Seascape ecological view as a new insight of benthic foraminiferal community

2021 ◽  
Author(s):  
Hiroshi Kitazato
Keyword(s):  
Open Space ◽  
Test Group ◽  
Coralline Algae ◽  
High Concentration ◽  
Calcium Carbonates ◽  
Minor Elements ◽  
Magnesian Calcite ◽  
Ecological View ◽  
Microhabitat Segregation ◽  
Foraminiferal Test

<p>Foraminifers secrete various chemicals for chamber walls. They are calcium carbonates such as calcite, aragonite, Mg-calcite, organic compounds for agglutinated chambers and/or organic cemented test walls.  Foraminiferal test walls basically form according to genetic information.  However, same test group is tended to gather at specific microenvironments.  For instance, turf shaped algal microhabitat such as coralline algae at rocky shore is composed of both frond and thallus parts as microhabitat.  Frond part is open space where fresh seawater moves inbetween one frond and the other.  <em>Elphidium crispum</em>, <em>Pararotalia nipponica</em> and <em>Patellina corrugate</em> and other calcareous foraminifers dwell at frond surface.  In contrast, thallus part is muddy and high concentration of organic matters.  The thallus part shows less oxygenated than frondal part as the space is close.  Microbial cascades are developed at thallus part.  Minor elements such as Mg or Sr are relatively high in sediment.  Soft-shelled forms such as <em>Allogromia</em>, gromiid, agglutinated forms and miliolids groups with high magnesian calcite tests flourish at the thallus part.</p><p>Microhabitat segregation and microenvironmental differences may cause similar biomineralization of benthic foraminiferal tests.  I would like to stress that micro-seascape should be important to characterize benthic foraminiferal assemblages.</p>

Biogeohemical significance of Intracellular calcification by Cyanobacteria

2020 ◽  
Author(s):  
Neha Mehta ◽  
Feriel-Skouri Panet ◽  
Karim Benzerara
Keyword(s):  
Carbon Capture ◽  
Alkaline Earth ◽  
Physiological Role ◽  
Vital Role ◽  
Amorphous Calcium Carbonate ◽  
High Concentration ◽  
In Vitro Synthesis ◽  
Calcium Carbonates ◽  
Alkaline Earth Elements

<p>Cyanobacteria are an abundant and diverse group of photosynthetic bacteria that have shaped Earth’s environment for billions of years and play a vital role in the cycling of numerous elements such as carbon, calcium, and phosphorus. In particular, their impact on the global carbon cycle is of significant interest in the context of carbon capture and climate change, as they sequester atmospheric CO<sub>2</sub> into organic carbon and biogenic calcium carbonates (CaCO<sub>3</sub>) through a process called calcification.  The process of calcification has long been considered as extracellular and non-biologically controlled. However, recently, several cyanobacterial species have been reported to form intracellular amorphous calcium carbonate (ACC) inclusions. These cyanobacteria were found in diverse environments and accumulate high concentrations of AEE (Ca, Ba and Sr) from solutions undersaturated with respect to AEE-carbonate phases. Moreover, one of these cyanobacteria species, <em>G. lithophora</em> was shown to selectively accumulate stable and radioactive alkaline earth elements (AEE) within the intracellular amorphous carbonates and/or polyp inclusions (Mehta et al., 2019). Recently, it was confirmed that cyanobacteria forming intracellular ACC contained a much higher content of alkaline earth elements (AEE) than all other cyanobacteria (DeWever et al., 2019). The high concentration of Ba and Sr within these intracellular inclusions was surprising because Ba and Sr have usually been considered as having no physiological role at all. The high concentration of Ca within these intracellular inclusions was directly in contrast with the traditional paradigm of cells maintaining a state of homeostasis with respect to Ca. Furthermore, Sr/Ca and Ba/Ca ratios in these ACC inclusions were very different from those expected from abiotic precipitation in the solution surrounding the cells (Cam et al. 2015). To understand the biological driver behind these observations, first, I will present a review of the above mentioned “vital effects” in the context of intracellular calcification in cyanobacteria. Second, using batch incubation experiments, I will show that high Ca concentrations are vital not only for the growth of <em>G. lithophora</em>, but also for the uptake of Ba by <em>G. lithophora</em>. Lastly, I will examine Ca homeostasis in ACC forming cyanobacterial strains by using an antagonist/inhibitor of a known channel/transporter involved in Ca transport.  Overall, these insights will shed some light on the role of cyanobacteria forming intracellular ACC on carbonate (bio)mineralization, in both modern and ancient Earth’s environment. </p><p>Reference:</p><p>N Mehta, K Benzerara, B Kocar, V Chapon, Sequestration of radionuclidesRadium-226 and Strontium-90 by cyanobacteria forming intracellular calcium carbonates, ES&T 2019</p><p>De Wever, A.; Benzerara, K. et al. Evidence of High Ca Uptake by Cyanobacteria Forming Intracellular CaCO 3 and Impact on Their Growth. Geobiology 2019</p><p>Cam, N., Georgelin, T., Jaber, M., Lambert, J.-F., and Benzerara, K, In vitro synthesis of amorphous Mg-, Ca-, Sr- and Ba-carbonates: what do we learn about intracellular calcification by cyanobacteria? Geochim. Cosmochim. Acta 2015</p><p> </p>

