scholarly journals Notable seasonal variation observed in the morphology of the reindeer rumen fluke (Paramphistomum leydeni) in Finland

Rangifer ◽  
2009 ◽  
Vol 27 (1) ◽  
Author(s):  
Sven Nikander ◽  
Seppo Saari
Keyword(s):  
Genital Atrium ◽  
Immature Stage ◽  
Species Level ◽  
Surface Structures ◽  
Mature Stage ◽  
Internal Anatomy ◽  
Morphological Findings ◽  
Paramphistomum Leydeni ◽  
Paramphistomum Cervi ◽  
Scanning Electron

Although numerous Paramphistomum species have been described from the rumen and reticulum of domestic and wild ruminants, information about rumen flukes in reindeer is sparse and their nomenclature is somewhat conflicting. Rumen fluke of reindeer is usually referred to as P. cervi, but P. leydeni and Cotylophoron skriabini are also mentioned in the literature. Here, the surface structures and internal anatomy of rumen flukes from reindeer, as seen by scanning electron microscopy (SEM) and in histological sections under light microscopy, are presented. The aim of the study was to find morphological information to enable identification of rumen flukes in reindeer to species level. In addition, the morphology of rumen flukes collected in winter (winter flukes) was compared with that of flukes collected in summer (summer flukes). Key morphological findings were as follows: the acetabulum of the rumen flukes was of paramphistomum type, the pharynx of liorchis type, and the genital atrium of leydeni type. Both winter and summer flukes shared these morphological features. Based on these findings, it was concluded that rumen flukes of reindeer in Finland belonged to the species P. leydeni. Significant morphological variation was observed when winter and summer flukes were compared. The winter fluke was smaller in size, possessed immature gonads (testes, ovary, uterus), and immature accessory genital glands (Mehlis’ gland, vitelline follicles), and had barely discernible tegumental papillae. These data indicate that winter rumen flukes represent an immature stage of P. leydeni and summer flukes the mature stage of the same species. Further, these findings suggest that the rumen flukes of reindeer during wintertime in Finland have a slowed or inhibited lifecycle.Abstract in Finnish / Yhteenveto:Poron pötsimadon (Paramphistomum leydeni) morfologiassa esiintyy selvää vuodenaikaisvaihtelua Pötsimatoja (Paramphistomum spp.) löytyy monien villien ja kotieläiminä pidettävien märehtijöiden pötsistä tai verkkomahasta. Poron pötsimadosta on saatavilla varsin niukasti tietoa, ja lähteestä riippuen poron pötsimadon esitetään yleensä kuuluvan Paraphistomum cervi -lajiin. P. leydeni ja Cotylophoron skriabini ovat muita poron pötsimadon yhteydessä kirjallisuudessa esiintyviä lajinimiä. Tässä tutkimuksessa pyrittiin saamaan lisävalaistusta poron pötsimatojen taksonomiaan tunnistamalla Suomessa poroilta kerättyjä pötsimatoja lajitasolle. Tutkimuksessa käytettiin pötsimadoista tehtyjen kudosleikkeiden mikroskooppisen tutkimuksen sekä pyyhkäisyelektronimikroskoopin tarjoamia mahdollisuuksia. Lisäksi tutkimuksessa verrattiin poron pötsistä talviteurastuksen yhteydessä kerättyjen matojen rakennetta kesällä kuolleiden tai lopetettujen porojen pötsistä saatuihin matoihin. Sekä talvella että kesällä poimitut madot - huolimatta huomattavasta morfologisesta vaihtelusta ”talvi- ja kesämatojen” välillä - kuuluivat Paramphistomum leydeni -lajiin. Talvella kerätyt madot olivat selvästi pienikokoisempia, niiden ulkopinta oli vain niukasti nystyinen ja niiden sukuelimet apuelimineen olivat kehittymättömät verrattaessa niitä kesällä poimittujen matojen vastaaviin rakenteisiin. Tutkimuksen tulokset viittaavat siihen, että talvella poron pötsissä esiintyvät pienikokoiset pötsimadot ovat keskenkasvuisia P. leydeni -pötsimatoja ja että Suomessa pötsimadon kehittyminen on talvisaikaan pysähdyksissä tai hyvin hidasta. Abstract in Swedish / Sammandrag: Renens vomflundra (Paramphistomum leydeni) uppvisar en tydlig morfologisk årstidsvariation Vomflundror (Paramphistomum spp.) förekommer i vommen hos vilda och tama idisslare. Uppgifter om renens vomflundror är sparsamma och de presenteras i allmänhet som Paramphistomum cervi. P. leydeni och Cotylophoron skriabini är andra i litteraturen nämnda artnamn för renens vomflundror. I denna undersökning strävade man till att få information om renens vomflundrors taxonomi genom att identifiera vomflundror som insamlats från renar i Finland. I undersökningen studerades vävnadssnitt av vomflundror med ljusmikroskop och scanningelektronmikroskopets möjligheter utnyttjades också. Därtill gjordes en morfologisk jämförelse av vomflundror som insamlats under renslakten på vintern med vomflundror som härstammade från renar som dött eller avlivats under sommaren. Trots betydande morfologiska variationer mellan de vomflundror som insamlades på vintern och de som erhölls på sommaren var det fråga om en och samma art, Paramphistomum leydeni. ”Vinter” vomflundrorna var betydligt mindre, ytan var obetydligt knottrig och könsorganen med tillhörande strukturer var outvecklade i jämförelse med motsvarande strukturer hos ”sommar” vomflundrorna. Undersökningen ger en antydan om att de på vintern i renens vom förekommande små vomflundrorna är unga P. leydeni vomflundror och att de utvecklas mycket långsamt eller rentav tillfälligt avstannar i sin utveckling på vintern i Finland.

