Minimum Growth Rate Research Articles

Evaluation of Hemato-Biochemical Parameters, Body and Organ Weight and Reproductive Profile Changes in Response to Receiving Different Levels of Indomie Noodles in Albino Rats

The Indomie noodles are an instant noodle sold dried in packets or cups. The noodles are quick and easy to make and can be eaten as a snack or part of the main meal. This study was designed to examine the possible effect of different levels of Indomie noodles on the hematological biochemical profile, organosomatic index and male fertility indices in healthy adult albino rats. In an experimental study, twenty male rats of average weight 115 g (divided into four groups) and twenty female rats of average weight 100 g (divided into four groups). Each group consists of five rats. Group A is the control group and was fed with standard rat feed. In contrast, groups B, C and D were supplied with 25 %, 50 % and 75 % Indomie instant noodles cooked and spiced with the seasoning. The administration was carried out for 8 w. The result showed that the body weight, expressed as growth rate, showed that rats exposed to the 75 % Indomie noodle formulated diets had significantly minimum growth rates than controls and other two different groups. There was a significant increase (p<0.05) in the organosomatic index (kidney, liver, brain and testes) of rats fed on a diet containing 75 % Indomie noodles. There was a significant (p<0.05) increase in lymphocytes percentage, with a decrease in monocytes and granulocyte percentages compared to the control group. Red blood cell indices examination showed a reduction in mean cell volume, mean cell hemoglobin and mean cell hemoglobin concentration value. A diet containing 75 % Indomie noodles appeared to the highest significant decrease in total serum protein and serum uric acid with a significant increase of alkaline phosphatase and blood urea at 25 %, 50 % and 75 % in comparison to the control group. However, aspartate aminotransferase results show a significant difference at 75 % compared to 0 %. On the other, evaluation of various sperm parameters showed there was a significant reduction in sperm concentration, motility and viability between treated groups in comparison to the untreated group in response to an increase in the percent of Indomie noodles in the diet and their plasma testosterone levels of the treated groups decreased insignificantly than those of the control group.

Modulational instability of the coupled waves between fast magnetosonic wave and slow Alfvén wave in the laser–plasma interaction

By performing modulational instability analysis of the the nonlinear coupled dimensionless equations between a fast magnetosonic wave (FMSW) propagating obliquely with the magnetic field and a low-frequency slow Alfvén wave (SAW), we obtain the dispersion relation of the perturbation wave. The growth rate of the perturbation wave is obtained. It is found that the growth rate increases as background magnetic field increases, which is in agreement with that reported by Tiwary et al (2016 Phys. Plasmas 23 122307). A critical perturbation wave number is found. When the perturbation wave number is greater than or equal to the critical value, the growth rate is positive and it increases as the perturbation wave number increases, while the wave is stable. The maximum growth rate is reached when the frequency of the FMSW is half of the ion cyclotron frequency. The minimum growth rate is reached when the propagation direction of the perturbation wave is the same as that of the FMSW.

Explanation of the Principle of Minimum Growth Rate in Multiplicatively Interacting Stochastic Process

Multiplicatively interacting stochastic process consists of many particles having their own values and they do binary interactions to exchange their values multiplicatively. It is known that the pr...

On the Formation Mechanism of the Seasonal Persistence Barrier

AbstractThe mechanism of the seasonal persistence barrier (SPB) is studied in the framework of an autoregressive (AR) model. In contrast to the seasonal variance, whose minimum is modulated mainly by the minimum growth rate or noise forcing, the SPB is caused primarily by the declining growth rate or increasing noise forcing, instead of the minimum/maximum of the growth rate or noise forcing. In other words, the SPB is caused by the declining signal-to-noise ratio (SNR) rather than the weakest SNR. In a weakly damped system, the phase of the SPB is delayed from that of declining SNR by about a season. The mechanism is further applied to explain the observed SST variability in the tropical and North Pacific. For the tropical Pacific, the spring SPB could be caused by the decreasing growth rate from September to March and weak annual mean damping rate, instead of the minimum growth rate in spring. Over the North Pacific, the increasing noise forcing from March to June may lead to the summer SPB. Our mechanism provides a null hypothesis for understanding the SPB of climate variability.

