Spatial distribution and quantification of Fucus species and Ascophyllum nodosum beds in intertidal zones using spot imagery

Abstract On the southeastern Tunisian coastline, very diverse living microbial mats colonize the lower supratidal and intertidal zones, and locally may extend into the upper infratidal zone. The interaction between the benthic cyanobacteria and their siliciclastic substratum leads to the development of several types of microbially induced sedimentary structures (MISS). The mapping of the microbial mats has allowed the identification of the types of MISS that characterize the different segments of the coastal environment. The modern microbial mats have been compared with those recorded at the top of the Holocene deposits, which are composed of biodegraded microbial black mats alternating with white laminae made of clastic and evaporitic sediments, indicative of very high frequency cycles of flood and drought. A hypothetic profile showing their occurrences along the different areas bordering the coastline is proposed as a guide for the reconstruction of the ancient depositional environment. The roles of tidal dynamics, storms, and climate in controlling their genesis and spatial distribution, are discussed and highlighted. The modern MISS of southeastern Tunisia are compared with their equivalents that are well documented through the different geological eras.

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The intertidal gastropods (Gastropoda: Mollusca) diversity and taxa distribution in Alas Purwo National Park, East Java, Indonesia

Biodiversitas Journal of Biological Diversity ◽

10.13057/biodiv/d200731 ◽

2019 ◽

Vol 20 (7) ◽

Author(s):

SUSINTOWATI SUSINTOWATI ◽

NYOMAN PUNIAWATI ◽

ERNY POEDJIRAHAJOE ◽

NIKEN SATUTI NUR HANDAYANI ◽

SUWARNO HADISUSANTO

Keyword(s):

Spatial Distribution ◽

Distribution Pattern ◽

National Park ◽

Diversity Index ◽

Principal Component ◽

Spatial Distribution Pattern ◽

Intertidal Zones ◽

Diverse Environment ◽

Morisita Index ◽

Diversity Profile

Abstract. Susintowati, Puniawati N, Poedjirahajoe, Handayani NSN, Hadisusanto S. 2019. The intertidal gastropods (Gastropoda: Mollusca) diversity and taxa distribution in Alas Purwo National Park, East Java, Indonesia. Biodiversitas 20: 2016-2027. Gastropods play an essential role in the ecosystem and can be used as bioindicators of environmental pollution. Understanding of their behavior, habitat, and distribution, and how these factors evolve, is crucial. This paper aimed to describe the diversity of the gastropod community and their spatial taxa distribution, based on the specimen frequency across all observed samples, in the diverse environment of Alas Purwo National Park (APNP), East Java, Indonesia. We studied eight beaches and two mangroves areas, and the study areas of the intertidal zone divided into upper, middle, and lower zones towards the sea. The purposive sampling was used to determine the locations and multi-plot quadrats for observations. The diversity of gastropods was elucidated by using the Shannon and Simpson indexes, while the Morisita index was applied for analyzing their spatial distribution pattern. However, the correspondence analysis and principal component analysis were performed using the software of PAST 3.22 for describing the diversity profile and individual rarefaction of gastropods together with environmental quality. There were three beach types: rocky, sandy, and muddy beaches were found in APNP. The highest diversity index (H’) was found on Pancur beach: H’ = 3.271, D = 0.947 of 67 species. The spatial distribution pattern of gastropods species was weakly clumped to random, with Ip: 0.165 - 0.016. Gastropods, both predators and scavengers, were distributed from the upper to lower zones. The distribution of gastropods in APNP is mostly in type B. These results expand our knowledge of gastropods diversity and distribution of Indonesia’s beach and can contribute to the future environmental assessments of biodiversity of tropical intertidal zones worldwide.

