maximum size of population was different when maximum size was expressed in total number of organisms from that when maximum size was expressed in terms of total volume of organisms. In the former case, the maximum size increased with the increase of temperature; while in the latter it decreased with increase of temperature. Bělehrádek's temperature coefficient, b, of the multiplication rate of Chilomonas did not show significant differences for different temperature ranges, while the coefficients Q10, and the thermal increment µ were larger for the lower temperature range. The size and shape of Chilomonas were found to depend on the temperature and on the age of the population. With increase in temperature, the size of organisms decreased to a minimum and then increased again, so that organisms were largest at extreme temperatures. In general, the organisms were more slender at lower than at higher temperatures. At all temperatures, the flagellate increased in size at the beginning of population growth and later decreased. Variation in size and shape was greatest at the beginning of growth and during transition to the maximum stationary phase.

Evaluation of CO2 Absorbent/De-Absorbent by AAO/CaO Membrane

2013 ◽  
Vol 690-693 ◽  
pp. 1856-1859
Author(s):  
Chien Chon Chen ◽  
Yen Po Wang
Keyword(s):  
Anodic Aluminum Oxide ◽  
Sol Gel ◽  
Core Shell ◽  
Anodic Aluminum ◽  
Temperature Ranges ◽  
Higher Temperature ◽  
Co2 Absorbent ◽  
Lower Temperature ◽  
The Relationship ◽  
Fuel Material

This paper discussed the fabrication of anodic aluminum oxide (AAO)/CaO core-shell membrane by anodization and sol-gel processes and evaluated the relationship between the Al2O3/CaO and CO2 by thermodynamic calculation. According to thermodynamic property that CaO can reacts with CO2 forming calcium carbonate (CaCO3) in a lower temperature ranges, CaCO3 can also be decomposed to CaO in a higher temperature ranges. Because the reversible reaction property that CaO can be a CO2 absorbent/ de-absorbent. We address that AAO based on core-shell nanotubes structure to achieve such a demand. The captured CO2 can further convert to fuel material of hydrocarbons.

Studies on the Toxicity of insecticide Films. II.—Effect of Temperature on the Toxicity of DDT Films

1949 ◽  
Vol 40 (2) ◽  
pp. 239-265 ◽  
Author(s):  
S. Pradhan
Keyword(s):  
Effect Of Temperature ◽  
Two Factors ◽  
Different Temperatures ◽  
Insecticidal Action ◽  
Higher Temperature ◽  
Effects Of Temperature ◽  
Insect Activity ◽  
Lower Temperature ◽  
Toxicity Relationship ◽  
The Relationship

1. A series of exploratory experiments on the relationship between temperature and toxicity of DDT films to adults of Tribolium castaneum, and larvae of Plutella maculipennis, are described. The main conclusions with T. castaneum are:—(a) When the insects are continuously kept on the film at different temperatures there is a higher kill at higher temperatures.(b) When the insects are exposed to the film for about 24 hours at the same temperature and then kept away from it at different temperatures there is a higher kill at the lower temperature.(c) When the insects are kept on the film at different temperatures for about 24 hours and then kept away from the film for reaction at the same temperature, there is a higher kill in those kept on the film at the higher temperature.(a) and (b) above apply equally to larvae of P. maculipennis but (c) is reversed. The probable cause of this reversal appears to be the observed fact that at higher temperatures these larvae cover the film with much more silk thread and thus avoid contact to a greater extent than at lower temperatures.2. A review of literature, in the light of the conclusions arrived at, indicate that many of the observations made upon the temperature-toxicity relationship can be accounted for by the following generalisations:—(a) Insect resistance to poisons changes with temperature as do its other vital activities, increasing up to a critical degree and afterwards declining.(b) The amount of poison reaching the site of action in unit time also varies with the temperature, generally but not always, increasing with its rise. Insect activity, especially locomotor and respiratory, may play an important part in these effects.(c) The apparent effects of temperature on insecticidal action is the combination of these two factors, namely, resistance and pick-up.

scholarly journals The Respiration of some Planktonic copepods II. The Effect Of Temperature

