THE PHOSPHORUS FRACTIONS OF BACILLUS CEREUS AND BACILLUS MEGATERIUM: II. A CORRELATION OF THE CHEMICAL WITH THE CYTOLOGICAL CHANGES OCCURRING DURING SPORE GERMINATION

1955 ◽  
Vol 1 (7) ◽  
pp. 525-548 ◽  
Author(s):  
P. C. Fitz-James
Keyword(s):  
Bacillus Cereus ◽  
Rna Synthesis ◽  
Dry Weight ◽  
Acid Synthesis ◽  
Nuclear Material ◽  
The Other ◽  
Other Hand ◽  
Soluble P ◽  
Labile P ◽  
Time Required

The oxygen uptake, the changes in the concentrations of the phosphorus (P) fractions, and the dry weights of Bacillus cereus and B. megaterium germinating in thick suspension were followed from the spore to the young vegetative cell. Parallel cytological studies were made using standard procedures of bacterial cytology. During the initial minutes of germination the dry weight of the spores fell, respiratory activity began, the concentration of cold trichloroacetic acid (TCA)-soluble P rose, and the concentration of a residual P fraction insoluble in hot TCA fell. In complete media, nucleic acid synthesis began soon after this initial activation and was accompanied by an uptake of P, a further rise in the acid-soluble P, and in the rate of respiration. The cells began to recover weight. Ribosenucleic acid (RNA) synthesis was detectable by about 10 min. after inoculation and desoxyribosenucleic acid (DNA) synthesis by 15–20 min. Following its initial rise, the rate of RNA synthesis declined and continued parallel to that of DNA for some 10 min. During this period, the uptake of P from the medium appeared to be depressed and the spores (B. cereus) changed in shape from ovoids to short rods. After this period, the RNA synthesis was steady throughout germination. The rise of DNA, on the other hand, was continuous and steady throughout, even in cultures where growth was synchronous. The nuclear material of germinating spores grew and separated in step with the continuous rise of DNA P and the increase in cell volume was of the same order as the increase in RNA P. Under crowded conditions, or in inadequate media, germinating spores and young vegetative cells of B. cereus showed a decreased RNA/DNA ratio and accumulations of labile P. Crowded cultures of B. megaterium, on the other hand, accumulated Sudan positive (fatty) granules, but no labile P. The time required for the germinating spore to duplicate its chromatin varied in different media and could, in some instances, be shortened by subculturing. Nevertheless, the product of this time of germination and the increase in RNA during the germination period approximated to a fixed value that was independent of medium, species, or cell concentration.

Function of coprophagous beetles (Coleoptera: Scarabaeidae, Geotrupidae, Hydrophilidae) in cattle pastures inferred from pitfall trapping data

2010 ◽  
Vol 27 (2) ◽  
pp. 85-91 ◽  
Author(s):  
Martin Šlachta ◽  
Jan Frelich ◽  
Tomáš Tonka
Keyword(s):  
Seasonal Variation ◽  
Spatial Variation ◽  
Dry Weight ◽  
Seasonal Distribution ◽  
The Other ◽  
Pitfall Trapping ◽  
Other Hand ◽  
Nested Anova ◽  
Species Groups ◽  
Dung Decomposition

Function of coprophagous beetles (Coleoptera: Scarabaeidae, Geotrupidae, Hydrophilidae) in cattle pastures inferred from pitfall trapping dataAn analysis of data on the dry weight biomass of coprophagous beetles in standardized dung (4.5 l) was conducted in order to characterize the spatial and the seasonal distribution of the beetles' biomass in cattle pastures and to elucidate their function in dung decomposition. Nested Anova with factors of farm, site (nested in farm), seasonal period and year was used to evaluate the effect of these factors on the biomass of four functional species groups: the dung dwellers ofScarabaeidae(subfamilyAphodiinae), the dung dwellers ofHydrophilidae, the small tunnellers ofScarabaeidae(subfamilyCoprinae) and the large tunnellers ofGeotrupidae. The spatial variation of biomass (between the sites and the farms) was insignificant (P>0.05) in the two dung-dweller groups and in the large-tunnellers group. On the other hand, a significant (P<0.05) seasonal variation of biomass was found in all but the large tunneller group. In dung dwellers, the spring biomass was formed mainly by two species,Aphodius prodromusandA. sphacelatus. In summer, most of the biomass was accounted for bySphaeridium lunatum, S. scarabaeoidesandA. rufipes. In the two tunneller groups,Onthophagus fracticornis, Geotrupes stercorariusandG. spinigerformed a majority of the biomass in dung.

