Growth dynamics of cyclomaltodextrin glucanotransferase producing Bacillus circulans var. alkalophilus

1990 ◽  
Vol 36 (3) ◽  
pp. 176-182 ◽  
Author(s):  
Mauri J. Mäkelä ◽  
Sari K. Paavilainen ◽  
Timo K. Korpela
Keyword(s):  
Time Course ◽  
Growth Parameters ◽  
Growth Dynamics ◽  
Point Of View ◽  
Bacillus Circulans ◽  
Amylolytic Enzyme ◽  
Bulk Growth ◽  
Atcc Strain ◽  
Total Carbohydrates ◽  
Cyclomaltodextrin Glucanotransferase

The time course of the growth of cyclomaltodextrin glucanotransferase (EC 2.4.1.19; CGTase) producing Bacillus circulans var. alkalophilus (ATCC 21783) was studied using shaking-flask cultivations. The growth curve was diauxic and during the initial phase the pH decreased sharply by 1.3–1.5 units. Most of the total carbohydrates disappeared prior to the bulk growth, which corresponded to a transient peak of amylolytic enzyme activity and of reducing sugars followed by acid production. During active cell growth the pH recovered by about 0.5 units and 65% of the final CGTase appeared in the medium. Another 20% was produced during the stationary phase and 15% was produced in the death phase. The growth dynamics of two randomly selected alkalophilic Bacillus strains (ATCC 27647 and 27557) were compared with those of ATCC-strain 21783. The reference strains showed related growth behavior with the exception that the timing and magnitudes of the changes in the growth parameters measured were different. The effects of carbon source (starch), nitrogen source (yeast extract plus Bacto-pantone), sodium carbonate, and temperature were studied from the point of view of CGTase production. Key words: cyclomaltodextrin glucanotransferase; alkalophilic bacilli; cyclodextrins.

Histology and histochemistry of elongating needles of Pinus strobus subjected to a long-duration, low-concentration exposure of sulfur dioxide

1981 ◽  
Vol 59 (12) ◽  
pp. 2558-2567 ◽  
Author(s):  
K. E. Percy ◽  
R. T. Riding
Keyword(s):  
Growth Parameters ◽  
Succinic Dehydrogenase ◽  
Pinus Strobus ◽  
Wall Region ◽  
Growth Reduction ◽  
Succinic Dehydrogenase Activity ◽  
Long Duration ◽  
Bud Set ◽  
Total Carbohydrates ◽  
External Growth

Two-year-old seedlings of Pinus strobus were grown from budbreak to bud set (11 weeks) in air containing 132 ± 26 μg SO2∙m−3. Histological and histochemical effects on elongating needles were examined. Cellular injury was restricted to mesophyll parenchyma. Affected cells manifested a progressive alteration of protoplast staining proportional to the degree of injury. Total carbohydrates and plastids aggregated at cell walls. Total proteins and proteins containing sulfhydryl–disulfide groups decreased. Phospholipid staining in the plasmalemma – cell wall region appeared reduced. Succinic dehydrogenase activity was enhanced and was apparent longer in injured cells. Needle ontogeny was slowed in fumigated seedlings. There were no significant differences in external growth parameters after 11 weeks. The injury can, therefore, be classified as latent or hidden. The SO2 effects could contribute to a growth reduction in successive increments.

scholarly journals Data-driven multiscale modeling reveals the role of metabolic coupling for the spatio-temporal growth dynamics of yeast colonies

2018 ◽  
Author(s):  
Jukka Intosalmi ◽  
Adrian C. Scott ◽  
Michelle Hays ◽  
Nicholas Flann ◽  
Olli Yli-Harja ◽  
...  
Keyword(s):  
Experimental Data ◽  
Time Course ◽  
Model Development ◽  
Growth Dynamics ◽  
Colony Growth ◽  
Data Driven ◽  
Coarse Grained ◽  
Intercellular Signaling ◽  
Growth Data ◽  
Metabolic Coupling