1953 ◽  
Vol 31 (3) ◽  
pp. 447-460 ◽  
Author(s):  
D. T. Gauld ◽  
J. E. G. Raymont
Keyword(s):  
Respiratory Rate ◽  
The Body ◽  
The Other ◽  
Effect Of Temperature ◽  
Acartia Clausi ◽  
Temora Longicornis ◽  
Different Temperatures ◽  
Planktonic Copepods ◽  
The Difference ◽  
The Relationship

The respiratory rates of three species of planktonic copepods, Acartia clausi, Centropages hamatus and Temora longicornis, were measured at four different temperatures.The relationship between respiratory rate and temperature was found to be similar to that previously found for Calanus, although the slope of the curves differed in the different species.The observations on Centropages at 13 and 170 C. can be divided into two groups and it is suggested that the differences are due to the use of copepods from two different generations.The relationship between the respiratory rates and lengths of Acartia and Centropages agreed very well with that previously found for other species. That for Temora was rather different: the difference is probably due to the distinct difference in the shape of the body of Temora from those of the other species.The application of these measurements to estimates of the food requirements of the copepods is discussed.

scholarly journals The effect of air temperature on hospital admission of adults with community acquired pneumonia in Baotou, China

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Wenfang Guo ◽  
Letai Yi ◽  
Peng Wang ◽  
Baojun Wang ◽  
Minhui Li
Keyword(s):  
Hospital Admission ◽  
Air Temperature ◽  
Meteorological Data ◽  
Community Acquired Pneumonia ◽  
Adult Patients ◽  
Distributed Lag ◽  
Specific Effects ◽  
Lower Temperature Range ◽  
Lower Temperature ◽  
Inner Mongolia Autonomous Region

AbstractThe relationship between air temperature and the hospital admission of adult patients with community-acquired pneumonia (CAP) was analyzed. The hospitalization data pertaining to adult CAP patients (age ≥ 18 years) in two tertiary comprehensive hospitals in Baotou, Inner Mongolia Autonomous Region, China from 2014 to 2018 and meteorological data there in the corresponding period were collected. The exposure–response relationship between the daily average temperature and the hospital admission of adult CAP patients was quantified by using a distributed lag non-linear model. A total of 4466 cases of adult patients with CAP were admitted. After eliminating some confounding factors such as relative humidity, wind speed, air pressure, long-term trend, and seasonal trend, a lower temperature was found to be associated with a higher risk of adult CAP. Compared to 21 °C, lower temperature range of 4 to –12 °C was associated with a greater number of CAP hospitalizations among those aged ≥ 65 years, and the highest relative risk (RR) was 2.80 (95% CI 1.15–6.80) at a temperature of − 10 °C. For those < 65 years, lower temperature was not related to CAP hospitalizations. Cumulative lag RRs of low temperature with CAP hospitalizations indicate that the risk associated with colder temperatures appeared at a lag of 0–7 days. For those ≥ 65 years, the cumulative RR of CAP hospitalizations over lagging days 0–5 was 1.89 (95% CI 1.01–3. 56). In brief, the lower temperature had age-specific effects on CAP hospitalizations in Baotou, China, especially among those aged ≥ 65 years.

scholarly journals Optimizing the Properties of La0.8Sr0.2CrO3 Thin Films through Post-Annealing for High-Temperature Sensing

Nanomaterials ◽  
2021 ◽  
Vol 11 (7) ◽  
pp. 1802
Author(s):  
Dan Liu ◽  
Peng Shi ◽  
Yantao Liu ◽  
Yijun Zhang ◽  
Bian Tian ◽  
...  
Keyword(s):  
Thin Film ◽  
Thin Films ◽  
Annealing Temperature ◽  
Rf Sputtering ◽  
Maximum Size ◽  
Cross Sectional ◽  
Post Annealing ◽  
Maximum Conductivity ◽  
Different Temperatures ◽  
Post Annealing Temperature

