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During an organism’s evolution, functional adaptations help species to become better suited to their ecological niches. From the morphological aspect, these adaptations are reflected in the anatomical specializations of different organs. Specializations of the lingual organ is a critical adaptation of birds, such as the white-headed duck (Oxyura leucocephala), that enables their nutritional requirements to be met. For optimal use of the available food resources, the white-headed duck utilizes three methods of food collection, namely pecking, grazing and filter-feeding. Since this species is classified as endangered, we conducted the present study on two carcasses of the white-headed duck (death due to natural causes) employing routine histological methods, light microscopy and scanning electron microscopy. Our results show that the tongue of this bird shares some similarities and some differences with the tongue of other members of the family Anatidae. The results confirm that it is better adapted to the filter-feeding method rather than to other types of food intake. This adaptation is reflected by anatomical specializations of its lingual structures, including the stair-like outline shape, bi-sectional lingual body, a deep median sulcus, lateral conical papillae, mucus secreting glands, lack of serous secreting glands, cartilaginous skeleton and the triangular fibromuscular structure of the lingual body. The so-called triangular structure and cartilaginous skeleton are the major structures involved in the lingual motions during the filter-feeding method. The presence of the triangular structure and its connection with the cartilaginous skeleton and lingual mucosa have not previously been reported in any species of birds. [ABSTRACT FROM AUTHOR]

This study was conducted to depict anatomical characteristics of the penis of he-dgehog. Seven sexually mature male European hedgehogs were used. Following anaesthesia, the animals were scarified with chloroform inhalation. Gross penile characteristics such as length and diameter were thoroughly explored and measu-red using digital callipers. Tissue samples stained with haematoxylin and eosin and Masson's trichrome for microscopic analysis. The penis of the European hedgehog was composed of a pair of corpus cavernosum penis and the glans penis without corpus spongiosum penis. The urethra at the end of penis, protruded as urethral process, on both sides of which two black nail-like structures, could be observed. The lower part was rounded forming a blind sac (sacculus urethralis) with a me-dian split below the urethra. Microscopically, the penile bulb lacked the corpus spongiosum penis, but, corpus spongiosum glans was seen at the beginning of the free part. In the European hedgehog, entirely stratified squamous epithelium of penile urethra, absence of corpus spongiosum penis around the urethra and bilateral urethral glands are basically different compared with other mammals. This information is expected to contribute to comparative penile morphology as well as for testing phylogenic hypotheses and expanding knowledge about reproductive biology in this animal. (Folia Morphol 2018; 77, 2: 293-300). [ABSTRACT FROM AUTHOR]

The hedgehog tongue is a tactile and taste organ which carries out various functions. Detailed functional and morphological studies are required to clearly define the relationship of the hedgehog tongue with taste, food palatability, mastication and swallowing of food, as well as the production of sounds. The aim of this study was to determine the relationship between the morphological characteristics of the European hedgehog tongue and the lifestyle of this animal, as well as to compare findings with the results of studies on other vertebrates. Gross and micro-anatomical light and scanning electron microscopy studies revealed that the hedgehog tongue could be divided in three areas, namely the apex, body and root. A keratinized stratified squamous epithelium, which was smooth on the ventral surface but bore four types of papillae on the dorsal surface, lined the tongue. Three types of these papillae were found to have gustatory functions and to express their activity in close relation with the salivary glands. These simple conical filiform papillae were situated caudally and distributed one after the other without a break. The dome-shaped fungiform papillae on the apex, with the highest distribution rate on the apex edge, were small, but those on the body and root were large. The three circular vallate papillae were arranged in a triangular shape. The foliate papillae with a few tiny projections, found in a shallow furrow, were situated between the root and the body. Most of the nerve fibers observed in different sections of the tongue tissue were of the unmyelinated type, confirming that the main task of the hedgehog tongue was its gustatory function. [ABSTRACT FROM AUTHOR]

In this study, flexible polyurethane (PU) nanocomposite foams were prepared by in situ polymerization. The effects of incorporation of nanoparticles on the morphological and structural developments and the relation between this development and mechanical properties of the PU foam were demonstrated. The effects of three different contents (low, moderate, and high) of nanoclay and multiwall carbon nanotubes (MWNTs) loading on foam morphology, structure, kinetics of foaming reactions, and mechanical properties were separately investigated. By adding MWNTs and nanoclay in foams, the foam morphology improved, in which cell density increased and smaller cells were obtained. The mechanical properties of foam especially tensile strength have been increased in the presence of nanoparticles. With enhancing the nanoclay content, the tensile strength of nanocomposite foam has improved but in the case of MWNTs contrary effects were observed. An increase in nanoparticle amount leads to a lower cell density. In general, the incorporation of both nanoparticles (nanoclay and MWNTs) in the foam structure leads to a lower foaming reaction rate that affects mechanical properties of foams. © 2012 Wiley Periodicals, Inc. Adv Polym Techn 32: E545-E555, 2013; View this article online at wileyonlinelibrary.com. DOI 10.1002/adv.21300 [ABSTRACT FROM AUTHOR]

The affiliation of the third author has been incorrectly published in the original publication of the article. The correct affiliation is provided in this erratum. [ABSTRACT FROM AUTHOR]