Analyzing the ignition differences between conventional spark discharges and nanosecond-pulsed high-frequency discharges

New methods of energy deposition using nanosecond-pulsed high-frequency discharges (NPHFD) have shown promise in igniting fuel-lean conditions. This work compared an NPHFD ignition system to a conventional, capacitive discharge system in a flowing environment under matching total energy and average power conditions. The results showed that, in every case, matching the average power and deposited energy between the two systems resulted in similar trends in kernel radius growth, time to minimum growth rate, and kernel radius at which minimum growth rate occurs. These results were used as a baseline for comparison for the lower average power NPHFD test conditions. Decreasing the power of the NPHFD system while maintaining the total energy deposited allowed kernel growth to be aided by flow advection, resulting in a ∼38% increase in the streamwise radius as compared to the baseline. The larger kernel size comes at the expense of the kernel taking ∼20% longer to transition to a self-propagating flame that occurs at a radius that is ∼72% larger than the respective values for the baseline condition. This behavior is due to the long duration of the discharge and the low energy density per unit volume in the fluid, respectively. The benefit of the larger kernel size comes at the cost of reliability. Therefore, in combustor conditions with strong external quenching physics, depositing the most energy in the shortest time will be optimal. Conversely, for kernels in the presence of mild turbulence, the average power can be decreased, and flow advection can be utilized to grow the kernel over a longer duration without risk of extinction.

The almost sure semicircle law for random band matrices with dependent entries

We analyze the empirical spectral distribution of random periodic band matrices with correlated entries. The correlation structure we study was first introduced in Hochstättler et al. (2015) by Hochstättler, Kirsch and Warzel, who named their setup almost uncorrelated and showed convergence to the semicircle distribution in probability. We strengthen their results which turn out to be also valid almost surely. Moreover, we extend them to band matrices. Sufficient conditions for convergence to the semicircle law both in probability and almost surely are provided. In contrast to convergence in probability, almost sure convergence seems to require a minimal growth rate for the bandwidth in the correlated case. Examples that fit our general setup include Curie–Weiss distributed, correlated Gaussian, and as a special case, independent entries.

A New Formulation of a Criterion for the Minimal Logarithmic Growth Rate

We obtain a new formulation of a criterion for the minimal logarithmic growth rate for an arbitrary finite set with a given set of operations. It turns out that a finite set with operations has the minimal logarithmic growth rate if and only if the set of operations is not entirely contained in any of the precomplete (maximal) classes other than the classes preserving subsets and the classes of functions that preserve predicates given by permutations decomposable into cycles of the same prime length.

On classes of functions of many-valued logic with minimal logarithmic growth rate

AbstractWe obtain a criterion for the minimal logarithmic growth rate for an arbitrary set with a given set of operations defined on it, i.e., we describe all finite sets A with operations on them such that the growth rate differs by at most a constant from the logarithmic growth rate to base ∣A∣.

Ontogeny of the trilobite Elrathia kingii (Meek) and comparison of growth rates between Elrathia kingii and Aulacopleura koninckii (Barrande)

AbstractTrilobites offer almost unparalleled insight into the growth and development of fossil ecdysozoans. Here I use newly collected material of Elrathia kingii (Meek) to estimate growth rates and describe shape change over the ontogeny of E. kingii. Well‐preserved, articulated specimens from all post‐embryonic stages were collected from a 1.5 m interval of the upper Wheeler Formation (Miaolingian Series, Cambrian) in western Utah (USA), and size and landmark‐based shape data were digitized from photographs. Growth rates were estimated and compared with previously published data on the Silurian trilobite, Aulacopleura koninckii (Barrande). Like A. koninckii, the cephalic growth rate in E. kingii was constant and of similar magnitude to the minimum growth rate along the trunk, and growth rates in the trunk were lower during the holaspid (‘adult’) period than during the meraspid (‘juvenile’) period. However, body length at the onset of meraspis was smaller, the growth gradient along the trunk during meraspis was shallower, and the terminal number of thoracic tergites was smaller in E. kingii than in A. koninckii. Despite these differences, these two species had similar maximum body lengths, because higher overall growth rates in E. kingii compensated for other differences. The rate of cephalic shape change in E. kingii decreased at the transition from meraspis to holaspis, while the pygidium became more morphologically distinct from the thorax during holaspis. I also provide an emended diagnosis for E. kingii, descriptions of the ontogeny and ventral morphology, and evidence that E. kingii holaspids had an invariant number of tergites.

The fluctuation impact of human mobility on the influenza transmission

In this paper, we investigate the fluctuation impact of human mobility on influenza transmissions through a stochastic differential equation (SDE) model with environmental driving forces through both analytical and numerical analysis. We define a stochastic basic reproduction number R0s through a detailed process of calculations for the SDE model. Through R0s, the conditions for the stochastic extinction and persistence of the influenza disease are identified. We show that an epidemic stationary distribution exists in the case of persistence of influenza disease by constructing an appropriate Lyapunov function. We find that: (1) large environment fluctuations can suppress the outbreak of the influenza; (2) R0s determines stochastic distributions; (3) proper noise perturbations can be beneficial to control the spread of the influenza; (4) high economic capability can prohibit the influenza outbreaks; (5) seemingly irregular but appropriate human mobility response can significantly reduce the epidemic prevalence; (6) the positivity of the minimum intrinsic growth rate of human mobility density is the key factor of the stochastic persistence of the influenza disease.