Scanning and Transmission Microscopy of Nematocyst Batteries in Epitheliomuscular Cells of Hydra

1971 ◽  
Vol 29 ◽  
pp. 410-411 ◽  
Author(s):  
Jane A. Westfall ◽  
S. Yamataka ◽  
Paul D. Enos
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Osmium Tetroxide ◽  
External Surface ◽  
Three Dimensional ◽  
Surface Structures ◽  
Transmission Microscopy ◽  
Transmission Electron ◽  
Freeze Dried ◽  
Scanning Electron

Scanning electron microscopy (SEM) provides three dimensional details of external surface structures and supplements ultrastructural information provided by transmission electron microscopy (TEM). Animals composed of watery jellylike tissues such as hydras and other coelenterates have not been considered suitable for SEM studies because of the difficulty in preserving such organisms in a normal state. This study demonstrates 1) the successful use of SEM on such tissue, and 2) the unique arrangement of batteries of nematocysts within large epitheliomuscular cells on tentacles of Hydra littoralis.Whole specimens of Hydra were prepared for SEM (Figs. 1 and 2) by the fix, freeze-dry, coat technique of Small and Màrszalek. The specimens were fixed in osmium tetroxide and mercuric chloride, freeze-dried in vacuo on a prechilled 1 Kg brass block, and coated with gold-palladium. Tissues for TEM (Figs. 3 and 4) were fixed in glutaraldehyde followed by osmium tetroxide. Scanning micrographs were taken on a Cambridge Stereoscan Mark II A microscope at 10 KV and transmission micrographs were taken on an RCA EMU 3G microscope (Fig. 3) or on a Hitachi HU 11B microscope (Fig. 4).

Electron Microscopic Observation of Biological Specimens in Their Native State by Employing Cryogenic Techniques

1972 ◽  
Vol 30 ◽  
pp. 410-411 ◽  
Author(s):  
Tokio Nei ◽  
Haruo Yotsumoto ◽  
Yoichi Hasegawa ◽  
Yuji Nagasawa
Keyword(s):  
Electron Microscopic Observation ◽  
Surface Structures ◽  
Specimen Preparation ◽  
Native State ◽  
Electron Microscopic ◽  
Biological Specimen ◽  
Specimen Holder ◽  
Cold Stage ◽  
Preparation Techniques ◽  
Scanning Electron

In order to observe biological specimens in their native state, that is, still containing their water content, various methods of specimen preparation have been used, the principal two of which are the chamber method and the freeze method.Using its recently developed cold stage for installation in the pre-evacuation chamber of a scanning electron microscope, we have succeeded in directly observing a biological specimen in its frozen state without the need for such conventional specimen preparation techniques as drying and metallic vacuum evaporation. (Echlin, too, has reported on the observation of surface structures using the same freeze method.)In the experiment referred to herein, a small sliced specimen was place in the specimen holder. After it was rapidly frozen by freon cooled with liquid nitrogen, it was inserted into the cold stage of the specimen chamber.

scholarly journals Characteristics of Reconstituted Collagen Fibers from Chicken Keel Cartilage Depends on Salt Type for Removal of Proteoglycans

