Host specificity and feeding in European pea crabs (Brachyura, Pinnotheridae)

Crustaceana ◽  
2017 ◽  
Vol 90 (7-10) ◽  
pp. 819-844 ◽  
Author(s):  
Carola Becker ◽  
Michael Türkay
Keyword(s):  
Host Specificity ◽  
Food Source ◽  
Host Choice ◽  
Feeding Strategies ◽  
Pinna Nobilis ◽  
Morphological Adaptations ◽  
Pen Shell ◽  
Scanning Electron ◽  
Host Relations

Pinnotherids, or pea crabs, are symbionts of invertebrates used for shelter and as food source. Feeding strategies and morphological adaptations to food uptake are important to understand host relations and how the host specificity is determined. We herein re-examine the host range of pinnotherids based on long-term collections from different localities in European waters. Both species of Pinnotheres are restricted to bivalves. Pinnotheres pisum infests mussels, oysters, the noble pen shell Pinna nobilis and other bivalves. Pinnotheres pectunculi is symbiotic with Glycymeris glycymeris and several other species of venerids. Nepinnotheres pinnotheres infests ascidians and Pinna nobilis. Observations on feeding in Pinnotheres reveal how mucus strings are brushed from the host gills with a setal comb in the chelipeds, which we describe by using scanning electron microscopy. Our observations on feeding structures are discussed in relation to the host specificity of each species and compared to other pinnotherid taxa, taking additional factors of host choice into account.

SEM Observations on the Germination of Euonymous Americanus

1985 ◽  
Vol 43 ◽  
pp. 508-509
Author(s):  
D.R. Hill ◽  
J.R. McCurry ◽  
L.P. Elliott ◽  
G. Howard
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Light Microscopy ◽  
Filter Paper ◽  
Room Temperature ◽  
Food Source ◽  
Environmental Chamber ◽  
Dormant Stage ◽  
Scanning Electron

Germination of Euonymous americanus in the laboratory has previously been unsuccessful. Ability to germinate Euonymous americanus. commonly known as the american strawberry bush, is important in that it represents a valuable food source for the white-tailed deer. Utilizing the knowledge that its seeds spend a period of time in the rumin fluid of deer during their dormant stage, we were successful in initiating germination. After a three month drying period, the seeds were placed in 25 ml of buffered rumin fluid, pH 8 at 40°C for 48 hrs anaerobically. They were then allowed to dry at room temperature for 24 hrs, placed on moistened filter paper and enclosed within an environmental chamber. Approximately four weeks later germination was detected and verified by scanning electron microscopy; light microscopy provided inadequate resolution. An important point to note in this procedure is that scarification, which was thought to be vital for germination, proved to be unnecessary for successful germination to occur. It is believed that germination was propagated by the secretion of enzymes or prescence of acids produced by microorganisms found in the rumin fluid since sterilized rumin failed to bring about germination.

scholarly journals Using Fission-Track Radiography Coupled with Scanning Electron Microscopy for Efficient Identification of Solid-Phase Uranium Mineralogy at a Former Uranium Pilot Mill (Grand Junction, Colorado)

Geosciences ◽  
2021 ◽  
Vol 11 (7) ◽  
pp. 294
Author(s):  
Raymond H. Johnson ◽  
Susan M. Hall ◽  
Aaron D. Tigar
Keyword(s):  
Fission Track ◽  
Solid Phase ◽  
Nuclear Research ◽  
Thin Sections ◽  
Nuclear Research Reactor ◽  
Elemental Data ◽  
Individual Grains ◽  
Scanning Electron ◽  
Section Sample

At a former uranium pilot mill in Grand Junction, Colorado, mine tailings and some subpile sediments were excavated to various depths to meet surface radiological standards, but residual solid-phase uranium below these excavation depths still occurs at concentrations above background. The combination of fission-track radiography and scanning electron microscope energy-dispersive X-ray spectroscopy (SEM-EDS) provides a uniquely efficient and quantitative way of determining mineralogic associations of uranium that can influence uranium mobility. After the creation of sample thin sections, a mica sheet is placed on those thin sections and irradiated in a nuclear research reactor. Decay of the irradiated uranium creates fission tracks that can be viewed with a microscope. The fission-track radiography images indicate thin section sample areas with elevated uranium that are focus areas for SEM-EDS work. EDS spectra provide quantitative elemental data that indicate the mineralogy of individual grains or grain coatings associated with the fission-track identification of elevated uranium. For the site in this study, the results indicated that uranium occurred (1) with coatings of aluminum–silicon (Al/Si) gel and gypsum, (2) dispersed in the unsaturated zone associated with evaporite-type salts, and (3) sorbed onto organic carbon. The Al/Si gel likely formed when low-pH waters were precipitated during calcite buffering, which in turn retained or precipitated trace amounts of Fe, As, U, V, Ca, and S. Understanding these mechanisms can help guide future laboratory and field-scale efforts in determining long-term uranium release rates to groundwater.

