Cyanobacteria-shrimp colonies in the Mariana Islands

AbstractCyanobacteria have multifaceted ecological roles on coral reefs. Moorena bouillonii, a chemically rich filamentous cyanobacterium, has been characterized as a pathogenic organism with an unusual ability to overgrow gorgonian corals, but little has been done to study its general growth habits or its unique association with the snapping shrimp Alpheus frontalis. Quantitative benthic surveys, and field and photographic observations were utilized to develop a better understanding of the ecology of these species, while growth experiments and nutrient analysis were performed to examine how this cyanobacterium may be benefiting from its shrimp symbiont. Colonies of M. bouillonii and A. frontalis displayed considerable habitat specificity in terms of occupied substrate. Although found to vary in abundance and density across survey sites and transects, M. bouillonii was consistently found to be thriving with A. frontalis within interstitial spaces on the reef. Removal of A. frontalis from cyanobacterial colonies in a laboratory experiment altered M. bouillonii pigmentation, whereas cyanobacteria-shrimp colonies in the field exhibited elevated nutrient levels compared to the surrounding seawater.

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Effect of light intensity on the ultrastructure of the filamentous cyanobacterium, Anabaena variabilis

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100103565 ◽

1988 ◽

Vol 46 ◽

pp. 300-301

Author(s):

C. S. Bricker ◽

S. R. Barnum ◽

B. Huang ◽

J. G. Jaworskl

Keyword(s):

Fatty Acid ◽

Light Intensity ◽

Acid Content ◽

Fatty Acid Content ◽

Anabaena Variabilis ◽

Chloroplast Envelope ◽

Major Constituent ◽

Filamentous Cyanobacterium ◽

Photosynthetic Membrane ◽

Effect Of Light

Cyanobacteria are Gram negative prokaryotes that are capable of oxygenic photosynthesis. Although there are many similarities between eukaryotes and cyanobacteria in electron transfer and phosphorylation during photosynthesis, there are two features of the photosynthetic apparatus in cyanobacteria which distinguishes them from plants. Cyanobacteria contain phycobiliproteins organized in phycobilisomes on the surface of photosynthetic membrane. Another difference is in the organization of the photosynthetic membranes. Instead of stacked thylakolds within a chloroplast envelope membrane, as seen In eukaryotes, IntracytopIasmlc membranes generally are arranged in three to six concentric layers. Environmental factors such as temperature, nutrition and light fluency can significantly affect the physiology and morphology of cells. The effect of light Intensity shifts on the ultrastructure of Internal membrane in Anabaena variabilis grown under controlled environmental conditions was examined. Since a major constituent of cyanobacterial thylakolds are lipids, the fatty acid content also was measured and correlated with uItrastructural changes. The regulation of fatty acid synthesis in cyanobacteria ultimately can be studied if the fatty acid content can be manipulated.

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The effect of back-melting on the continuity of crystallographic orientation and composition in HgZnTe

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100133114 ◽

1992 ◽

Vol 50 (2) ◽

pp. 1696-1697

Author(s):

H.J. Zuo ◽

M.W. Price ◽

R.D. Griffin ◽

R.A. Andrews ◽

G.M. Janowski

Keyword(s):

Directional Solidification ◽

Space Shuttle ◽

Solidification Process ◽

Space Experiment ◽

Infrared Detection ◽

Directionally Solidified ◽

Crystallographic Defects ◽

Semiconducting Alloys ◽

Uniform Composition ◽

Growth Experiments

The II-VI semiconducting alloys, such as mercury zinc telluride (MZT), have become the materials of choice for numerous infrared detection applications. However, compositional inhomogeneities and crystallographic imperfections adversly affect the performance of MZT infrared detectors. One source of imperfections in MZT is gravity-induced convection during directional solidification. Crystal growth experiments conducted in space should minimize gravity-induced convection and thereby the density of related crystallographic defects. The limited amount of time available during Space Shuttle experiments and the need for a sample of uniform composition requires the elimination of the initial composition transient which occurs in directionally solidified alloys. One method of eluding this initial transient involves directionally solidifying a portion of the sample and then quenching the remainder prior to the space experiment. During the space experiment, the MZT sample is back-melted to exactly the point at which directional solidification was stopped on earth. The directional solidification process then continues.