Molecules ◽  
2021 ◽  
Vol 26 (12) ◽  
pp. 3538
Author(s):  
Anna Pudło ◽  
Szymon Juchniewicz ◽  
Wiesław Kopeć
Keyword(s):  
Electron Microscopy ◽  
Rheological Properties ◽  
Thermal Denaturation ◽  
Surface Structures ◽  
Scanning Calorimetry ◽  
Cartilage Extracellular Matrix ◽  
Oscillatory Rheometry ◽  
Freeze Dried ◽  
Basic Features ◽  
Scanning Electron

The aim of the presented research was to obtain reconstituted atelocollagen fibers after extraction from poultry cartilage using the pepsin-acidic method in order to remove telopeptides from the tropocollagen. Firstly, we examined the extraction of collagen from the cartilage extracellular matrix (ECM) after proteoglycans (PG) had been removed by the action of salts, i.e., NaCl or chaotropic MgCl2. Additionally, the effects of the salt type used for PG and hyaluronic acid removal on the properties of self-assembled fibers in solutions at pH 7.4 and freeze-dried matrices were investigated. The basic features of the obtained fibers were characterized, including thermal properties using scanning calorimetry, rheological properties using dynamic oscillatory rheometry, and the structure by scanning electron microscopy. The fibers obtained after PG removal with both analyzed types of salts had similar thermal denaturation characteristics. However, the fibers after PG removal with NaCl, in contrast to those obtained after MgCl2 treatment, showed different rheological properties during gelatinization and smaller diameter size. Moreover, the degree of fibrillogenesis of collagens after NaCl treatment was complete compared to that with MgCl2, which was only partial (70%). The structures of fibers after lyophilization were fundamentally different. The matrices obtained after NaCl pretreatment form regular scaffolds in contrast to the thin, surface structures of the cartilage matrix after proteoglycans removal using MgCl2.

scholarly journals Лазерно-индуцированные пространственно-периодические структуры на поверхности титана в среде н-гексана при различном давлении

2020 ◽  
Vol 46 (15) ◽  
pp. 51
Author(s):  
Д.А. Кочуев ◽  
К.С. Хорьков ◽  
А.С. Черников ◽  
Р.В. Чкалов ◽  
В.Г. Прокошев
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Laser Radiation ◽  
Pressure Range ◽  
Titanium Surface ◽  
Surface Structures ◽  
Femtosecond Laser Radiation ◽  
Periodic Surface ◽  
Laser Induced Plasma ◽  
Scanning Electron

The paper presents the results of processing titanium surface in n-hexane at various pressures by femtosecond laser radiation. The effect of laser-induced plasma on the nature of the formation of periodic surface structures in the pressure range from 6 mbar to 22 bar is considered. The study of the surface of the processed samples was carried out using scanning electron microscopy. The dependence of the period of obtained laser-induced periodic surface structures on the pressure in working vessel and the treatment regime is shown.

Effect of Functionalized MWCNT on the Mechanical and Dielectric Properties of PMMA Nanocomposites

2018 ◽  
Vol 18 (06) ◽  
pp. 1850035
Author(s):  
Punyapriya Mishra ◽  
Narasingh Deep ◽  
Sagarika Pradhan ◽  
Vikram G. Kamble
Keyword(s):  
Mechanical Properties ◽  
Carbon Nanotubes ◽  
Dielectric Constant ◽  
Tensile Strength ◽  
Electron Microscope ◽  
Dielectric Properties ◽  
Conductive Polymer ◽  
Mechanical Tests ◽  
Surface Structures ◽  
Scanning Electron

Carbon nanotubes (CNTs) are widely explained in fundamental blocks of nanotechnology. These CNTs exhibit much greater tensile strength than steel, even almost similar to copper, but they have higher ability to carry much higher currents, they seem to be a magical material with all these mentioned properties. In this paper, an attempt has been made to incorporate this wonder material, CNT, (with varying percentages) in polymeric matrix (Poly methyl methacrylate (PMMA)) to create a new conductive polymer composite. Various mechanical tests were carried out to evaluate its mechanical properties. The dielectric properties such as dielectric loss and dielectric constant were evaluated with the reference of temperature and frequency. The surface structures were analyzed by Scanning Electron Microscope (SEM).

scholarly journals Seed morphology and histology of some Paronychia taxa (Caryophyllaceae) from Turkey

1970 ◽  
Vol 38 (2) ◽  
pp. 171-176 ◽  
Author(s):  
Ayse Kaplan ◽  
Hatice Çölgeçen ◽  
H Nurhan Büyükkartal
Keyword(s):  
Key Words ◽  
Seed Morphology ◽  
Epidermal Cells ◽  
Surface Structures ◽  
Dichotomous Key ◽  
Electron Microscopes ◽  
Scanning Electron Microscopes ◽  
Scanning Electron