Mineral content of honeybee-collected pollen from southern New South Wales

2002 ◽  
Vol 42 (8) ◽  
pp. 1131 ◽  
Author(s):  
D. C. Somerville ◽  
H. I. Nicol
Keyword(s):  
Mineral Content ◽  
New South ◽  
Single Species ◽  
Prunus Dulcis ◽  
High Concentration ◽  
Minor Elements ◽  
South Wales ◽  
Low Concentrations ◽  
The Mean ◽  
Mean Concentration

The mineral content of honeybee-collected pollen from 34 floral species was analysed for 10 elements. The mean concentrations (mg/kg) of major and minor elements were the following: potassium (K) 5530, phosphorus (P) 4600, sulfur (S) 2378, calcium (Ca) 1146, magnesium (Mg) 716, sodium (Na) 82, iron (Fe) 67, zinc�(Zn) 58, manganese (Mn) 33 and copper (Cu) 12. Close correlations existed between Mn and Cu, P and S, K and S and K and Zn. Single species demonstrated similar element profiles. Echium plantagineum pollen had a high mean concentration of P (7411 mg/kg) and S (3133 mg/kg) when compared with the mean of the total; Brassica�napus pollen had high concentration of Mg (1400 mg/kg) and Ca (1750 mg/kg) and low concentration of Fe (27 mg/kg); Hypochoeris radicata had low concentrations of 6 elements — Fe (4.5 mg/kg), Zn (20 mg/kg), Mg�(240 mg/kg), S (1400 mg/kg), P (2066 mg/kg) and K (2433 mg/kg). Asphodelus fistulosus had the highest concentration of K at 38 000 mg/kg, the next highest value of 8200 mg/kg being for Prunus dulcis.

scholarly journals Larval culture and settlement of the intertidal gastropod Siphonaria australis

2021 ◽  
Author(s):  
◽  
Stephanie Marinus
Keyword(s):  
Current Knowledge ◽  
Larval Settlement ◽  
Larval Growth ◽  
Coralline Algae ◽  
Crustose Coralline Algae ◽  
High Concentration ◽  
Laboratory Rearing ◽  
Growth And Survival ◽  
Laboratory Conditions ◽  
Newly Hatched Larvae

