Bare Parts Research Articles

Considering play: From method to analysis

This paper deals with play as an important methodological issue when studying games as texts, and is intended as a practical methodological guide. After considering text as both the structuring object as well as its plural processual activations, we argue that different methodological considerations can turn the focus towards one of the two (without completely excluding the other). After outlining and synthesizing a broad range of existing research we move beyond the more general advice to be reflective about the type of players that we are, and explore two methodological considerations more concretely. First of all, we discuss the various considerations to have regarding the different choices to make when playing a game. Here we show how different instrumental and free strategies lay bare different parts of the game as object and/or process. Secondly, we consider how different contexts in which the game and the player exist, can function as different reference points for meaning construction and the way they can put limitations on the claims we can make about our object of analysis.

First record of colour aberration in Basra Reed Warbler Acrocephalus griseldis (Hartlaub, 1891) (Passeriformes: Acrocephalidae) from Central Marshes of southern Iraq, with notes on its intraspecific/interspecific behavior

Pigment disorders such as albinism, leucism and progressive greying, which cause the absence of melanin pigments in all or parts of the plumage and bare parts, have been reported in many wild bird populations including Acrocephalus warblers. Basra Reed Warbler Acrocephalus griseldis (Hartlaub, 1891) is a restricted-range species confined to the extensive reed beds of Mesopotamian marshes. It is listed as Endangered due to breeding habitat degradation, water scarcity and climate change. In April 2018, a partly white plumaged Basra Reed Warbler was sighted in Central Marshes in southern Iraq. This is the first report of such a plumage aberration in this species. The nature of the aberration involved an intraspecific/interspecific behavior of the white plumaged Basra Reed Warbler are described.

Botanical composition, forage yield and quality under different improved Mediterranean rangeland

Proliferation of invasive of annual plant species and thorny shrubs such as Christ’s thorn (Paliurus spina-christi) is common in Mediterranean rangelands due to climatic shifts and heavy grazing. Improved practices are needed to manage such invasive species. This study assessed how improved rangeland practices affected herbage yield and quality, botanical composition in the Canakkale in western Turkey. The rangeland practices were: 1. control (no improvement practices (C), 2. removal of Christ’s thorns followed by forage crop planting (R), 3. use of herbicides to treat Christ’s thorn shrubs (H), 4. removal of Christ’s thorn shrubs by grubbing with dozers and rippers (M), and 5. the shrubs were cut out in the rangelands dominated with Christ’s thorn. The field has been plowed deep by a tractor. Then, it had been used as field for 10 years (sown with wheat). At the end, it has been turned back in the form of rangelands by sowing forage crops (F). The seeding practice has been done into bare parts of the rangelands that were occurred due to the removal of Christ’s thorn. The treatment plots were seeded with perennial ryegrass, orchardgrass and alfalfa. Control had the greatest number of species (45 species) whereas mechanically-treated plot had the least (28 species). All treatments increased herbage yield and grazed herbage quantities of the rangelands. The mechanically-treated rangeland increased yield by 2.5 folds compared with control. Treatments did not affect herbage quality of the rangelands. Results indicate that improvement practices improved rangelands invaded with Christ’s thorn shrubs.

Repeatability of a dynamic sexual trait: Skin color variation in the Brown Booby (Sula leucogaster)

ABSTRACT Individual capacity to invest in a reproductive attempt may change over the breeding season, and such changes may be evaluated by potential partners through signaling mechanisms. Coloration of bare parts, such as exposed skin on the throat (gular skin) or feet, is common among avian species and has the potential to be a dynamic, honest signal of current condition, especially when such coloration is carotenoid-dependent. However, few studies have evaluated the repeatability of dynamic coloration of bare parts in the wild. We determined the presence of carotenoid pigments (lutein, zeaxanthin, 13-cis-beta-carotene, and trans-gamma-carotene) in gular skin samples of male and female Brown Boobies (Sula leucogaster) using high performance liquid chromatography (HPLC). We then studied color and perceived color variation in the gular skin of both sexes over the reproductive season, from courtship through parental care. We estimated color using Endler's segment method and perceived color using a tetrahedr...

Plumage brightness and uropygial gland secretions in barn swallows.

The uropygial gland has been hypothesized to play a role in sexual signaling through a “make-up” function derived from the effects of secretions from the gland on the appearance of the plumage and bare parts of the body. Here we show that plumage brightness of dorsal feathers of individual barn swallows Hirundo rustica was greater in mated than in unmated individuals. In addition, plumage brightness increased with colony size. Furthermore, plumage brightness was positively correlated with the amount of wax in the uropygial gland, negatively correlated with time of sampling of uropygial wax (perhaps because more wax is present early in the morning after an entire night of wax production without any preening), and negatively correlated with the number of chewing lice that degrade the plumage. Experimentally preventing barn swallows from access to the uropygial gland reduced plumage brightness, showing a causal link between secretions from the uropygial gland and plumage brightness. These findings provide evidence consistent with a role of uropygial secretions in signaling plumage brightness.