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Immune electron microscopy of haemocyanins from two southern african whelks

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100081656 ◽

1978 ◽

Vol 36 (2) ◽

pp. 158-159

Author(s):

Linda M. Stannard ◽

Margaret Lennon

Keyword(s):

Electron Microscopy ◽

Electron Microscope ◽

Outer Ring ◽

Immune Electron Microscopy ◽

Intertidal Zones ◽

Central Belt ◽

Cape Peninsula ◽

Circular Contour

Burnupena cincta and Fusus verruculatus are two whelks which inhabit the intertidal zones of the Cape Peninsula shore. Their respiratory pigments, or haemocyanins, are morphologically similar in structure (Figs. 1 and 2) and appear in the electron microscope as short cylindrical rods about 34 nm in diameter and 36 nm high. Viewed side-on the molecules show regular banding suggesting a structure composed of six equidistant rings of sub-units. Occasionally the particles have the appearance of possessing a central “belt” in the position of the 3rd and 4th rows of sub-units. End-on views of the haemocyanin molecules show a circular contour with a dense outer ring and a less dense inner ring in which 10 definite sub-units may frequently be distinguished. A number of molecules display an extra central inner component which appears either as a diffuse plug or as a discrete ring-shaped core ± 8 nm in diameter.

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Lithography below 100 nm

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100074367 ◽

1983 ◽

Vol 41 ◽

pp. 96-99

Author(s):

L. D. Jackel

Keyword(s):

Spatial Distribution ◽

Electron Beam ◽

Electron Scattering ◽

Electron Beam Lithography ◽

Substrate Material ◽

Local Electron ◽

Electron Dose ◽

Positive Resist ◽

Exposure Process

Most production electron beam lithography systems can pattern minimum features a few tenths of a micron across. Linewidth in these systems is usually limited by the quality of the exposing beam and by electron scattering in the resist and substrate. By using a smaller spot along with exposure techniques that minimize scattering and its effects, laboratory e-beam lithography systems can now make features hundredths of a micron wide on standard substrate material. This talk will outline sane of these high- resolution e-beam lithography techniques.We first consider parameters of the exposure process that limit resolution in organic resists. For concreteness suppose that we have a “positive” resist in which exposing electrons break bonds in the resist molecules thus increasing the exposed resist's solubility in a developer. Ihe attainable resolution is obviously limited by the overall width of the exposing beam, but the spatial distribution of the beam intensity, the beam “profile” , also contributes to the resolution. Depending on the local electron dose, more or less resist bonds are broken resulting in slower or faster dissolution in the developer.

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SEM evaluation of the TEM cold-stage double-film specimen

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100111471 ◽

1984 ◽

Vol 42 ◽

pp. 272-273

Author(s):

Jayesh Bellare

Keyword(s):

Spatial Distribution ◽

Sample Preparation ◽

Sample Thickness ◽

Specimen Preparation ◽

Preparation Technique ◽

Liquid Sample ◽

Thin Specimen ◽

Sample Preparation Technique ◽

Cold Stage ◽

Film Specimen

Seeing is believing, but only after the sample preparation technique has received a systematic study and a full record is made of the treatment the sample gets.For microstructured liquids and suspensions, fast-freeze thermal fixation and cold-stage microscopy is perhaps the least artifact-laden technique. In the double-film specimen preparation technique, a layer of liquid sample is trapped between 100- and 400-mesh polymer (polyimide, PI) coated grids. Blotting against filter paper drains excess liquid and provides a thin specimen, which is fast-frozen by plunging into liquid nitrogen. This frozen sandwich (Fig. 1) is mounted in a cooling holder and viewed in TEM.Though extremely promising for visualization of liquid microstructures, this double-film technique suffers from a) ireproducibility and nonuniformity of sample thickness, b) low yield of imageable grid squares and c) nonuniform spatial distribution of particulates, which results in fewer being imaged.

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Macroprobe Mode for the Study of Segregation in Steels

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100134909 ◽

1990 ◽

Vol 48 (2) ◽

pp. 260-261

Author(s):

Auclair Gilles ◽

Benoit Danièle

Keyword(s):

Mechanical Properties ◽

Spatial Distribution ◽

High Performance ◽

Volume Fraction ◽

Sheet Steel ◽

Acquisition Time ◽

Chemical Information ◽

X Ray ◽

Accurate Quantitative Analysis ◽

Optical Micrographs

During these last 10 years, high performance correction procedures have been developed for classical EPMA, and it is nowadays possible to obtain accurate quantitative analysis even for soft X-ray radiations. It is also possible to perform EPMA by adapting this accurate quantitative procedures to unusual applications such as the measurement of the segregation on wide areas in as-cast and sheet steel products.The main objection for analysis of segregation in steel by means of a line-scan mode is that it requires a very heavy sampling plan to make sure that the most significant points are analyzed. Moreover only local chemical information is obtained whereas mechanical properties are also dependant on the volume fraction and the spatial distribution of highly segregated zones. For these reasons we have chosen to systematically acquire X-ray calibrated mappings which give pictures similar to optical micrographs. Although mapping requires lengthy acquisition time there is a corresponding increase in the information given by image anlysis.

