Efficacy of Experimental Mouth Rinses on Caries-Related Biofilms in vitro

This study assessed the efficacy of tin and Polyethylenglycol (PEG-3) tallow aminopropylamine in different concentrations on Streptococcus mutans (S. mutans) biofilms to establish a new screening process for different antimicrobial agents and to gain more information on the antibacterial effects of these agents on cariogenic biofilms. Isothermal microcalorimetry (IMC) was used to determine differences in two growth parameters: lag time and growth rate; additionally, reduction in active biofilms was calculated. Experimental mouth rinses with 400 and 800 ppm tin derived from stannous fluoride (SnF2) revealed results (43.4 and 49.9% active biofilm reduction, respectively) similar to meridol mouth rinse (400 ppm tin combined with 1,567 ppm PEG-3 tallow aminopropylamine; 55.3% active biofilm reduction) (p > 0.05), while no growth of S. mutans biofilms was detected during 72 h for samples treated with an experimental rinse containing 1,600 ppm tin (100% active biofilm reduction). Only the highest concentration (12,536 ppm) of rinses containing PEG-3 tallow aminopropylamine derived from amine fluoride (AmF) revealed comparable results to meridol (57.5% reduction in active biofilm). Lower concentrations of PEG-3 tallow aminopropylamine showed reductions of 16.9% for 3,134 ppm and 33.5% for 6,268 ppm. Maximum growth rate was significantly lower for all the samples containing SnF2 than for the samples containing control biofilms (p < 0.05); no differences were found between the control and all the PEG-3 tallow aminopropylamine (p > 0.05). The growth parameters showed high reproducibility rates within the treated groups of biofilms and for the controls; thus, the screening method provided reliable results.

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Sex-specific growth of nestlings of the Whiskered Tern Chlidonias hybrida, a species with sexual size dimorphism and female brood desertion

Journal of Ornithology ◽

10.1007/s10336-021-01911-y ◽

2021 ◽

Author(s):

Agata Banach ◽

Grzegorz Neubauer ◽

Adam Flis ◽

Mateusz Ledwoń

Keyword(s):

Growth Rate ◽

Body Mass ◽

Sexual Size Dimorphism ◽

Growth Parameters ◽

Maximum Growth ◽

Maximum Growth Rate ◽

Head Length ◽

Whiskered Tern ◽

Total Head ◽

Chlidonias Hybrida

AbstractThe growth of a nestling during the first few weeks after hatching is crucial for its further life and is sensitive to the conditions experienced during this period. Among species exhibiting Sexual Size Dimorphism (SSD), one of the most important factors influencing growth parameters is the sex of the hatchlings. In this study, we tested whether sex and other factors (hatching date, egg volume, brood size and sex ratio in the brood) were related to sex on growth parameters in Whiskered Tern (Chlidonias hybrida) chicks. In this species, males are 3%–10% larger than females when adult. At hatching, only the total head length was greater in males than females, but values close to fledging were greater for most of the measured parameters (3%—tarsus, 4%—total head length, 13%—body mass). Moreover, the maximum body mass growth rate was higher in males but females entered the rapid growth phase somewhat earlier and achieved the final total head length sooner. Nestling growth was also significantly correlated with brood size and hatching date, though mostly negatively (e.g. lower tarsus and total head length asymptote, lower maximum growth rate and growth rate constant of total head length in bigger and later clutches). The occurrence of SSD during the nestling period and higher maximum growth rate of body mass in males indicates that the costs of raising sons may be higher than of raising daughters. However, we did not find evidence of either sex-biased nestling mortality or skewed sex ratio.

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Comparison of Enrichment Broths for the Recovery of Healthy and Heat-Injured Salmonella Typhimurium on Raw Duck Wings

Journal of Food Protection ◽

10.4315/0362-028x.jfp-13-041 ◽

2013 ◽

Vol 76 (11) ◽

pp. 1963-1968 ◽

Cited By ~ 12

Author(s):

QIANWANG ZHENG ◽

CAROLINE BUSTANDI ◽

YISHAN YANG ◽

KEITH R. SCHNEIDER ◽

HYUN-GYUN YUK

Keyword(s):

Growth Rate ◽

Salmonella Typhimurium ◽

Doubling Time ◽

Growth Parameters ◽

False Negative ◽

Maximum Growth ◽

Maximum Growth Rate ◽

Detection Methods ◽

Lag Phase ◽

Peptone Water

This study was performed to optimize Salmonella Typhimurium recovery from raw duck wings with five nonselective broths (buffered peptone water, tryptic soy broth, lactose broth, universal preenrichment broth, nutrient broth) and four selective broths (selenite broth, BAX System MP media [MP], Salmonella AD media [AD], ONE broth-Salmonella [OB]). Healthy or heat-injured (50 and 85% injury) cells were inoculated at a level of 102, 101, or 100 CFU/25 g on raw duck wings. Growth was modeled using DMfit with four growth parameters: lag-phase duration, maximum growth rate, doubling time, and maximum population density. Most enrichments were able to recover Salmonella Typhimurium to greater than 6 log CFU/ml. AD, MP, and OB had significantly (P < 0.05) higher maximum growth rate (0.9 to 1.0/h) and lower doubling time (0.7 to 0.8 h). Buffered peptone water, AD, MP, and OB recovered healthy and 50%-injured cells at low inoculum levels to more than 6.0 log CFU/ml; OB achieved the greatest recovery (7.6 and 7.9 log CFU/ml), following 24 h of incubation. The 85%-injured cells at 100 and 101 CFU/25 g, however, were only recovered in OB, reaching 7.3 and 7.5 log CFU/ml, respectively. These results suggest that OB may be an appropriate enrichment broth for the recovery of Salmonella Typhimurium from raw duck wings in standard diagnostic tests or other rapid detection methods, to avoid false-negative results.