AbstractMotivationMulticellular entities, such as mammalian tissues or microbial biofilms, typically exhibit complex spatial arrangements that are adapted to their specific functions or environments. These structures result from intercellular signaling as well as from the interaction with the environment that allow cells of the same genotype to differentiate into well-organized communities of diversified cells. Despite its importance, our understanding on how cell–cell and metabolic coupling produce functionally optimized structures is still limited.ResultsHere, we present a data-driven spatial framework to computationally investigate the development of one multicellular structure, yeast colonies. Using experimental growth data from homogeneous liquid media conditions, we develop and parameterize a dynamic cell state and growth model. We then use the resulting model in a coarse-grained spatial model, which we calibrate using experimental time-course data of colony growth. Throughout the model development process, we use state-of-the-art statistical techniques to handle the uncertainty of model structure and parameterization. Further, we validate the model predictions against independent experimental data and illustrate how metabolic coupling plays a central role in colony formation.AvailabilityExperimental data and a computational implementation to reproduce the results are available athttp://research.cs.aalto.fi/csb/software/multiscale/[email protected],[email protected]

scholarly journals Data-driven multiscale modeling reveals the role of metabolic coupling for the spatio-temporal growth dynamics of yeast colonies

2019 ◽  
Vol 20 (1) ◽  
Author(s):  
Jukka Intosalmi ◽  
Adrian C. Scott ◽  
Michelle Hays ◽  
Nicholas Flann ◽  
Olli Yli-Harja ◽  
...  
Keyword(s):  
Experimental Data ◽  
Time Course ◽  
Growth Dynamics ◽  
Colony Growth ◽  
Data Driven ◽  
Coarse Grained ◽  
Colony Development ◽  
Intercellular Signaling ◽  
Metabolic Coupling ◽  
The Impact

Abstract Background Multicellular entities like mammalian tissues or microbial biofilms typically exhibit complex spatial arrangements that are adapted to their specific functions or environments. These structures result from intercellular signaling as well as from the interaction with the environment that allow cells of the same genotype to differentiate into well-organized communities of diversified cells. Despite its importance, our understanding how this cell–cell and metabolic coupling lead to functionally optimized structures is still limited. Results Here, we present a data-driven spatial framework to computationally investigate the development of yeast colonies as such a multicellular structure in dependence on metabolic capacity. For this purpose, we first developed and parameterized a dynamic cell state and growth model for yeast based on on experimental data from homogeneous liquid media conditions. The inferred model is subsequently used in a spatially coarse-grained model for colony development to investigate the effect of metabolic coupling by calibrating spatial parameters from experimental time-course data of colony growth using state-of-the-art statistical techniques for model uncertainty and parameter estimations. The model is finally validated by independent experimental data of an alternative yeast strain with distinct metabolic characteristics and illustrates the impact of metabolic coupling for structure formation. Conclusions We introduce a novel model for yeast colony formation, present a statistical methodology for model calibration in a data-driven manner, and demonstrate how the established model can be used to generate predictions across scales by validation against independent measurements of genetically distinct yeast strains.

scholarly journals Role of mechanical cues and hypoxia on the growth of tumor cells in strong and weak confinement: A dual in vitro–in silico approach

2020 ◽  
Vol 6 (13) ◽  
pp. eaaz7130 ◽  
Author(s):  
V. Le Maout ◽  
K. Alessandri ◽  
B. Gurchenkov ◽  
H. Bertin ◽  
P. Nassoy ◽  
...  
Keyword(s):  
In Silico ◽  
Time Course ◽  
Growth Dynamics ◽  
Tumor Model ◽  
Mechanistic Modeling ◽  
Physical Factors ◽  
Factors Affecting ◽  
Numerical Studies