scholarly journals Innovative Ultrasound-Assisted Approaches towards Reduction of Heavy Metals and Iodine in Macroalgal Biomass

Foods ◽  
2021 ◽  
Vol 10 (3) ◽  
pp. 649
Author(s):  
Estefanía Noriega-Fernández ◽  
Izumi Sone ◽  
Leire Astráin-Redín ◽  
Leena Prabhu ◽  
Morten Sivertsvik ◽  
...  
Keyword(s):  
Heavy Metals ◽  
Dry Weight ◽  
The Other ◽  
Laminaria Hyperborea ◽  
Other Hand ◽  
Macroalgal Biomass ◽  
Ultrasound Assisted ◽  
I 31

The aim of this work was to evaluate the potential of ultrasound (US), alone or in combination with mild heating and/or EDTA towards reduction of As, Cd, I, and Hg content of Laminaria hyperborea. Concentrations of As, Cd, I, and Hg of 56.29, 0.596, 7340, and <0.01 mg kg−1 of dry weight, respectively, were found in L. hyperborea blades. Treatment with US at 50 °C increased approx. 2-fold the amount of As released, although did not affect significantly the content of Cd or I, as compared to control (no US) samples. Reducing the temperature to 8 °C significantly decreased the effect of US, but heating at 80 °C did not cause a significant effect as compared to treatments at 50 °C. On the other hand, treatment with 0.1 N EDTA at 50 °C enhanced the percentage of Cd released by approximately 7-fold, regardless of sonication. In the present work, the combination of US and EDTA at 50 °C for 5 min led to a significant reduction of the As (32%), Cd (52%) and I (31%) content in L. hyperborea, thus improving the product’s safety for consumers.

scholarly journals Optimization of a Kitting Line: A Case Study

Robotics ◽  
2019 ◽  
Vol 8 (3) ◽  
pp. 70 ◽  
Author(s):  
Nicola Comand ◽  
Riccardo Minto ◽  
Giovanni Boschetti ◽  
Maurizio Faccio ◽  
Giulio Rosati
Keyword(s):  
Feeding Rate ◽  
The Other ◽  
Assembly System ◽  
Inspection System ◽  
Flexible Assembly ◽  
Vision Inspection ◽  
Other Hand ◽  
Time Required ◽  
The Cost

Assembly kitting lines typically deal with components that present different quantities in the final kit. Re-configurable feeders are not advisable for low quantity components since this solution leads to high inefficiency, due to the time required for retooling and for the feeding rate unbalance between the components. On the other hand a fully flexible feeder can increase the flexibility of the system at the cost of reducing the throughput. An assembly kitting problem was therefore addressed in different ways for low quantity components and high quantity components, studying the two different subsystems that compose a hybrid flexible assembly system. To optimize the re-configurable feeders, which supply the high quantity components, the opening sequence of a system composed by several hoppers was analyzed. We propose a solution which replaces the weighing device with a vision inspection system, showing its impact on the productivity of the line. A model coded into a Matlab script was developed to perform the optimization of the system and understand its behavior. Furthermore a fully flexible assembly system was developed in the laboratory in order to test the kitting of the low quantity components with the proposed subsystem. Finally the Overall Equipment Effectiveness of the line was calculated to evaluate the possible improvements obtained by the proposed solution.