<p>Laboratory rearing studies on the larvae of benthic marine invertebrates are important in providing information on the development of marine species, particularly those with complex life history cycles. Intertidal gastropods of the genus Siphonaria have been well studied in aspects of their physiology, behaviour, ecology, and reproduction. However, to our current knowledge, there are no cases on the successful laboratory rearing, from hatching through to metamorphosis, of larvae within this genus. Siphonariids are a primitive family of basommatophoran limpets in which the majority produce encapsulated embryos that hatch into feeding, planktonic veliger larvae. For such larvae, the quality and quantity of phytoplankton food can strongly affect larval growth, survival, and the ability to settle and metamorphose successfully. The primary aim of this study was to identify the optimal algal feeding diet for culturing the larvae of Siphonaria australis to competence in laboratory conditions, with a focus on algal composition and quantity. Once having defined the preferred feeding conditions, a secondary aim was to successfully culture larvae through to metamorphosis, by identifying the required settlement cue(s).  First, I exposed newly hatched larvae to diets of three different algal compositions (all at a high concentration of 20,000 cells/mL): two unialgal diets of Isochrysis galbana and Pavlova lutheri, and a mixed diet consisting of a 1:1 ratio of both species. The results revealed that, although they grew in all diets, S. australis larvae exhibited highest growth and survival when fed the unialgal I.galbana diet.  In a second experiment, I exposed newly hatched larvae to three different food concentrations of the unialgal I. galbana diet; low (1,000 cells/mL), medium (10,000 cells/mL) and high (20,000 cells/mL). Larval growth and survival were highest when fed a high food concentration, with development and survival severely reduced in low food treatments. At the end of this experiment it was discovered that once larvae grew to ~350µm in length, at an age of approximately one month post-hatching, they began to demonstrate signs of competence and growth rates plateaued.  Finally, I exposed newly hatched larvae to optimum feeding conditions in an attempt to achieve larval settlement using different potential cues. Once larvae began to show signs of competence, they were exposed to five settlement cues: (1) live adults in filtered seawater (FSW), (2) adult-conditioned FSW, (3) rocks in adult-conditioned FSW, (4) rocks in regular FSW, and (5) crustose coralline algae-covered rocks in FSW. Larvae only successfully metamorphosed (i.e. exhibited loss of the larval velum) in treatments containing live adults.  In total, my results provide a successful method in culturing Siphonaria australis larvae in laboratory conditions, as well as determines the cue required to induce settlement and metamorphosis. Not only can this method aid in providing more information on the development of this species, but it may also be applied to other members in this genus as well, and further our knowledge on the overall biology of Siphonariid limpets.</p>

scholarly journals Larval culture and settlement of the intertidal gastropod Siphonaria australis

2021 ◽  
Author(s):  
◽  
Stephanie Marinus
Keyword(s):  
Current Knowledge ◽  
Larval Settlement ◽  
Larval Growth ◽  
Coralline Algae ◽  
Crustose Coralline Algae ◽  
High Concentration ◽  
Laboratory Rearing ◽  
Growth And Survival ◽  
Laboratory Conditions ◽  
Newly Hatched Larvae

<p>Laboratory rearing studies on the larvae of benthic marine invertebrates are important in providing information on the development of marine species, particularly those with complex life history cycles. Intertidal gastropods of the genus Siphonaria have been well studied in aspects of their physiology, behaviour, ecology, and reproduction. However, to our current knowledge, there are no cases on the successful laboratory rearing, from hatching through to metamorphosis, of larvae within this genus. Siphonariids are a primitive family of basommatophoran limpets in which the majority produce encapsulated embryos that hatch into feeding, planktonic veliger larvae. For such larvae, the quality and quantity of phytoplankton food can strongly affect larval growth, survival, and the ability to settle and metamorphose successfully. The primary aim of this study was to identify the optimal algal feeding diet for culturing the larvae of Siphonaria australis to competence in laboratory conditions, with a focus on algal composition and quantity. Once having defined the preferred feeding conditions, a secondary aim was to successfully culture larvae through to metamorphosis, by identifying the required settlement cue(s).  First, I exposed newly hatched larvae to diets of three different algal compositions (all at a high concentration of 20,000 cells/mL): two unialgal diets of Isochrysis galbana and Pavlova lutheri, and a mixed diet consisting of a 1:1 ratio of both species. The results revealed that, although they grew in all diets, S. australis larvae exhibited highest growth and survival when fed the unialgal I.galbana diet.  In a second experiment, I exposed newly hatched larvae to three different food concentrations of the unialgal I. galbana diet; low (1,000 cells/mL), medium (10,000 cells/mL) and high (20,000 cells/mL). Larval growth and survival were highest when fed a high food concentration, with development and survival severely reduced in low food treatments. At the end of this experiment it was discovered that once larvae grew to ~350µm in length, at an age of approximately one month post-hatching, they began to demonstrate signs of competence and growth rates plateaued.  Finally, I exposed newly hatched larvae to optimum feeding conditions in an attempt to achieve larval settlement using different potential cues. Once larvae began to show signs of competence, they were exposed to five settlement cues: (1) live adults in filtered seawater (FSW), (2) adult-conditioned FSW, (3) rocks in adult-conditioned FSW, (4) rocks in regular FSW, and (5) crustose coralline algae-covered rocks in FSW. Larvae only successfully metamorphosed (i.e. exhibited loss of the larval velum) in treatments containing live adults.  In total, my results provide a successful method in culturing Siphonaria australis larvae in laboratory conditions, as well as determines the cue required to induce settlement and metamorphosis. Not only can this method aid in providing more information on the development of this species, but it may also be applied to other members in this genus as well, and further our knowledge on the overall biology of Siphonariid limpets.</p>