La0.8Sr0.2CrO3 (0.2LSCO) thin films were prepared via the RF sputtering method to fabricate thin-film thermocouples (TFTCs), and post-annealing processes were employed to optimize their properties to sense high temperatures. The XRD patterns of the 0.2LSCO thin films showed a pure phase, and their crystallinities increased with the post-annealing temperature from 800 °C to 1000 °C, while some impurity phases of Cr2O3 and SrCr2O7 were observed above 1000 °C. The surface images indicated that the grain size increased first and then decreased, and the maximum size was 0.71 μm at 1100 °C. The cross-sectional images showed that the thickness of the 0.2LSCO thin films decreased significantly above 1000 °C, which was mainly due to the evaporation of Sr2+ and Cr3+. At the same time, the maximum conductivity was achieved for the film annealed at 1000 °C, which was 6.25 × 10−2 S/cm. When the thin films post-annealed at different temperatures were coupled with Pt reference electrodes to form TFTCs, the trend of output voltage to first increase and then decrease was observed, and the maximum average Seebeck coefficient of 167.8 µV/°C was obtained for the 0.2LSCO thin film post-annealed at 1100 °C. Through post-annealing optimization, the best post-annealing temperature was 1000 °C, which made the 0.2LSCO thin film more stable to monitor the temperatures of turbine engines for a long period of time.

Formability and Process Conditions of Magnesium Alloy Sheets

2005 ◽  
Vol 488-489 ◽  
pp. 453-456 ◽  
Author(s):  
Shi Hong Zhang ◽  
Yong Chao Xu ◽  
G. Palumbo ◽  
S. Pinto ◽  
Luigi Tricarico ◽  
...  
Keyword(s):  
Deep Drawing ◽  
Tensile Tests ◽  
Process Conditions ◽  
Drawing Ratio ◽  
Temperature Range ◽  
Fine Grained ◽  
Axial Tensile ◽  
Die Surface ◽  
Lower Temperature Range ◽  
Lower Temperature

Comparing the formability with each other, extrusion and various rolling experiments were carried out to make fine-grained AZ31 Mg sheets, and uni-axial tensile tests were carried out at different strain rates and temperatures to investigate the effect of different variables. A warm deep drawing tool setup with heating elements, which were distributed under the die surface and inside the blank holder, was designed and manufactured, and deep drawing was performed. Extruded Mg alloy AZ31 sheets exhibit the best deep drawing ability when working in the temperature range 250-350°C. Extruded and rolled sheets of 0.8 mm thick were also deep drawn in the lower temperature range 105-170°C，showing good formability and reaching a Limit Drawing Ratio up to 2.6 at 170°C for rolled sheets. At last, a sheet cup 0.4 mm thick was deep drawn successfully at 170 °C.

scholarly journals Intraspecific Variation in Maximum Ingested Food Size and Body Mass in Varecia rubra and Propithecus coquereli

2011 ◽  
Vol 2011 ◽  
pp. 1-8 ◽  
Author(s):  
Adam Hartstone-Rose ◽  
Jonathan M. G. Perry
Keyword(s):  
Body Size ◽  
Body Mass ◽  
Individual Variation ◽  
Size Variation ◽  
Maximum Size ◽  
Least Squares Regression ◽  
Scaling Relationship ◽  
Varecia Rubra ◽  
Food Size ◽  
The Relationship

In a recent study, we quantified the scaling of ingested food size (Vb )—the maximum size at which an animal consistently ingests food whole—and found that Vb scaled isometrically between species of captive strepsirrhines. The current study examines the relationship between Vb and body size within species with a focus on the frugivorous Varecia rubra and the folivorous Propithecus coquereli. We found no overlap in Vb between the species (all V. rubra ingested larger pieces of food relative to those eaten by P. coquereli), and least-squares regression of Vb and three different measures of body mass showed no scaling relationship within each species. We believe that this lack of relationship results from the relatively narrow intraspecific body size variation and seemingly patternless individual variation in Vb within species and take this study as further evidence that general scaling questions are best examined interspecifically rather than intraspecifically.

scholarly journals Effects of light intensity and temperature on Cylindrospermopsis raciborskii (Cyanobacteria) with straight and coiled trichomes: growth rate and morphology

2012 ◽  
Vol 72 (2) ◽  
pp. 343-351 ◽  
Author(s):  
MC. Bittencourt-Oliveira ◽  
B. Buch ◽  
TC. Hereman ◽  
JDT. Arruda-Neto ◽  
AN. Moura ◽  
...  
Keyword(s):  
Growth Rate ◽  
Light Intensity ◽  
Morphological Changes ◽  
Population Control ◽  
Distinct Species ◽  
Cylindrospermopsis Raciborskii ◽  
Climatic Chamber ◽  
Light Intensities ◽  
Different Temperatures ◽  
Lower Temperature