Regenerative studies on the detached leaves of Echeveria elegans. Regeneration and growth in leaves

1973 ◽  
Vol 51 (2) ◽  
pp. 451-456 ◽  
Author(s):  
M. V. S. Raju ◽  
James E. Hines
Keyword(s):  
Metabolic Activity ◽  
Dry Weight ◽  
The Other ◽  
Inhibitory Influence ◽  
Other Hand ◽  
Detached Leaves

Detached leaves of Echeveria elegans Bgr. produce both roots and shoots. However, when their bases are severed, they tend to produce only roots. It was observed that roots had to be present on detached leaves, bases removed or not, in order to have an increase in size and also in dry weight. The growth in size was found to be due mainly to enlargement of cells, and the increase in dry weight was presumably due to maintenance of normal metabolic activity in the detached leaves. Thus detached leaves of E. elegans have a greater potential for growth than is normally realized by the leaves that are mature and still attached to the parent axis. The vigorously growing shoots seem to have an inhibitory influence on growth in the detached leaves. Roots on detached leaves, on the other hand, seem to play an important role not only in the delaying of senescence but also in reducing the inhibitory influence of shoots. Roots alone appeared to bring about "uncontrolled" enlargement of cells and consequently lesions were formed on the leaves, which finally died off. Thus growth, regeneration, and senescence in the detached leaves appear to be correlative phenomena.

Incidence de l'aération sur le traitement par compostage des sous-produits du palmier dattier contaminés parFusarium oxysporumf.sp.albedinis

2005 ◽  
Vol 51 (1) ◽  
pp. 69-77 ◽  
Author(s):  
K Chakroune ◽  
M Bouakka ◽  
A Hakkou
Keyword(s):  
Total Nitrogen ◽  
Date Palm ◽  
Dry Weight ◽  
Initial Mixture ◽  
Phoenix Dactylifera ◽  
The Other ◽  
Mineral Matter ◽  
Other Hand ◽  
Phoenix Dactylifera L ◽  
Cooling Phase

Composting of date palm (Phoenix dactylifera L.) residues contaminated with Fusarium f.sp oxysporum albedinis, causal agent of the vascular wilt (Bayoud) of the date palm, has been achieved. The effect of the aeration of the piles by manual turning has been studied. The maintenance of an adequate humidity of 60%–70%, necessary to the good progress of the composting process, required the contribution of 11.4 L of water/kg of the dried residues. The evolution of the temperatures in the three piles presents the same phases. A latency phase, followed after 2–3 d of composting by a thermophilic phase, which lasts about 24 d, where the temperature remains elevated between 50 and 70 °C. Then a cooling phase that takes about 15 d, during which the temperatures fall to values between 25 and 35 °C, near room temperature. Fusarium f.sp oxysporum albedinis is eliminated completely during the thermophilic phase of composting, and increasing frequencies of turning accelerate its disappearance to a certain extent. On the other hand, pH remained steady and relatively basic oscillating between 8.2 and 8.7. Ninety percent (90%) of the the date palm residues are composed exclusively of organic matters. The total nitrogen represents only 0.4%. The contribution of manure decreases the ratio of carbon to nitrogen (C/N) from 115 to 48 in the initial mixture. After 80 d of composting and according to the frequency of return up, there is a reduction of the granulometry of the substratum, the C/N ratio (from 29% to 44%), the organic matter (from 15% to 23%), the total volume (from 25% to 35%), and of the dry weight of the swaths (from 16% to 24%). On the other hand there is an increase in total nitrogen rate (from 20% to 40%) and in the mineral matter (from 23% to 35%).Key words: composting, palm date, Fusarium oxysporum f.sp. albedinis.

scholarly journals On the saturation pressures of steam (170° to 374° C.)