scholarly journals Review of Overlandflow Quality in Densely Settled Sub-Urban Areas

2004 ◽  
Vol 11 (2) ◽  
Author(s):  
S Sudarmadji
Keyword(s):  
Urban Area ◽  
Urban Areas ◽  
Open Space ◽  
Chemical Parameters ◽  
High Concentration ◽  
Quality Of Water ◽  
Run Off ◽  
Dispersion Agent ◽  
Physical And Chemical

The study aims to analyse quality of water from overlandflow in the sub-urban area having high of to houses, in the Sinduharjo, Sleman regency. In the sub urban area, the run off originated from paved and impermeable are which is not uniformaly distributed over the area. Run off is iniated from detention storage and overlandflow. Therefore any water pollution of the runoof begin from overlandflow which dissolves constituent within the soil and rock materials. Land cover also determines the dispersion agent of rain water thus the affect the material dissolved in the water. As an input into the catchment system, rainfall affects overlandflow, quantitative, and qualitatively. Overlandflow from open space in the sub-urban area was evaluated based on physical and chemical characteristics. Overlandflow from urban area has chemical parameters such as C, NO2, NO3, and PO4 are higher than those in overlandflow from rural area which is covered by forest and garden. Overlandflow shows BOD and COD in relatively high concentration. Overlandflow is not recomended to be discharge into infiltration wells, unless it is free from parts having high significant contamination.

Cytomembrane Preservation in Tissue Dehydrated Only With Glutaraldehyde and Epon 812 Resin

1973 ◽  
Vol 31 ◽  
pp. 320-321
Author(s):  
Daniel C. Pease
Keyword(s):  
Diffraction Pattern ◽  
X Ray Diffraction ◽  
High Concentration ◽  
Unpublished Study ◽  
X Ray ◽  
Sectioned Material

A previous study demonstrated that tissue could be successfully infiltrated with 50% glutaraldehyde, and then subsequently polymerized with urea to create an embedment which retained cytomembrane lipids in sectioned material. As a result, the 180-190 Å periodicity characteristic of fresh, mammalian myelin was preserved in sections, as was a brilliant birefringence, and the capacity to bind OsO4 vapor in the hydrophobic bilayers. An associated (unpublished) study, carried out in co-operation with Drs. C.K. Akers and D.F. Parsons, demonstrated that the high concentration of glutaraldehyde (and urea) did not significantly alter the X-ray diffraction pattern of aldehyde-fixed, myelin. Thus, by itself, 50% glutaraldehyde has little effect upon cytomembrane systems and can be used with confidence for the first stages of dehydration.

High Resolution Observations of Ion-Milling Induced Transformation in Synthetic Hollandses

1981 ◽  
Vol 39 ◽  
pp. 114-115 ◽  
Author(s):  
T. J. Headley
Keyword(s):  
High Resolution ◽  
Radioactive Waste Disposal ◽  
Ion Milling ◽  
Minor Elements ◽  
Waste Forms ◽  
Carbon Substrates ◽  
Structural Differences ◽  
Oxide Phases ◽  
Argon Ions ◽  
High Resolution Microscopy

Oxide phases having the hollandite structure have been identified in multiphase ceramic waste forms being developed for radioactive waste disposal. High resolution studies of phases in the waste forms described in Ref. [2] were initiated to examine them for fine scale structural differences compared to natural mineral analogs. Two hollandites were studied: a (Ba,Cs,K)-titan-ate with minor elements in solution that is produced in the waste forms, and a synthesized BaAl2Ti6O16 phase containing ∼ 4.7 wt% Cs2O. Both materials were consolidated by hot pressing at temperatures above 1100°C. Samples for high resolution microscopy were prepared both by ion-milling (7kV argon ions) and by crushing and dispersing the fragments on holey carbon substrates. The high resolution studies were performed in a JEM 200CX/SEG operating at 200kV.