Cylindrospermopsis raciborskii (Woloszynska) Seenayya et Subba Raju (Ordem Nostocales) is one of the most troublesome bloom-forming species in Brazil. Understanding the population dynamics of the different morphotypes of C. raciborskii (straight and coiled) could assist in the prediction of favourable conditions for the proliferation of this potentially toxin-producing species. The aim of the present study was to assess the effects of two different light intensities and temperatures on the growth rate and morphology of the trichomes of the straight and coiled morphotypes. For such, two non-toxin producing strains of C. raciborskii were used - one with a coiled trichome (ITEP31) and another with a straight trichome (ITEP28). The strains were cultured in BG-11 medium in a climatic chamber under controlled conditions. Two light intensities (30 and 90 µmol.m-2.s-1 ) were combined at temperatures of 21 and 31 °C and the growth rate and morphological changes were analysed. The morphotypes responded differently to the different temperatures and light intensities. Both strains exhibited faster growth velocities when submitted to higher light intensity and temperature. The lower temperature and higher luminosity hampered the development of both strains. Variations in cellular morphology and an absence of akinetes in both strains were related to the lower temperature (21 °C). The coiled morphotype demonstrated considerable phenotype plasticity, changing the morphology of trichome throughout its growth curve. Although molecular analysis does not sustain the separation of the morphotypes as distinct species, their different eco-physiological responses should be considered further knowledge of extreme importance for the population control of these potentially toxic organisms.

scholarly journals Creep behaviour and life assessment of a cast nickel – base superalloy MAR – M247

2019 ◽  
Vol 38 (2019) ◽  
pp. 590-600
Author(s):  
Marie Kvapilova ◽  
Jiri Dvorak ◽  
Petr Kral ◽  
Karel Hrbacek ◽  
Vaclav Sklenicka
Keyword(s):  
Creep Behaviour ◽  
Life Assessment ◽  
Dislocation Creep ◽  
Nickel Base Superalloy ◽  
Creep Characteristics ◽  
Different Temperatures ◽  
High Temperature Components ◽  
Lower Temperature ◽  
Nickel Base ◽  
Different Grain Size

AbstractThe cast nickel-base MAR-M247 superalloy has been widely used for high-temperature components. In this work, the creep behaviour of two alternates of MAR-M247 superalloy with different grain size processed at different temperatures of casting are compared. Under the creep testing conditions used in this study, only negligible differences of creep behaviour of the alternate alloys were found and the evaluated creep characteristics correspond to the power-law or dislocation creep. The microstructure of the alloys consists of a𝛾matrix with a eutectic,𝛾'strengthening cubic precipitates, and M6C and M23C6carbides. Increasing the temperature induces the dissolution of some M23C6carbides. Fractures of both variants of alloys exhibit a more ductile character at higher temperatures, while at lower temperature a mixture of brittle and ductile fracture modes was observed, which changes the creep fracture ductility.

A Fluidity-Temperature Relationship for Liquids

1973 ◽  
Vol 95 (2) ◽  
pp. 236-241
Author(s):  
T. F. Ford ◽  
C. R. Singleterry
Keyword(s):  
Interpolation Formula ◽  
Absolute Temperature ◽  
Temperature Relationship ◽  
Organic Liquids ◽  
Low Viscosity ◽  
Linear Relationships ◽  
Temperature Ranges ◽  
The Absolute ◽  
The Relationship

Many relationships between viscosity or its reciprocal, fluidity, and temperature have been proposed for liquids. None except the empirically modified ASTM chart have proven satisfactory over extended temperature ranges. We here note that by plotting the kinematic fluidity (φkin) against the square of the absolute temperature (deg K2) we obtain linear relationships for a wide variety of organic liquids at kinematic viscosities less than about 1.67 centistokes (or fluidities above about 0.60 reciprocal centistokes). The generality of the relationship appears to justify the use of the equation, φkin=a+bT2, as an interpolation formula for organic liquids in the low viscosity region.

Sign in / Sign up

Export Citation Format

Share Document