1933 ◽  
Vol 231 (694-706) ◽  
pp. 147-205 ◽  
Keyword(s):  
Equilibrium State ◽  
The Other ◽  
Other Hand ◽  
Time Required ◽  
Limits Of Error

The efforts which are being made through the agency of the International Steam Tables Conferences to co-ordinate investigations on steam, and to set down its measured properties in a series of tables and figures which shall be within agreed limits of error, and consistent with each other thermodynamically, cannot very well succeed, unless it be proved that steam is consistent in its behaviour. If there are differences, for instance, traceable to the time required for the constituent molecules of steam to reach an equilibrium state, then it might be difficult to achieve concordance between measurements of the properties of steam carried out by different methods. If, on the other hand, no such differences are exhibited, then it would seem that it is only a matter of care and of time to achieve a set of tables which shall represent the true behaviour of steam and which can be brought within a thermodynamically consistent scheme.

Immobilization of Uranium at Nanoscale by Bacillus cereus 12-2 at Different U(VI) Concentration

2019 ◽  
Vol 19 (11) ◽  
pp. 7131-7138
Author(s):  
Jian Zhang ◽  
Hongxin Chen ◽  
Jianning Song ◽  
Hong Deng ◽  
Zhi Chen ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Bacillus Cereus ◽  
Functional Groups ◽  
Adsorption Equilibrium ◽  
Uranium Concentration ◽  
Removal Rate ◽  
Dry Weight ◽  
Transmission Electron ◽  
Low Concentrations ◽  
Time Required

Uranium can be immobilized as nanoscale minerals by biomineralization under aerobic conditions. Current researches on nonreductive biomineralization of U(VI) mainly focus on revealing the mechanisms associated with functional groups and enzymes. However, studies on the effect of initial uranium concentration on the uranium bio-immobilization are relatively rare. This paper researched the immobilization of U(VI) at different concentrations by Bacillus cereus 12-2. Adsorption experiments showed that the adsorption equilibrium was rapidly reached within 10 min when U(VI) concentration was 25 mg/L while over 2 h when U(VI) concentration was 200 mg/L. The biological adsorption capacity improved gradually from 24.68 to 163.17 mg/g (dry weight) as U(VI) concentration increased, but the removal rate of uranium decreased from about 100% to 80%. X-ray diffraction (XRD) showed that nanoscale uramphite ((NH4)(UO2)PO4·3H2O) formation time was 4, 4, 12 and 24 h, respectively when initial U(VI) concentration was 25, 50, 75 and 100 mg/L. No mineral was formed after reaction for 24 h when U(VI) concentration was 200 mg/L. Uramphite had better peaks in spectrum after 50 mg/L U(VI) had interacted with Bacillus cereus 12-2 for 4 h. XRD, SEM (scanning electron microscopy) and TEM (transmission electron microscopy) indicated that a large number of amorphous uranium-containing particles appeared extracellularly after 10 min and nanoscale uramphite formed intracellularly after 4 h when uranium concentration was 50 mg/L. This study showed that the time required for adsorption equilibrium and mineralization by Bacillus cereus 12-2 was shorter when the initial U(VI) concentration was lower within a certain range. This phenomenon could be attributed to the increase of relative content of functional groups and the decrease of cytotoxicity of uranium at low concentrations. This work had certain guiding significance for further understanding the mechanism of uranium biomineralization and the application of Bacillus cereus 12-2 under actual uranium-contaminated environments.

scholarly journals SPATIAL DISTRIBUTION OF TRACE METALS (Pb, Cr, Cu AND Zn) IN SEDIMENTS OF THE BERAU DELTA, EAST KALIMANTAN AND THEIR ACCUMULATION IN BENTHIC BIOTA

2018 ◽  
Vol 32 (2) ◽  
pp. 89-94 ◽  
Author(s):  
Z. Arifin ◽  
T. A. Koesmawati
Keyword(s):  
Spatial Distribution ◽  
Trace Metals ◽  
Dry Weight ◽  
Coastal Ecosystem ◽  
The Other ◽  
Metal Concentrations ◽  
East Kalimantan ◽  
Other Hand ◽  
Cu And Zn