Effects of Loading Spectra on High pH Crack Growth Behavior of X65 Pipeline Steel

The effects of mechanical factors on crack growth behavior during the second stage of high pH stress corrosion cracking in pipeline steel were investigated by applying several loading scenarios on compact tension (CT) specimens. The main mechanism for stage 2 of intergranular crack propagation is anodic dissolution ahead of the crack tip which is highly dependent on crack-tip strain rate. The maximum and minimum crack growth rates were 3 × 10−7 mm/s and 1 × 10−7 mm/s, respectively. It was observed that several factors such as mean stress intensity factor, amplitude, and frequency of loading cycles determine the crack-tip strain rate. Low R-ratio cycles, particularly high-frequency ones, enhance secondary crack initiation, and crack coalescence on the free surface. This mechanism accelerates crack advance on the free surface which is accompanied with an increase in mechanical driving force for crack propagation in the thickness direction. These findings have implications for pipeline operators and could be used to increase the lifespan of the cracked pipelines at stage 2. For those pipelines, any loading condition that increases the strain rate ahead of the crack tip enhances anodic dissolution and is detrimental. Additionally, secondary crack initiation and coalescence could be minimized by avoiding internal pressure fluctuation, particularly rapid large pressure fluctuations.

Convergence and growth – conflicting goals of economics policy – A case study of Georgia

Abstract Over the years, it has been the subject of discussions whether efficiency-oriented interventions contribute to an equity distribution of wealth across regions and whether equity orientation is a source of inefficiency. While efficiency refers to the maximization of growth in the national economy, convergence-oriented policy is focused on equalizing the level of development at interregional level. The case of Georgia was studied as a developing country facing various challenges in terms of economic growth and regional divergence. This article provides an overview of the economic development trends taking place in the regions of Georgia and reveals the high level of divergence within the country. A logarithmic model was created and used to run simulations to predict the possible results of convergence-oriented policy in Georgia. In order to make the forecast we estimated GDP per capita and average growth rates in all the Georgian regions. Use of the model allowed us to answer two main questions: (1) If the last 5 and 10 year average growth rates are maintained, how long will it take for the poorest region to converge to the wealthiest one? (2) What should be the minimum growth rate in the poorest region for the upcoming 5, 10 and 20 years in order to converge to the wealthiest capital? Results of the calculations showed that convergence between regions can only be achieved by slowing down economic growth in relatively wealthier regions and by focusing on the development of the poorest ones. The results of the study revealed that the convergence process will be faster for the regions with medium or big cities and growth centres. Therefore, creating competitive growth centres would be a reasonable regional policy objective to promote fast economic growth and future convergence without redirecting the growth process from more developed areas to lagging ones.

Resistance Evolution Against Antimicrobial Peptides in Staphylococcus aureus Alters Pharmacodynamics Beyond the MIC.

Antimicrobial peptides (AMPs) have been proposed as a promising class of new antimicrobials partly because they are less susceptible to bacterial resistance evolution. This is possibly caused by their mode of action but also by their pharmacodynamic characteristics, which differ significantly from conventional antibiotics. Although pharmacodynamics of antibiotic resistant strains have been studied, such data are lacking for AMP resistant strains. Here, we investigated if the pharmacodynamics of the Gram-positive human pathogen Staphylococcous aureus evolve under antimicrobial peptide selection. Interestingly, the Hill coefficient (kappa κ) evolves together with the minimum inhibition concentration (MIC). Except for one genotype, strains harboring mutations in menF and atl, all mutants had higher kappa than the non-selected sensitive controls. Higher κ results in steeper pharmacodynamic curve and, importantly, in a narrower mutant selection window. S. aureus selected for resistance to melittin displayed cross resistant against pexiganan and had as steep pharmacodynamic curves (high κ) as pexiganan-selected lines. By contrast, the pexiganan-sensitive tenecin-selected lines displayed lower κ. Taken together, our data demonstrate that pharmacodynamic parameters are not fixed traits of particular drug/strain interactions but actually evolve under drug treatment. The contribution of factors such as κ and the maximum and minimum growth rates on the dynamics and probability of resistance evolution are open questions that require urgent attention.