Characterization of tumor growth dynamics is of major importance for cancer understanding. By contrast with phenomenological approaches, mechanistic modeling can facilitate disclosing underlying tumor mechanisms and lead to identification of physical factors affecting proliferation and invasive behavior. Current mathematical models are often formulated at the tissue or organ scale with the scope of a direct clinical usefulness. Consequently, these approaches remain empirical and do not allow gaining insight into the tumor properties at the scale of small cell aggregates. Here, experimental and numerical studies of the dynamics of tumor aggregates are performed to propose a physics-based mathematical model as a general framework to investigate tumor microenvironment. The quantitative data extracted from the cellular capsule technology microfluidic experiments allow a thorough quantitative comparison with in silico experiments. This dual approach demonstrates the relative impact of oxygen and external mechanical forces during the time course of tumor model progression.

scholarly journals Pollutant removal and growth dynamics of macrophyte species for faecal sludge treatment with constructed wetland technology

2019 ◽  
Vol 80 (6) ◽  
pp. 1145-1154
Author(s):  
Agyemang Richard Osei ◽  
Yacouba Konate ◽  
Felix Kofi Abagale
Keyword(s):  
Constructed Wetland ◽  
Growth Parameters ◽  
Oxygen Demand ◽  
Growth Dynamics ◽  
Pilot Scale ◽  
Pollutant Removal ◽  
Local Context ◽  
Organic Chemical ◽  
Bambusa Vulgaris ◽  
Faecal Sludge

Abstract Constructed wetland technology is an innovative engineering technique for faecal sludge (FS) management. The presence of emergent macrophytes enhances the important processes of evapotranspiration, sludge mineralisation, and contaminant reduction. Consequently, selecting a species that can withstand the difficult sludge contaminated conditions within a local context is vital. This study monitored the pollutant removal potentials and growth dynamics of Bambusa vulgaris and Cymbopogon nardus as promising macrophytes for the constructed wetland technology in the Sudano-Sahelian context. The experiment, at pilot scale, consisted of plastic reactors (27 litre) filled with filter media of sand and fine gravels at the base, and planted with the selected species. Pollutant removal efficiencies were evaluated based on differences between influent and effluent concentrations, and physiological growth parameters of plant height, number of leaves and number of plants were monitored monthly. Total annual sludge loading rate of 31.4 and 103.4 kg TS/(m2·yr) (TS: total solids) were determined for FS + wastewater (acclimatisation phase) and FS load respectively. Both species recorded appreciable pollutant removal efficiency >80% for the organic (chemical oxygen demand), nutrients (PO43_P and NH4-N) and solid (total suspended solids and total volatile solids) contents. The species thus demonstrated satisfactory performance of resistance for faecal polluted wetland conditions.

Analysis of the effect of n fertilisation on the growth dynamics of winter wheat varieties using the hunt-parsons model

2011 ◽  
Vol 59 (1) ◽  
pp. 35-45
Author(s):  
E. Sugár ◽  
Z. Berzsenyi
Keyword(s):  
Winter Wheat ◽  
Leaf Area ◽  
Dry Matter ◽  
Growth Parameters ◽  
Growth Dynamics ◽  
Dry Matter Accumulation ◽  
Wheat Varieties ◽  
Mean Values ◽  
N Treatment ◽  
Winter Wheat Varieties