Dietary canthaxanthin reduces xanthophyll uptake and red coloration in adult red-legged partridges.

Carotenoids give color to conspicuous animal signals that are often the product of sexual selection. Knowledge of the mechanisms involved in carotenoid-based signaling is critical to understanding how these traits evolve. However, these mechanisms remain only partially understood. Carotenoids are usually viewed as scarce dietary antioxidants whose allocation to ornaments may trade off against health. This trade-off would ensure its reliability as a signal of individual quality. In the case of red (keto)carotenoids, the literature suggests that some species may show constraints in their uptake. Canthaxanthin is one of the most common ketocarotenoids in red ornaments of animals. It is often commercially used as a dietary supplement to obtain redder birds (e.g. poultry). We increased the dietary canthaxanthin levels in captive red-legged partridges (Alectoris rufa). This species shows red non-feathered parts mostly pigmented by another common ketocarotenoid: astaxanthin. We studied the impact on the uptake of carotenoids and vitamins and, finally, on coloration. We also tested the potential protective effect of canthaxanthin when exposing birds to a free radical generator (diquat). Canthaxanthin did not apparently protect birds from oxidative stress, but interfered with the absorption of yellow carotenoids (lutein and zeaxanthin). Zeaxanthin is a precursor of astaxanthin in enzymatic pathways, and their levels in tissues and eggs were lower in canthaxanthin-supplied birds. This led to lower astaxanthin levels in ornaments and paler coloration. As far as we know, this is the first report of a carotenoid supplementation decreasing animal coloration. The results have implications for understanding carotenoid-based signaling evolution, but also for improving husbandry/experimental procedures.

The role of bare parts in avian signaling

ABSTRACT Avian plumage has captivated scientists and the public alike for generations and has been a fundamental study system for research into signal evolution. By contrast, relatively little attention has been paid to avian bare parts such as exposed skin, bills, feet, and combs, despite considerable variation in structure and coloration within and between species. To better understand the potential signaling role of bare parts, we conducted a comprehensive literature search that returned 321 published studies. In reviewing these studies, we found that (1) bare-part color is widely distributed taxonomically and is produced by diverse mechanisms; (2) many bare parts are likely to be dynamic, honest signals of current condition or status and can also reflect genetic makeup and early developmental conditions; and (3) bare parts can function as pluripotent social signals, mediating interactions between competitors, mates, and kin. Differences between bare parts and plumage in phenology and information conte...

Developing a new individualized 3-node model for evaluating the effects of personal factors on thermal sensation

Individual differences, such as weight, height, gender, age, and Basal Metabolic Rate (BMR), between human subjects can significantly affect body thermoregulatory mechanisms. Therefore, application of common population-based thermal comfort models cannot provide accurate results for an individual's thermal sensation. Based on the standard thermal models, including those of Fanger and Gagge, individual parameters are not considered in the evaluation of thermal sensations. Thus, these simplified standard models have some limitations under varied individual conditions. In this study, a new individualized thermal comfort model is presented on the basis of a simplified 3-node model. This model was developed by regarding the effects of individual characteristics, such as age, gender, Body Mass Index (BMI), and BMR on the thermal sensations of the bare and clothed parts of the body. A good agreement was found in the current model, which was verified based on the experimental data. In conclusion, the results indicated that the mean error in the prediction of skin temperature decreased from 1.2°C to 0.4°C when using the new individual model instead of a non-individualized 3-node model.

Bill colour pattern in Bewick’s swan: information on sex and body size displayed on face?

Ornamental traits in birds (plumage/bare part colours) have been shown to provide information on diverse aspects of individual quality and behaviour. In bird species with achromatic plumages (uniformly white, grey or black), signals encoded in bare parts are the major mode of visual communication. In this study we analysed the influence of sex, age, body condition and selected biometric traits on the bill colour pattern in Bewick’s swans Cygnus columbianus bewickii. The results indicate that sex and body size (weight and tarsus length) are associated with the bill colour pattern in Bewick’s swans. Individuals with a larger black area on the bill were heavier and had a longer tarsus. Moreover, females had more black on their bills than males did. Age, head length and body condition index were not significantly related to bill colour pattern. The present work indicates that Bewick’s swans may display information on their sex and size by means of their bill colour pattern. These findings also suggest the possibility that swans can remotely quantify one another’s traits from the appearance of their bill colouration. Proper assessment of an opponent or of mate quality during face-to-face signalling may help birds to avoid unnecessary interaction or to maintain bonds between mates and family groups.