Tropical Tree Growth and Longevity: Validation of Growth Simulation, a Bootstrapping Model

ABSTRACT Growth Simulation, an analytical modeling technique, has been increasingly used in ecological studies and practical forestry applications where dendrochronology is not applicable. The technique uses randomly sampled diameter increments from tagged trees over a known time interval to assemble a statistical sample of lifetime growth trajectories. We carried out a validation of Growth Simulation using a temperate species in order to compare indirect model outputs with direct tree ring analysis. Rings were measured on sample disks cut from 55 pine branches ranging in age from 8–36 years. Assessments included lifetime growth rates, growth rate with respect to diameter and age, periodic annual increment (PAI), cross-referencing of rings by date, and autocorrelation of growth over successive periods. Tree ring analysis and Growth Simulation showed close correspondence for all parameters tested (maximum, median, and minimum growth rates; longevity estimates). Growth Simulation is found to be a robust and informative technique for studies of tropical tree growth, and is especially useful where analysis of tree rings is not feasible or when bootstrapping analysis of ring data is of interest.

Mountain-to-sea ecological-resource management: Forested watersheds, coastal aquifers, and groundwater dependent ecosystems

Improving the understanding of connections spanning from mountain to sea and integrating those connections into decision models have been increasingly recognized as key to effective coastal resource management. In this paper, we aim to improve our understanding of the relative importance of linkages between a forested watershed, a coastal groundwater aquifer, and a nearshore marine groundwater-dependent ecosystem (GDE) using a dynamic groundwater optimization framework and simple ecosystem equations. Data from the Kīholo aquifer on the Kona Coast of Hawai‘i Island are used to numerically illustrate optimal joint management strategies and test the sensitivity of those strategies to variations in physical and behavioral parameter values. We find that for a plausible range of watershed management costs, protecting part of the recharge capture area is always optimal. Without watershed protection, maintaining a safe minimum standard growth rate for a GDE-dependent marine indicator species, reduces net present value non-trivially, but optimal investment in watershed conservation offsets that potential reduction by 75 %. In general, we find that optimal watershed management and groundwater pumping are most sensitive to changes in water demand growth and parameters that describe nearshore salinity.

Ultra-slow growth rate: Accurate control of the thickness of porous anodic aluminum oxide films

Porous anodic aluminum oxide (PAAO) films have attracted widespread attention because they can be used as porous templates for the preparation of various nanomaterials. However, there are still some challenges. For example, although fine control of the thickness of AAO films is generally quite easy to achieve, it is difficult to control the thickness of extremely thin films (e.g. <1 µm). This is important for practical applications where accurate control of film thickness is necessary. In the present work, PAAO films have been prepared in an electrolyte composed of a mixture of ethanol and oxalic acid under 40–50 V (at −20 to 0 °C), attaining a minimum growth rate (νa) of ~1.4 nm min−1 (at −20 °C). The influence of anodization conditions on νa, the regularity of structural cells, and the interpore distance has been studied in detail. The results show that νa can be reduced effectively by using an extremely low anodization temperature. Ultra-thin PAAO films with precisely controlled thicknesses have been fabricated using this approach.

Damage potential of Tribolium castaneum (Herbst) (Coleoptera: Tenebrionidae) on wheat grains stored in hermetic and non-hermetic storage bags

Post-harvest storage of wheat in grain storage bags is commonly adopted practice in many developing countries, which offers a viable chemical-free approach to control storage insects. The damage potential of Tribolium castaneum in wheat grains stored in different storage bags at various storage periods was studied. A highly significant effect (P < 0.01) of the storage bags and storage periods was observed in variables measured (insect growth rate, damaged grains, grain weight loss and weight of insect feeding residues). The maximum mean insect growth rate (85.20 ± 2.80), percent damaged wheat grains (73.24 ± 0.17%), percent grain weight loss (21.14 ± 0.21%) and weight of insect feeding residues (2.15 ± 0.01 g) were recorded in wheat grains stored in cotton cloth bag at 150 d, whereas minimum mean insect growth rate (30.00 ± 0.00), percent damaged wheat grains (10.44 ± 0.16%), percent grain weight loss (0.82 ± 0.06%) and weight of insect feeding residues (0.22 ± 0.02 g) were recorded on wheat grains stored in hermetic bag due to 100% mortality of T. castaneum in hermetic bag at 30 d. A significant and positive correlation between storage periods, insect growth rate, damaged wheat grains, grain weight loss and weight of insect feeding residues was observed, except for the storage bags which were significantly and negatively correlated with other factors. In addition, the simple and linear regressions analysis were significant (P < 0.01), and all the equations for these analyses were fitted for the regression models and perfectly described the association between the dependent and independent variables. Hermetic bag proved resistance to external environment fluctuations in abiotic factors such as temperature and relative humidity. While grain moisture in all other bags fluctuated with external environment. The results showed that quantitative and qualitative losses of stored wheat grains depends not only the type of storage bags, but also on the storage periods. T. castaneum can have a negative impact on wheat grains stored in all storage bags except hermetic bag. So, it is recommended that hermetic bag be used at farmers’ level to achieve greater benefits by reducing T. castaneum infestation.