Berau delta is a coastal ecosystem where man-made activities are relatively low. The present study has investigated spatial distribution of Pb, Cr, Cu and Zn in sediments and their implication to benthic biota. The result of our study showed that metal concentrations varied from undetected to 55.53 mg kg-1 for Pb and from 3.28 to 22.9 mg kg-1 for Cu, while for Cr and Zn vary from 9.65 to 64.67 mg kg-1 and 10.00 to 1,200 mg kg-1, respectively. The concentrations of Pb, Cu, Cr and Zn in Anadara sp were 7.53 ± 2.06, 4.92 ± 0.55, 1.44 ± 0.12 and 97.87 ± 9.12 mg kg-1 dry weight (dw), respectively. On the other hand, the Pb, Cr, Cu and Zn in Telescopium mauritsi were 4.49 ± 0.03, 0.87 ± 0.05, 259.0 ± 0.01 and 64.78 ± 0.01 mg kg-1 dw, respectively. In conclusion, spatial distribution of trace metals (Pb, Cu, Cr and Zn) in sediments showed that higher concentrations were found in the southern part of the delta, and the accumulation of the metals by mollusk might reflect natural concentrations in biota.

Aeroplane Tail Loads for Longitudinal Manoeuvres

1952 ◽  
Vol 56 (502) ◽  
pp. 789-800
Author(s):  
G. W. Smith ◽  
J. B. Rea
Keyword(s):  
Fourier Series ◽  
Transfer Function ◽  
Standard Method ◽  
Angle Of Attack ◽  
The Other ◽  
Time Saving ◽  
Other Hand ◽  
Additional Input ◽  
Time Required

SummaryThis paper deals with the application of the Transfer Function-Fourier (T.F.F.) Method to the calculation of longitudinal manoeuvring tail loads for aeroplanes.It has been found that the tail loads computed by this method agree very well with those computed by the standard method outlined in Ref. 1. The main advantages of the T.F.F. method are the time saving and the convenience in handling an arbitrary elevator input. Having once calculated the transfer function between elevator input and tail angle of attack output, it may be used repeatedly to compute the longitudinal manoeuvring tail loads for various arbitrary elevator inputs. This is done by simply expressing the input as a Fourier series and multiplying each term in the series by the value of the transfer function for the corresponding frequency. Then the resulting output series is summed at enough points to obtain a plot of the transient output. This process can be done in approximately one hour of engineering time for each arbitrary elevator input, exclusive of machine calculating time. The machine (usually I.B.M.) calculating time is about half an hour per input. On the other hand, experience has shown that the engineering time required per input by the standard method is approximately forty hours for the first input, and approximately five hours for each additional input.It is concluded that the calculation of longitudinal manoeuvring tail loads by the T.F.F. method is accurate, dependable, especially adaptable to machine methods, and can conveniently handle arbitrary inputs.

Über die Beziehungen der RNS- und Proteinsynthese zum Zellkern in Siebzellen von Vicia faba

1964 ◽  
Vol 19 (11) ◽  
pp. 1066-1071 ◽  
Author(s):  
Stefanie Neumann ◽  
Reinhold Wollgiehn
Keyword(s):  
Vicia Faba ◽  
Rna Synthesis ◽  
The Other ◽  
Other Hand ◽  
Cytoplasmic Rna ◽  
Nuclear Rna ◽  
Sieve Tubes

Autoradiographic investigations on the dependency of the RNA and protein syntheses on the nucleus have been carried out in sieve tubes of Vicia faba.In young nucleated sieve tubes 3H-uridine is incorporated primarily into the nuclear RNA and later into the cytoplasmic RNA. In sieve tubes with degenerated nuclei no incorporation of uridine in RNA takes place. On the other hand, 3H-phenylalanine is incorporated also into the proteins of old sieve tubes without RNA synthesis.

Sign in / Sign up

Export Citation Format

Share Document