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A model of individual variation in the food conversion efficiency and other growth parameters of grazing beef cattle in the tropics

Australian Journal of Agricultural Research ◽

10.1071/ar9880943 ◽

1988 ◽

Vol 39 (5) ◽

pp. 943 ◽

Cited By ~ 1

Author(s):

S Saithanoo ◽

ME Goddard

Keyword(s):

Growth Rate ◽

Heat Stress ◽

Genetic Correlation ◽

Individual Variation ◽

Growth Parameters ◽

Maximum Growth ◽

Maximum Growth Rate ◽

Tropical Pastures ◽

Maintenance Requirement ◽

Mature Size

Methods to genetically improve gross food efficiency (GFE) in cattle usually rely on a high genetic correlation between GFE and growth rate. Estimating this genetic correlation for cattle grazing tropical pastures is extremely difficult, so a model of individual variation in growth has been developed based on component traits which are known to affect growth rate. The model assumes that there is individual variation in mature size, maintenance requirement, intake to maintenance ratio, and susceptibility to heat stress and to tick and worm infestation. Nutritional level is assumed to interact with maintenance requirement, so that under good nutrition a high level of maintenance requirement maximises growth rate, whereas under a low level of nutrition a low maintenance requirement leads to maximum growth rate. The model predicts that in the presence of environmental stress the correlation between growth rate and mature size is only about 0.5, and there is no correlation between mature size and GFE. Growth rate and GFE are correlated with resistance to parasite and heat stress and to intake:maintenance ratio. Consequently growth rate and GFE are highly correlated, especially under stressful environmental conditions. The model predicts that growth rate in one environment will be highly genetically correlated with growth rate in other similar environments.

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Maturation of White Sucker, Catostomus commersoni, Populations in Ontario

Canadian Journal of Fisheries and Aquatic Sciences ◽

10.1139/f94-209 ◽

1994 ◽

Vol 51 (9) ◽

pp. 2066-2076 ◽

Cited By ~ 18

Author(s):

Y. Chen ◽

H. H. Harvey

Keyword(s):

Growth Rate ◽

Robust Regression ◽

Growth Parameters ◽

Maximum Growth ◽

Maximum Growth Rate ◽

Population Variation ◽

Linear Regression Method ◽

White Sucker ◽

Catostomus Commersoni ◽

Fitting Length

White sucker, Catostomus commersoni, were sampled from 13 Ontario lakes. Two growth parameters (growth rate in length as dL/dt at age t0 and age at maximum growth rate in weight as dW/dt) were estimated by fitting length- and weight-at-age data to the two reparameterized von Bertalanffy growth functions for each of 13 populations. Two maturation parameters (length and age at 50% maturity, ML and MA) were estimated using the linear regression method for both sexes. Two regression approaches were used in analyzing experimental data: a traditional geometric means (GM) method and a two-step procedure of robust regression analysis which includes applying the least median squares method to identify possible outliers and applying the GM method to data exclusive of the defined outliers. Great among-population variation in the estimated growth and maturation parameters was observed for both female and male white sucker. White sucker growing faster at young ages tended to mature earlier. High population density might result in white sucker having slower growth rates in their earlier ages and larger MA's. This study indicated that maturation of white sucker is food dependent, and early growth rate is an important factor in determining the timing of maturity.

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A note on growth curves of rabbit lines selected on growth rate or litter size

Animal Science ◽

10.1017/s000335610000698x ◽

1993 ◽

Vol 57 (2) ◽

pp. 332-334 ◽

Cited By ~ 13

Author(s):

A. Blasco ◽

E. Gómez

Keyword(s):

Growth Rate ◽

Litter Size ◽

Growth Curves ◽

Live Weight ◽

Maximum Growth ◽

Maximum Growth Rate ◽

Standard Errors ◽

Adult Weight ◽

Weight Growth ◽

Using Data

Two synthetic lines of rabbits were used in the experiment. Line V, selected on litter size, and line R, selected on growth rate. Ninety-six animals were randomly collected from 48 litters, taking a male and a female each time. Richards and Gompertz growth curves were fitted. Sexual dimorphism appeared in the line V but not in the R. Values for b and k were similar in all curves. Maximum growth rate took place in weeks 7 to 8. A break due to weaning could be observed in weeks 4 to 5. Although there is a remarkable similarity of the values of all the parameters using data from the first 20 weeks only, the higher standard errors on adult weight would make 30 weeks the preferable time to take data for live-weight growth curves.