The effect of nitrogen (N) fertilisation on the growth of winter wheat varieties was examined in three diverse years using the functional method of growth analysis. The main plot in the two-factorial, split-plot experiment was the N treatment and the subplot the variety. The wheat varieties Mv Toborzó (extra-early), Mv Palotás (early) and Mv Verbunkos (mid-early) were treated with N rates of 0, 80, 160 and 240 kg N ha−1 (N0, N80, N160, N240). The Hunt-Parsons (HP) program fitted a third-degree exponential function to the dry matter and leaf area data. In 2007 and 2008 dry matter accumulation continued up to the N240 rate and in 2009 to the N160 rate. In all three years the highest value was recorded for Mv Verbunkos (4.62 g plant−1 in 2007, 4.63 g in 2008 and 4.51 g in 2009). The highest value of maximum leaf area (237.5 cm2) was found for Mv Verbunkos in the N240 treatment. The maximum values of leaf area in each N treatment, averaged over years and varieties (cm2 plant−1), were as follows: N0: 86.2; N80: 141.0; N160: 164.0; N240: 173.1. The parameter AGRmean exhibited the highest value (8.04 g day−1 102) in the N160 treatment, while among the varieties Mv Verbunkos had the highest mean value (7.18 g day−1 102). The highest value of RGRmean was achieved by Mv Toborzó in the N160 treatment in 2009 (3.94 g g−1 day−1 102). The value of NARmean increased up to fertiliser rates of N160 and N240, with mean values (g m−1 day−1) of N0: 2.35, N80: 2.44, N160: 2.53 and N240: 2.47. The highest value of NAR (3.29 g m−1 day−1) was obtained for Mv Palotás in the N160 treatment in 2008. On average the greatest value of LARmax was recorded in the N160 treatment (172.8 cm2 g−1), while the highest absolute value (213.6 cm2 g−1) was achieved by Mv Toborzó in 2008. The unfavourable effect of the drought in 2007 was clearly reflected in the values of the growth parameters.

scholarly journals Predictability and Error Growth Dynamics in Cloud-Resolving Models

2007 ◽  
Vol 64 (12) ◽  
pp. 4467-4478 ◽  
Author(s):  
Cathy Hohenegger ◽  
Christoph Schär
Keyword(s):  
High Resolution ◽  
Initial Perturbation ◽  
Growth Dynamics ◽  
Point Of View ◽  
Atmospheric Environment ◽  
Ensemble Prediction ◽  
Computational Domain ◽  
Error Growth ◽  
Ensemble Techniques

Abstract While the benefits of ensemble techniques over deterministic numerical weather predictions (NWP) are now widely recognized, the prospects of ensemble prediction systems (EPS) at high computational resolution are still largely unclear. Difficulties arise due to the poor knowledge of the mechanisms promoting rapid perturbation growth and propagation, as well as the role of nonlinearities. In this study, the dynamics associated with the growth and propagation of initial uncertainties is investigated by means of real-case high-resolution (cloud resolving) NWP integrations. The considered case is taken from the Mesoscale Alpine Programme intensive observing period 3 (MAP IOP3) and involves convection of intermediate intensity. To assess the underlying mechanisms and the degree of linearity upon the predictability of the flow, vastly different initial perturbation methodologies are compared, while all simulations use identical lateral boundary conditions to mimic a perfectly predictable synoptic-scale flow. Comparison of the perturbation methodologies indicates that the ensuing patterns of ensemble spread converge within 11 h, irrespective of the initial perturbations employed. All methodologies pinpoint the same meso-beta-scale regions of the flow as suffering from predictability limitations. This result reveals the important role of nonlinearities. Analysis also shows that hot spots of error growth can quickly (1–2 h after initialization) develop far away from the initial perturbations. This rapid radiation of the initial uncertainties throughout the computational domain is due to both sound and gravity waves, followed by the triggering and/or growth of perturbations over regions of convective instability. The growth of the uncertainties is then limited by saturation effects, which in turn are controlled by the larger-scale atmospheric environment. From a practical point of view, it is suggested that the combined effects of rapid propagation, sizeable amplification, and inherent nonlinearities may pose severe difficulties for the design of EPS or data assimilation techniques related to high-resolution quantitative precipitation forecasting.

scholarly journals Representation of Body Orientation in Vestibular-Defective Patients Before and After Unilateral Vestibular Loss

2021 ◽  
Vol 15 ◽  
Author(s):  
Liliane Borel ◽  
Jacques Honoré ◽  
Mathilde Bachelard-Serra ◽  
Jean-Pierre Lavieille ◽  
Arnaud Saj
Keyword(s):  
Time Course ◽  
Recovery Period ◽  
Body Representation ◽  
Acute Stage ◽  
Point Of View ◽  
Spatial Neglect ◽  
Body Orientation ◽  
Vestibular Disorder ◽  
Vestibular Loss ◽  
Before And After