Host specificity of Argulus coregoni (Crustacea: Branchiura) increases at maturation

Parasitology ◽  
2007 ◽  
Vol 134 (12) ◽  
pp. 1767-1774 ◽  
Author(s):  
V. N. MIKHEEV ◽  
A. F. PASTERNAK ◽  
E. T. VALTONEN
Keyword(s):  
Host Specificity ◽  
Host Preference ◽  
Oxygen Depletion ◽  
Host Choice ◽  
Fish Host ◽  
Argulus Foliaceus ◽  
Argulus Coregoni ◽  
Suitable Habitats ◽  
Fish Hosts ◽  
Higher Sensitivity

SUMMARYWe tested the hypothesis that host specificity in ectoparasites does not depend exclusively on the features of the host but also on surrounding habitats, using 2 fish ectoparasites, Argulus coregoni and A. foliaceus (Crustacea: Branchiura), occurring sympatrically in Finnish lakes. Although these parasites are considered to be of low specificity, we found that the larger of the 2 species, A. coregoni developed a pronounced preference for salmonid hosts at the beginning of maturation (defined by the presence of copulating specimens). Argulus foliaceus infects a much wider range of fish hosts. We showed that specialization of A. coregoni on salmonids does not necessarily result from incompatibility with other fishes, but could instead reflect higher sensitivity of oxygen depletion compared with A. foliaceus. Adult A. coregoni may meet these demands by attaching to salmonids, the typical inhabitants of well-aerated waters. Young parasites of both species showed little host specificity and attached mainly to fishes with higher body reflectivity. In host choice experiments, A. coregoni of 4–5 mm length preferred salmonids (rainbow trout) to cyprinids (roach) irrespective of the type of fish host, on which it had been previously grown in the laboratory. We suggest that such an innate ontogenetic shift in host preference maintains the major part of the parasite population on its principal host, ensuring successful reproduction within suitable habitats.

Guilielmia Weise, a little known Afrotropical flea beetle genus: systematic affinities and description of a second new species from Central Africa (Coleoptera, Chrysomelidae, Galerucinae, Alticini)

Zootaxa ◽  
2017 ◽  
Vol 4323 (4) ◽  
pp. 572 ◽  
Author(s):  
MAURIZIO BIONDI ◽  
PAOLA D’ALESSANDRO
Keyword(s):  
New Species ◽  
Electron Micrographs ◽  
Type Species ◽  
Flea Beetle ◽  
Central Africa ◽  
Scanning Electron Micrographs ◽  
Female Specimen ◽  
High Mountains ◽  
Morphological Adaptations ◽  
Scanning Electron

The genus Guilielmia Weise from the high mountains of Central Africa, known on a female specimen only, is redescribed based on new specimens of the type species, and the new species Guilielmia leleupi sp. nov. described here. Habitus photos, and microscope and scanning electron micrographs of diagnostic characters, including the aedeagus, are provided for both the species. Some considerations about taxonomic affinities and morphological adaptations to high altitudes are suggested. 

scholarly journals Preparation and Characterization of PEBAX-5513/AgBF4/BMIMBF4 Membranes for Olefin/Paraffin Separation

Polymers ◽  
2020 ◽  
Vol 12 (7) ◽  
pp. 1550 ◽  
Author(s):  
So Young Kim ◽  
Younghyun Cho ◽  
Sang Wook Kang
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Poor Performance ◽  
Amide Group ◽  
Stabilizing Effect ◽  
Poly Ethylene Oxide ◽  
Poly Ethylene ◽  
Scanning Electron

In this study, we investigated a poly(ether-block-amide)-5513 (PEBAX-5513)/AgBF4/1-butyl-3-methylimidazolium tetrafluoroborate (BMIMBF4) composite membrane, which is expected to have a high stabilizing effect on the Ag+ ions functioning as olefin carriers in the amide group. Poly(ethylene oxide) (PEO) only consists of ether regions, whereas the PEBAX-5513 copolymer contains both ether and amide regions. However, given the brittle nature of the amide, the penetration of BMIMBF4 remains challenging. The nanoparticles did not stabilize after their formation in the long-term test, thereby resulting in a poor performance compared to previous experiments using PEO as the polymer (selectivity 3; permeance 12.3 GPU). The properties of the functional groups in the polymers were assessed using Fourier transform infrared spectroscopy, scanning electron microscopy, and thermogravimetric analysis, which confirmed that the properties endowed during the production of the film using the ionic liquid can impact the performance.

scholarly journals Biologia de Phyllostomus hastatus (Pallas, 1767) (Chiroptera, Mammalia) em dois parques urbanos no Estado do Rio de Janeiro, Brasil