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Reassessment of Maximum Growth Rates for C3 and C4 Crops

Experimental Agriculture ◽

10.1017/s0014479700008255 ◽

1978 ◽

Vol 14 (1) ◽

pp. 1-5 ◽

Cited By ~ 129

Author(s):

J. L. Monteith

Keyword(s):

Growth Rate ◽

Growth Rates ◽

Growing Season ◽

Maximum Growth ◽

Maximum Growth Rate ◽

Crop Growth ◽

Close Inspection ◽

Similar Difference ◽

Photosynthetic Efficiencies

SUMMARYFigures for maximum crop growth rates, reviewed by Gifford (1974), suggest that the productivity of C3 and C4 species is almost indistinguishable. However, close inspection of these figures at source and correspondence with several authors revealed a number of errors. When all unreliable figures were discarded, the maximum growth rate for C3 stands fell in the range 34–39 g m−2 d−1 compared with 50–54 g m−2 d−1 for C4 stands. Maximum growth rates averaged over the whole growing season showed a similar difference: 13 g m−2 d−1 for C3 and 22 g m−2 d−1 for C4. These figures correspond to photosynthetic efficiencies of approximately 1·4 and 2·0%.

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Interpretation of Experimental Data with Regard to the Activated Sludge Model No.1 and Calibration of the Model for Municipal Wastewater Treatment Plants

Water Science & Technology ◽

10.2166/wst.1992.0121 ◽

1992 ◽

Vol 25 (6) ◽

pp. 167-183 ◽

Cited By ~ 16

Author(s):

H. Siegrist ◽

M. Tschui

Keyword(s):

Experimental Data ◽

Growth Rate ◽

Activated Sludge ◽

Municipal Wastewater ◽

Wastewater Treatment Plants ◽

Treatment Plant ◽

Maximum Growth ◽

Maximum Growth Rate ◽

Municipal Wastewater Treatment ◽

Activated Sludge Model

The wastewater of the municipal treatment plants Zürich-Werdhölzli (350000 population equivalents), Zürich-Glatt (110000), and Wattwil (20000) have been characterized with regard to the activated sludge model Nr.1 of the IAWPRC task group. Zürich-Glatt and Wattwil are partly nitrifying treatment plants and Zürich-Werdhölzli is fully nitrifying. The mixing characteristics of the aeration tanks at Werdhölzli and Glatt were determined with sodium bromide as a tracer. The experimental data were used to calibrate hydrolysis, heterotrophic growth and nitrification. Problems arising by calibrating hydrolysis of the paniculate material and by measuring oxygen consumption of heterotrophic and nitrifying microorganisms are discussed. For hydrolysis the experimental data indicate first-order kinetics. For nitrification a maximum growth rate of 0.40±0.07 d−1, corresponding to an observed growth rate of 0.26±0.04 d−1 was calculated at 10°C. The half velocity constant found for 12 and 20°C was 2 mg NH4-N/l. The calibrated model was verified with experimental dam of me Zürich-Werdhölzli treatment plant during ammonia shock load.

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Factors which influence the timing of maximum growth rate of the head in low birthweight infants.

Archives of Disease in Childhood ◽

10.1136/adc.52.2.113 ◽

1977 ◽

Vol 52 (2) ◽

pp. 113-117 ◽

Cited By ~ 8

Author(s):

M Fujimura

Keyword(s):

Growth Rate ◽

Low Birthweight ◽

Maximum Growth ◽

Maximum Growth Rate

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Dietary Protein Requirements of Fishes — A Reassessment

Canadian Journal of Fisheries and Aquatic Sciences ◽

10.1139/f87-244 ◽

1987 ◽

Vol 44 (11) ◽

pp. 1995-2001 ◽

Cited By ~ 52

Author(s):

Stephen H. Bowen

Keyword(s):

Growth Rate ◽

Dietary Protein ◽

Protein Concentration ◽

Trophic Ecology ◽

Maximum Growth ◽

Maximum Growth Rate ◽

Intake Rate ◽

Protein Requirement ◽

Fish Physiology ◽

Protein Retention

It is widely believed that fishes require more dietary protein than other vertebrates. Many aspects of fish physiology, nutrition, and trophic ecology have been interpreted within the context of this high protein requirement. Here, fishes are compared with terrestrial homeotherms in terms of (1) protein requirement for maintenance, (2) relative protein concentration in the diet required for maximum growth rate, (3) protein intake rate required for maximum growth rate, (4) efficiency of protein retention in growth, and (5) weight of growth achieved per weight of protein ingested. The two animal groups compared differ only in relative protein concentration in the diet required for maximum growth rate. This difference is explained in terms of homeotherms' greater requirement for energy and does not reflect absolute differences in protein requirement. The remaining measures of protein requirement suggest that fishes and terrestrial homeotherms are remarkably similar in their use of protein as a nutritional resource. Reinterpretation of the role of protein in fish physiology, nutrition, and trophic ecology is perhaps in order.

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