Effects of carbamylcholine on chick embryo aggregate retina cell cultures

1988 ◽  
Vol 46 ◽  
pp. 350-351
Author(s):  
Glenn M. Cohen ◽  
Radharaman Ray
Keyword(s):  
Cell Cultures ◽  
Single Cells ◽  
Retinal Cell ◽  
Cell Aggregates ◽  
High Concentration ◽  
In Ovo ◽  
Sterile Culture ◽  
Retinal Tissue ◽  
Synaptic Junctions ◽  
And Control

Retinal,cell aggregates develop in culture in a pattern similar to the in ovo retina, forming neurites first and then synapses. In the present study, we continuously exposed chick retinal cell aggregates to a high concentration (1 mM) of carbamylcholine (carbachol), an acetylcholine (ACh) analog that resists hydrolysis by acetylcholinesterase (AChE). This situation is similar to organophosphorus anticholinesterase poisoning in which the ACh level is elevated at synaptic junctions due to inhibition of AChE, Our objective was to determine whether continuous carbachol exposure either damaged cholino- ceptive neurites, cell bodies, and synaptic elements of the aggregates or influenced (hastened or retarded) their development.The retinal tissue was isolated aseptically from 11 day embryonic White Leghorn chicks and then enzymatically (trypsin) and mechanically (trituration) dissociated into single cells. After washing the cells by repeated suspension and low (about 200 x G) centrifugation twice, aggregate cell cultures (about l0 cells/culture) were initiated in 1.5 ml medium (BME, GIBCO) in 35 mm sterile culture dishes and maintained as experimental (containing 10-3 M carbachol) and control specimens.

The Fine Structure of Phloem Cells

1985 ◽  
Vol 43 ◽  
pp. 632-635
Author(s):  
James Cronshaw
Keyword(s):  
Structural Studies ◽  
High Concentration ◽  
Long Distance ◽  
Phloem Tissue ◽  
Sieve Elements ◽  
Long Distance Transport ◽  
P Protein ◽  
Companion Cells ◽  
Electron Microscopical ◽  
Distance Transport

Long distance transport in plants takes place in phloem tissue which has characteristic cells, the sieve elements. At maturity these cells have sieve areas in their end walls with specialized perforations. They are associated with companion cells, parenchyma cells, and in some species, with transfer cells. The protoplast of the functioning sieve element contains a high concentration of sugar, and consequently a high hydrostatic pressure, which makes it extremely difficult to fix mature sieve elements for electron microscopical observation without the formation of surge artifacts. Despite many structural studies which have attempted to prevent surge artifacts, several features of mature sieve elements, such as the distribution of P-protein and the nature of the contents of the sieve area pores, remain controversial.

Tem analysis of multiple-energy arsenic implanted and Rta'd silicon

1987 ◽  
Vol 45 ◽  
pp. 246-247
Author(s):  
R.A. Herring
Keyword(s):  
Device Fabrication ◽  
High Concentration ◽  
Tem Analysis ◽  
Defect Clusters ◽  
High Fluences ◽  
Small Defect ◽  
Before And After ◽  
The Matrix ◽  
The Difference ◽  
Factor Type

Rapid thermal annealing (RTA) of ion-implanted Si is important for device fabrication. The defect structures of 2.5, 4.0, and 6.0 MeV As-implanted silicon irradiated to fluences of 2E14, 4E14, and 6E14, respectively, have been analyzed by electron diffraction both before and after RTA at 1100°C for 10 seconds. At such high fluences and energies the implanted As ions change the Si from crystalline to amorphous. Three distinct amorphous regions emerge due to the three implantation energies used (Fig. 1). The amorphous regions are separated from each other by crystalline Si (marked L1, L2, and L3 in Fig. 1) which contains a high concentration of small defect clusters. The small defect clusters were similar to what had been determined earlier as being amorphous zones since their contrast was principally of the structure-factor type that arises due to the difference in extinction distance between the matrix and damage regions.

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