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Scanning Transmission Electron Microscopy of Polyethylene Crystals

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s1431927600001069 ◽

1980 ◽

Vol 38 ◽

pp. 242-245

Author(s):

F. Khoury ◽

L. H. Bolz

Keyword(s):

Electron Microscopy ◽

Transmission Electron Microscopy ◽

Crystallization Temperature ◽

Scanning Transmission Electron Microscopy ◽

Growth Habit ◽

Lateral Growth ◽

Scanning Transmission Electron ◽

Transmission Electron ◽

Scanning Transmission ◽

Growth Habits

The lateral growth habits and non-planar conformations of polyethylene crystals grown from dilute solutions (<0.1% wt./vol.) are known to vary depending on the crystallization temperature.1-3 With the notable exception of a study by Keith2, most previous studies have been limited to crystals grown at <95°C. The trend in the change of the lateral growth habit of the crystals with increasing crystallization temperature (other factors remaining equal, i.e. polymer mol. wt. and concentration, solvent) is illustrated in Fig.l. The lateral growth faces in the lozenge shaped type of crystal (Fig.la) which is formed at lower temperatures are {110}. Crystals formed at higher temperatures exhibit 'truncated' profiles (Figs. lb,c) and are bound laterally by (110) and (200} growth faces. In addition, the shape of the latter crystals is all the more truncated (Fig.lc), and hence all the more elongated parallel to the b-axis, the higher the crystallization temperature.

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Northern Mariana Islands Drug Threat Assessment

PsycEXTRA Dataset ◽

10.1037/e568672006-001 ◽

2003 ◽

Keyword(s):

Threat Assessment ◽

Mariana Islands ◽

Northern Mariana Islands

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Possible Werner syndrome. A unique association with spontaneous digital gangrene in infancy and decreased life span of cultured skin fibroblasts

Archives of Dermatology ◽

10.1001/archderm.128.9.1238 ◽

1992 ◽

Vol 128 (9) ◽

pp. 1238-1242 ◽

Cited By ~ 1

Author(s):

S. Iijima

Keyword(s):

Life Span ◽

Werner Syndrome ◽

Skin Fibroblasts ◽

Cultured Skin ◽

Unique Association

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Preparation of Banana Residue Based Compost and its Nutrient Analysis

SINDH UNIVERSITY RESEARCH JOURNAL -SCIENCE SERIES ◽

10.26692/surj/2019.09.89 ◽

2019 ◽

Vol 51 (03) ◽

pp. 569--572

Author(s):

S. A. ABRO ◽

Z.A. CHANNA ◽

M. GADEHI ◽

A. A. ABRO ◽

S. P. TUNIO ◽

...

Keyword(s):

Nutrient Analysis

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What habitat does spiny snout mite occupy in Tasmania

New Zealand Plant Protection ◽

10.30843/nzpp.2015.68.5854 ◽

2015 ◽

Vol 68 ◽

pp. 446-446

Author(s):

D.J. Wilson ◽

P.J. Gerard

Keyword(s):

New Zealand ◽

Sand Dune ◽

Biocontrol Agent ◽

Predatory Mites ◽

Mite Species ◽

Predatory Mite ◽

Habitat Specificity ◽

Nontarget Organisms ◽

Flea Control ◽

Potential Biocontrol Agent

Spiny snout mite (Neomolgus capillatus) is a potential biocontrol agent for clover flea (Sminthurus viridis) a white clover pest on dairy farms in warmer and wetter parts of New Zealand In the 1990s this mite was introduced from Brittany France into Tasmania for clover flea control Results during the release programme were highly promising and subsequent anecdotal farmer reports indicate widespread decreases in damage As N capillatus is a predatory mite and already known to attack nontarget organisms habitat specificity will determine whether it could be introduced into New Zealand without risk to native insects To assess this pastures on nine of the original Tasmanian release farms and adjacent nontarget habitats ranging from bush wetlands eucalypt stands to sand dune country were sampled in April 2014 Litter samples were collected heat extracted and mite species identified Neomolgus capillatus was found at effective densities in pastures that had good clover cover Where present it displaced Bdellodes spp mites that are ineffective against clover flea No N capillatus were found in the nontarget habitats all of which lacked clover and contained other predatory mites including Bdellodes spp Therefore the preference by N capillatus for lush pastures makes it an excellent prospect for introduction as a biocontrol agent into clover flea prone regions of New Zealand

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