Lipid production in Dunaliella salina under autotrophic, heterotrophic, and mixotrophic conditions

The effects of autotrophic, heterotrophic, and mixotrophic conditions were examined on micro green alga Dunaliella salina (UTEX 200) in terms of cell growth, total chlorophyll concentration, and lipid production. Results revealed a minimum growth rate of microalgae in the heterotrophic condition which is not recommended for D. salina. When the cells were cultured in mixotrophic conditions containing different concentrations of acetate or glucose, in 100 mM acetate or 60 mM glucose, the highest levels of growth rate and lipid production were obtained compared with autotrophic culture; however, the chlorophyll concentration decreased. Moreover, a significant correlation between ROS production and lipid synthesis was observed. When the combined acetate and glucose was added to the culture, no increase in growth rate and lipid synthesis was observed. This might be due to substrate inhibition. In the presence of glucose, the acidification of culture and bleaching occurred. Results indicated that lipid production is not affected by acidified conditions. In general, our results confirmed that mixotrophic culture with 100 mM acetate or 60 mM glucose is the most appropriate culture for D. salina concerning high lipid production as well as high growth rate in the shortest period of time.

Monitoring fruit daily growth indicates the onset of mild drought stress in apple

This work tests the possibility to monitor fruit growth as a potential physiological indicator for tree water status and productive performance in apple, for potential implementation in decision support systems for irrigation scheduling. Starting from 10 weeks after full bloom (WAFB), a wide range of plant water statuses was induced in a “Gala” apple orchard by applying different shading (with red-50%, white-50%, and black-20% nets) and irrigation levels (severe-SS, moderate-MS and no-NS stress). For each net*irrigation treatment combination, midday stem water potential (mSWP) was assessed weekly, while fruit diameter variations were continuously monitored using automatic fruit gauges, from 10 WAFB until harvest. Leaf gas exchanges were also monitored at 14 and 16 WAFB. As expected, the different net*irrigation treatment combinations widely affected mSWP, leaf gas exchanges and fruit growth. On all dates of measurement, leaf gas exchanges were tightly correlated with mSWP, while daily fruit growth showed significant but weaker correlations with mSWP. In all cases, these relationships indicated the onset of drought stress below the threshold of about 1.2 g fruit−1 day−1, which corresponded to mSWP below -1 MPa. Almost no correlation was found between mSWP and the other parameters derived from the fruit daily growth pattern (midday, maximum and minimum absolute growth rates (AGR) and fruit shrinkage). Based on these results, we can conclude that, although fruit daily growth rate is not related to mSWP as tightly as leaf gas exchanges, it represents a promising physiological indicator to be implemented in a decision support system for irrigation scheduling. Specific fruit growth thresholds indicating the onset of drought should be defined, depending on the orchard conditions and productive target.

Soybean nitrogen fixation dynamics in Iowa, USA

The rainfed USA Midwestern region has deep, fertile soils and leads the USA in soybean [Glycine max, (L.) Merr.] production. Biological nitrogen (N) fixation (BNF) contributes a portion of the soybean N requirement, but variability in BNF is poorly understood and estimates of BNF for this region are rare. We established experiments in Iowa, USA to gain a better understanding of BNF and increase its predictability. We collected in-season BNF measurements accompanied by high temporal resolution soil and plant growth measurements. Across two years, two locations and two planting dates, we found that BNF contributed 23–65% of total aboveground N accumulation in soybean. The BNF rate was maximized at the early seed-filling period and varied from 1 to 3 kg N ha−1day−1. During seed filling period, the rate of BNF was related to crop growth rate (carbon (C) supply) but not to N accumulation by the reproductive organs (N demand). We found that a minimum crop growth rate of 135 kg dry matter ha−1day-1 is required to sustain maximum BNF rates. In contrast to BNF, the soil inorganic N uptake rate was related to seed N demand but not to C supply. Biomass production was the best predictor of total soybean BNF (R2 > 0.83). On average, 0.013 kg N was fixed per kg biomass produced. Across all trials, the N exported via seed was greater than the N imported via BNF, which suggests that Midwest US soybeans may reduce soil organic matter. We concluded that future research efforts should focus on increasing C – rather than N – availability during the seed filling period towards improving both grain yields and environmental sustainability.