2019 ◽  
Vol 20 (1) ◽  
pp. 1-13
Author(s):  
Isabel Cardim De Resende ◽  
Patrícia Gonçalves Guedes ◽  
Shirley Seixas Pereira Da Silva ◽  
Alexandre Maurício Carneiro
Keyword(s):  
Rio De Janeiro ◽  
Food Source ◽  
Small Animals ◽  
Fecal Material ◽  
Ecological Corridor ◽  
Blood Smears ◽  
Phyllostomus Hastatus ◽  
Janeiro City

Studies about bats biology encompassing diet, reproduction and parasitology are important to understand the role of these small animals in the ecosystem. However, few studies present such information. Therefore, the present paper was made to congregate information about biology of Phyllostomus hastatus, and compare the results between two urban parks at Rio de Janeiro City (Rio de Janeiro, Brazil): Parque Natural Municipal da Freguesia (PNMF) and Parque Estadual da Pedra Branca (PEPB), the latter being considerably larger than the other one. Long-term fieldworks were conducted in both areas and data on biometry, reproduction, parasites and diet were assembled. Animals were captured in mists nets and put in cotton sacs, from where fecal material was collected for further analysis. They were measured alive and inspected for reproductive stage; ectoparasites were collected and blood smears were made whenever possible. Bats were released at the end of the fieldwork. The feces and blood material were analyzed at the lab. Thus, 53 specimens of Phyllostomus were captured, 13 from PNMF and 40 from PEPB. We found individuals with smaller measurements at the most anthropized park – the Freguesia Park; reproduction occurred between September and December at both parks; diet included Curcubitaceae, Urticaceae, Bombacaceae, Lythraceae, Coleoptera, Lepidoptera, Hemiptera and Diptera. Concerning ectoparasites, Diptera and Acari were recorded; no haemoparasites were found in the blood smears. Although specimens from the smaller park seem to be most affected by anthropization, our results reinforce the idea that the creation of small parks is important for species maintenance, since it may serve as ecological corridor and as a food source for the animals.

Effect of Double-Step Solution Treatment on Rejuvenation Heat Treated Microstructure of IN-738 Superalloy

2020 ◽  
Vol 856 ◽  
pp. 36-42
Author(s):  
Chuleeporn Paa-Rai
Keyword(s):  
Heat Treatment ◽  
Image Analysis ◽  
Electron Microscope ◽  
Solution Treatment ◽  
Single Step ◽  
Double Step ◽  
Heat Treated ◽  
Cast Superalloy ◽  
Scanning Electron

This work investigates the effect of rejuvenation heat treatment, with double-step solution treatment at the temperature from 1150 °C to 1200 °C, on the recovered microstructure of IN-738 cast superalloy. The superalloy has been long-term exposed as a turbine blade in a gas turbine prior to this study. After double solution treatment and aging at 845 °C for 12 h and 24 h, the recovered microstructures were examined by using a scanning electron microscope. Coarse γ΄ particles, that have presented in damaged microstructures, could not be observed in the samples after the rejuvenation heat treatment. In addition, the image analysis illustrates that the reprecipitated γ΄ particles in the samples with double-step solution treatments increase significantly in sizes during aging than that in the samples with the single-step solution treatment. Furthermore, the measurement of the samples hardness presents that the as-receive sample hardness is improved after rejuvenation heat treatment studied in this work.

scholarly journals Tracking a mass mortality outbreak of pen shell Pinna nobilis populations: A collaborative effort of scientists and citizens

2019 ◽  
Vol 9 (1) ◽  
Author(s):  
Miguel Cabanellas-Reboredo ◽  
Maite Vázquez-Luis ◽  
Baptiste Mourre ◽  
Elvira Álvarez ◽  
Salud Deudero ◽  
...  
Keyword(s):  
Additive Model ◽  
Mass Mortality ◽  
Salinity Range ◽  
Pinna Nobilis ◽  
Mass Mortality Event ◽  
Virtual Particles ◽  
Management Measures ◽  
Pen Shell ◽  
The Mediterranean

Abstract A mass mortality event is devastating the populations of the endemic bivalve Pinna nobilis in the Mediterranean Sea from early autumn 2016. A newly described Haplosporidian endoparasite (Haplosporidium pinnae) is the most probable cause of this ecological catastrophe placing one of the largest bivalves of the world on the brink of extinction. As a pivotal step towards Pinna nobilis conservation, this contribution combines scientists and citizens’ data to address the fast- and vast-dispersion and prevalence outbreaks of the pathogen. Therefore, the potential role of currents on parasite expansion was addressed by means of drift simulations of virtual particles in a high-resolution regional currents model. A generalized additive model was implemented to test if environmental factors could modulate the infection of Pinna nobilis populations. The results strongly suggest that the parasite has probably dispersed regionally by surface currents, and that the disease expression seems to be closely related to temperatures above 13.5 °C and to a salinity range between 36.5–39.7 psu. The most likely spread of the disease along the Mediterranean basin associated with scattered survival spots and very few survivors (potentially resistant individuals), point to a challenging scenario for conservation of the emblematic Pinna nobilis, which will require fast and strategic management measures and should make use of the essential role citizen science projects can play.

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