Introduction: The unilateral vestibular syndrome results in postural, oculomotor, perceptive, and cognitive symptoms. This study was designed to investigate the role of vestibular signals in body orientation representation, which remains poorly considered in vestibular patients.Methods: The subjective straight ahead (SSA) was investigated using a method disentangling translation and rotation components of error. Participants were required to align a rod with their body midline in the horizontal plane. Patients with right vestibular neurotomy (RVN; n =8) or left vestibular neurotomy (LVN; n = 13) or vestibular schwannoma resection were compared with 12 healthy controls. Patients were tested the day before surgery and during the recovery period, 7 days and 2 months after the surgery.Results: Before and after unilateral vestibular neurotomy, i.e., in the chronic phases, patients showed a rightward translation bias of their SSA, without rotation bias, whatever the side of the vestibular loss. However, the data show that the lower the translation error before neurotomy, the greater its increase 2 months after a total unilateral vestibular loss, therefore leading to a rightward translation of similar amplitude in the two groups of patients. In the early phase after surgery, SSA moved toward the operated side both in translation and in rotation, as typically found for biases occurring after unilateral vestibular loss, such as the subjective visual vertical (SVV) bias.Discussion and Conclusion: This study gives the first description of the immediate consequences and of the recovery time course of body orientation representation after a complete unilateral vestibular loss. The overall evolution differed according to the side of the lesion with more extensive changes over time before and after left vestibular loss. It is noteworthy that representational disturbances of self-orientation were highly unusual in the chronic stage after vestibular loss and similar to those reported after hemispheric lesions causing spatial neglect, while classical ipsilesional biases were reported in the acute stage. This study strongly supports the notion that the vestibular system plays a major role in body representation processes and more broadly in spatial cognition. From a clinical point of view, SSA appeared to be a reliable indicator for the presence of a vestibular disorder.

scholarly journals Temporal Responses to Direct and Induced Iron Deficiency in Parietaria judaica

Agronomy ◽  
2020 ◽  
Vol 10 (7) ◽  
pp. 1037
Author(s):  
Liliana Tato ◽  
Monirul Islam ◽  
Tanja Mimmo ◽  
Graziano Zocchi ◽  
Gianpiero Vigani
Keyword(s):  
Time Course ◽  
Temporal Dynamics ◽  
Growth Parameters ◽  
Root Exudation ◽  
Calcareous Soils ◽  
Late Response ◽  
Crop Species ◽  
High Calcium ◽  
Alkaline Conditions ◽  
High Concentrations

Parietaria judaica grows in highly calcareous environments, overcoming the low bioavailability of Fe caused by elevated pH. The aim of this work was to investigate the temporal dynamics of root exudation of P. judaica under Fe deficiency conditions. As high concentrations of bicarbonate and Ca2+ in calcareous soils interfere with the general plant mineral nutrition, two different alkaline growing conditions were applied to distinguish the effects due to the high pH from the responses induced by the presence of high calcium carbonate concentrations. Growth parameters and physiological responses were analyzed during a 7 day time course—shoot and root biomass, chlorophyll and flavonoid contents in leaves, root accumulation, and exudation of organic acids and phenolics were determined. Different responses were found in plants grown in the presence of bicarbonate and in the presence of an organic pH buffer, revealing a time- and condition-dependent response of P. judaica and suggesting a stronger stress in the buffer treatment. The high tolerance to alkaline conditions may be related to an earlier and greater exudation rate of phenolics, as well as to the synergistic effect of phenolics and carboxylic acids in root exudates in the late response. The identification of the main functional traits involved in tolerance to low Fe availability in a wild species could offer crucial inputs for breeding programs for application to crop species.

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