A bare-part ornament is a stronger predictor of dominance than plumage ornamentation in the cooperatively breeding Australian Swamphen

ABSTRACT Many animals use coloration to signal dominance and fighting ability. In birds, plumage coloration is often linked to individual quality, but less research has investigated coloration in unfeathered traits (i.e. ‘bare parts'), despite theoretical expectations that they might be more reliable signals. Here, we investigate the relationship between multiple ornaments and social dominance in a wild population of the cooperatively breeding Australian Swamphen (known locally as and hereafter referred to as Pūkeko; Porphyrio melanotus melanotus) to test the hypothesis that bare-part ornaments should be more strongly correlated with dominance than plumage coloration. We show that the size and color of the pūkeko's frontal shield (a bare-part ornament), as well as the brightness and chroma of the blue-UV breast plumage, are correlated with social dominance in adult birds. However, the correlation between frontal shield size and dominance was much higher than that between plumage color and dominance, and w...

Aromatic thermosetting copolyester foam core and aluminum foam face three-layer sandwich composite for impact energy absorption

In this work, we introduce a three-layer sandwich composite structure having an aromatic thermosetting copolyester (ATSP) foam core with two aluminum foam face layers joined together by an in situ generated foaming mechanism. The ATSP foam core was synthesized on-site between the aluminum foam layers via a heat-induced polycondensation reaction. Upon curing, the ATSP foam core adhered to the aluminum foam layers through an interfacial compatibility-enabled chemical bonding. Lap shear experiments demonstrated that the bond strength clearly surpassed the tensile performance of the bare aluminum foam parts. Drop-weight impact tests showed that the three-layer sandwich structure could absorb four times the impact energy as compared to the bare aluminum foam of the same overall thickness.

Acquired atresia and stenosis of the external acoustic meatus

Acquired atresia of the external acoustic meatus is a rare pathological condition characterized by obliteration of the medial part of the external acoustic canal by a soft fibrous plug. The present article presents an overview of a series of cases of acquired atresia and stenosis of the external acoustic meatus with the description of etiology, pathogenesis, and methods for the treatment of this condition. In the majority of the cases, atresia develops at the final stage of granulation external otitis with or without an accompanying dermatological pathology. Another common cause of the acquired atresia of the external acoustic meatus is the fracture of the temporal bone as well as extensive ear surgery, radiation therapy and a neoplasm in the auditory passage. The surgical strategy for the management of the acquired atresia and stenosis of the external acoustic meatus consists, besides the excision of the fibrous plug, of the application of the cutaneous flaps and/or transplants to cover the bare parts of the bone portion of the affected external canal. In spite of such treatment, the state of the external acoustic canal remains unstable, and a relapse of its atresia and stenosis can not be wholly excluded.

Bird Integumentary Melanins: Biosynthesis, Forms, Function and Evolution.

Melanins are the ubiquitous pigments distributed in nature. They are one of the main pigments responsible for colors in living cells. Birds are among the most diverse animals regarding melanin-based coloration, especially in the plumage, although they also pigment bare parts of the integument. This review is devoted to the main characteristics of bird melanins, including updated views of the formation and nature of melanin granules, whose interest has been raised in the last years for inferring the color of extinct birds and non-avian theropod dinosaurs using resistant fossil feathers. The molecular structure of the two main types of melanin, eumelanin and pheomelanin, and the environmental and genetic factors that regulate avian melanogenesis are also presented, establishing the main relationship between them. Finally, the special functions of melanin in bird feathers are also discussed, emphasizing the aspects more closely related to these animals, such as honest signaling, and the factors that may drive the evolution of pheomelanin and pheomelanin-based color traits, an issue for which birds have been pioneer study models.

Aberrant Colouration in the Atlantic Puffin (<i>Fratercula arctica</i>), the Common Murre (<i>Uria aalge</i>), and the Thick-billed Murre (<i>U. lomvia</i>) from Atlantic Canada

The colour of birds’ plumage and bare parts is an important feature in choice of mate, camouflage, thermoregulation, species recognition, and flight mechanics. Abnormalities in colouration occur in a variety of species and can have important consequences for an individual’s survival and fitness. We present 7 new cases of colouration abnormalities in 3 species of auk (Alcidae) and review previous reports to correctly assign the proper form of abnormality to specimens in museums or photographs. Of the 53 reported colouration abnormalities, we reclassified 42, progressive greying being the most common (18 or 19 cases out of 42, 43–45%), followed by brown (10/42 cases, 24%), in addition to 6 cases of melanism, 4 of dilution, 2 of partial leucism, and 1 likely somatic mutation. Properly describing the form of colour abnormality improves our understanding of the frequency, causes, and consequences of aberrant colouration.