Seed morphology and histology of 12 taxa (nine species, two subspecies, one variety) of Paronychia Miller (Caryophyllaceae) by light and scanning electron microscopes revealed that seeds are laterally compressed, reniform, and hilums are linear. Testa surface structures are alveolate-scalariform, colliculate, reticulate-alveolate, rugose and ruminate. Differences in cuticle and papillae properties of epidermal cells have been observed. A dichotomous key has been developed for Paronychia agryloba Stapf, P. angorensis Chaudri, P. arabica (L.) DC. subsp. euphratica Chaudri, P. carica Chaudri, P. cataonica Chaudri, P. condensata Chaudri, P. davisii Chaudri, P. dudleyi Chaudri, P. galatica Chaudri, P. kurdica Boiss subsp. kurdica var. kurdica, P. kurdica Boiss subsp. montis-munzur Chaudri and P. mughlaei Chaudri.   Key words: Paronychia; Caryophyllaceae; Seed morphology; Seed histology; Turkey DOI: 10.3329/bjb.v38i2.5142 Bangladesh J. Bot. 38(2): 171-176, 2009 (December)  

scholarly journals SEM Investigation of Pollen Taxa in Honeys from Autochtone Apis cerana in Godavari, Lalitpur District, Nepal

2015 ◽  
Vol 26 ◽  
pp. 29-67 ◽  
Author(s):  
Khum Narayan Paudayal ◽  
Ishan Gautam
Keyword(s):  
Honey Bees ◽  
Apis Cerana ◽  
Pollen Grains ◽  
Species Level ◽  
Palynological Assemblage ◽  
Wide Range ◽  
Multifloral Honey ◽  
Plant Sources ◽  
Sem Investigation ◽  
Scanning Electron

Pollen analysis of 8 multifloral honey samples collected from 4 locations of Godavari, Lalitpur district, Nepal was performed using Scanning Electron Microscope (SEM). In this investigation, a wide range of foraging plant sources for Apis cerana honey bees was identified which demonstrates the adequate potential for expanding and sustaining beekeeping in this area. The palynological assemblage of a total of 44 species of pollen flora representing 28 families was identified to the generic and some up to species level. Some of the pollen grains identified to only families, belong to Acanthaceae, Apiaceae, Araliaceae, Chenopodiaceae, Compositae, Lamiaceae, Loranthaceae, Meliaceae, Poaceae, Rosaceae, Rutaceae and Pteridaceae. The pollen assemblages in honeys were mostly belonging to angiosperms while the gymnosperm pollen was completely absent. One pteridophyte spore belonging to family Pteridaceae recovered. In this paper the morphology of the pollen grains based on SEM observation are described and the importance of the systematic documentation of various bee flora are discussed.J. Nat. Hist. Mus. Vol. 26, 2012: 29-67

Taxonomically Important Features on the Surface of Floatoblasts in Plumatella (Bryozoa)

2000 ◽  
Vol 6 (3) ◽  
pp. 202-210
Author(s):  
Kevin T. Reynolds
Keyword(s):  
Electron Microscopy ◽  
United States ◽  
Scanning Electron Microscopy ◽  
Suture Line ◽  
Species Level ◽  
Surface Features ◽  
The Family ◽  
Group A ◽  
Distinguishing Features ◽  
Scanning Electron

Abstract At the species level, bryozoans (class Phylactolaemata) in the family Plumatellidae are difficult to organize taxonomically. Of principal concern is the absence of consistent distinguishing features due mainly to plasticity of the group, a common problem with soft-bodied invertebrates. Yet, within the last three decades, analysis of distinctive chitinous statoblasts—using scanning electron microscopy—has resolved certain taxonomic questions. I examined statoblasts from 30 similar collections, the majority from the midwestern United States, and identified four distinct subgroups. Also, nine new statoblast surface features were identified: fold, polar grooves, bead, cave, demarcation, parasutural zone, ridge, sutural band, and sutural knob. The surface features of floating statoblasts (floatoblasts) provide useful data for species identification. Most consistently useful in plumatellids is a suture which varies from one species to the next. Mound-like tubercles and net-like ridges are next in the extent of variability. Finally, folds and polar grooves are present but vary even within floatoblasts from the same colony. Analysis of the suture in Plumatella fungosa, over a 5-day germination period, reveals all features at the site remain intact regardless of the initial age of the floatoblast. Only the suture line itself splits lengthwise to permit emergence of the new animal.

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