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Ultrastructural analysis of the spatial distribution of MRNA

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100123167 ◽

1992 ◽

Vol 50 (1) ◽

pp. 552-553

Author(s):

Gary Bassell ◽

Robert H. Singer

Keyword(s):

Electron Microscopy ◽

Spatial Distribution ◽

In Situ Hybridization ◽

High Resolution ◽

Nucleic Acids ◽

Colloidal Gold ◽

Dna Probe ◽

Nucleotide Analogs ◽

Gold Particles

We have been investigating the spatial distribution of nucleic acids intracellularly using in situ hybridization. The use of non-isotopic nucleotide analogs incorporated into the DNA probe allows the detection of the probe at its site of hybridization within the cell. This approach therefore is compatible with the high resolution available by electron microscopy. Biotinated or digoxigenated probe can be detected by antibodies conjugated to colloidal gold. Because mRNA serves as a template for the probe fragments, the colloidal gold particles are detected as arrays which allow it to be unequivocally distinguished from background.

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Membrane microdomains: lessons from microscopy

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100140257 ◽

1995 ◽

Vol 53 ◽

pp. 776-777

Author(s):

J.M. Robinson ◽

J.M Oliver

Keyword(s):

Spatial Distribution ◽

Plasma Membrane ◽

Epithelial Cells ◽

Plasma Membranes ◽

Cell Types ◽

Imaging Modalities ◽

Membrane Microdomains ◽

Membrane Domains ◽

Lateral Heterogeneity ◽

Functional Importance

Specialized regions of plasma membranes displaying lateral heterogeneity are the focus of this Symposium. Specialized membrane domains are known for certain cell types such as differentiated epithelial cells where lateral heterogeneity in lipids and proteins exists between the apical and basolateral portions of the plasma membrane. Lateral heterogeneity and the presence of microdomains in membranes that are uniform in appearance have been more difficult to establish. Nonetheless a number of studies have provided evidence for membrane microdomains and indicated a functional importance for these structures.This symposium will focus on the use of various imaging modalities and related approaches to define membrane microdomains in a number of cell types. The importance of existing as well as emerging imaging technologies for use in the elucidation of membrane microdomains will be highlighted. The organization of membrane microdomains in terms of dimensions and spatial distribution is of considerable interest and will be addressed in this Symposium.

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An analytical microscopic study of metals in fluidized catalytic cracking catalyst

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100145613 ◽

1986 ◽

Vol 44 ◽

pp. 854-855

Author(s):

Clifford S. Rainey

Keyword(s):

Electron Microscopy ◽

Spatial Distribution ◽

Catalytic Cracking ◽

Catalyst Deactivation ◽

Coke Formation ◽

Acid Sites ◽

Y Zeolite ◽

Fcc Catalyst ◽

Fluidized Catalytic Cracking ◽

High Regeneration

The spatial distribution of V and Ni deposited within fluidized catalytic cracking (FCC) catalyst is studied because these metals contribute to catalyst deactivation. Y zeolite in FCC microspheres are high SiO2 aluminosilicates with molecular-sized channels that contain a mixture of lanthanoids. They must withstand high regeneration temperatures and retain acid sites needed for cracking of hydrocarbons, a process essential for efficient gasoline production. Zeolite in combination with V to form vanadates, or less diffusion in the channels due to coke formation, may deactivate catalyst. Other factors such as metal "skins", microsphere sintering, and attrition may also be involved. SEM of FCC fracture surfaces, AEM of Y zeolite, and electron microscopy of this work are developed to better understand and minimize catalyst deactivation.

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