Adsorption and Self-Assembly of Anticancer Antibiotic Doxorubicin on Single-Walled Carbon Nanotubes

We performed a combined experimental and theoretical study of the conjugates obtained from single-walled carbon nanotubes and anticancer antibiotic doxorubicin (DOX). Atomic force microscopy (AFM) imaging at lower magnification revealed, extended regions of single-walled carbon nanotubes (SWNTS) fully covered with DOX adsorbed molecules, along with some bare parts without the adsorbed drug, thus suggesting that the DOX adsorption is a cooperative process. Ambient atmosphere scanning tunneling microscopy (STM) at higher resolutions found that individual SWNTs-DOX conjugates exhibit a periodic texture, whose most important morphological feature is alternating depressions and protrusions along the nanotube. Based on the images and profiles measured, we suggest that doxorubicin molecules self-assemble on SWNTs sidewall according to a helical pattern, in which their tetracyclic fragments are turned with respect to the nanotube axis by about 50[Formula: see text]. To provide an additional insight into the structure of noncovalent SWNTs-DOX conjugates, we employed density functional theory (DFT) calculations with three long-range corrected functionals: M05-2X, wB97X-D and LCBLYP, of which M05-2X yielded the most realistic results in terms of geometries and energies.

Age and sex determination of Mallards Anas platyrhynchos in autumn

Male and female mallards Anas platyrhynchos are easily told apart, whereas ageing is problematic, due to individual timing of moult and lack of easily defined age criteria. From examination and photographic documentation of mallards caught at Ottenby Bird Observatory (56°12′N, 16°24′E), we describe nine characters of plumage and bare parts to be used for ageing in autumn. The reliability of these characters was tested by letting experienced bird ringers determine putative age of birds from photos. Age determination from any single character proved to be uncertain, as correctly assigned mallard photos of each character was in the range of 51–85% for males and 48–89% for females. For both sexes, the lowest figure represented post-humerals and the highest represented tertials. Rectrices, tertial coverts, and greater coverts had high scores (71–85%). Using all characters, 91% of the males and 95% of the females were correctly aged. As young mallards, with the progress of pre-breeding moult (completed from October onwards), acquire tail and tertials identical to adults, untypical individuals are better not assigned to an age category.

Body Size and Sexual Dimorphism in the Southernmost Subspecies of the Burrowing Owl (Athene cunicularia cunicularia)

Abstract We studied body size and sexual dimorphism in the southernmost subspecies of the Burrowing Owl (Athene cunicularia cunicularia) at the Pampas of Argentina, and we compared our data with those from other subspecies in the Americas. A total of 58 individuals were captured and their coloration pattern (plumage and bare parts), body linear measurements (wing chord, standard tail length, tarsus length and width, forearm length, exposed culmen length, and hallux claw length), and body mass were recorded. In addition, we banded each individual and took a blood sample from 44 individuals for molecular sex determination. In general, the body size measurements reported for A. c. cunicularia in this study agreed with previous reports based on museum specimens for the same subspecies, and were near the upper range for the species. In addition, tarsi of A. c. cunicularia were large in comparison to those of other subspecies. Sexes differed little in size, with tarsus length, tail length, and wing chord being ...

Carotenoid-based bill coloration functions as a social, not sexual, signal in songbirds (Aves: Passeriformes).

Many animals use coloration to communicate with other individuals. Although the signalling role of avian plumage colour is relatively well studied, there has been much less research on coloration in avian bare parts. However, bare parts could be highly informative signals as they can show rapid changes in coloration. We measured bill colour (a ubiquitous bare part) in over 1600 passerine species and tested whether interspecific variation in carotenoid-based coloration is consistent with signalling to potential mates or signalling to potential rivals in a competitive context. Our results suggest that carotenoid bill coloration primarily evolved as a signal of dominance, as this type of coloration is more common in species that live in social groups in the nonbreeding season, and species that nest in colonies; two socio-ecological conditions that promote frequent agonistic interactions with numerous and/or unfamiliar individuals. Additionally, our study suggests that carotenoid bill coloration is independent of the intensity of past sexual selection, as it is not related to either sexual dichromatism or sexual size dimorphism. These results pose a significant challenge to the conventional view that carotenoid-based avian coloration has evolved as a developmentally costly, condition-dependent sexual signal. We also suggest that bare part ornamentation may often signal different information than plumage ornaments.

Accumulation of dietary carotenoids, retinoids and tocopherol in the internal tissues of a bird: a hypothesis for the cost of producing colored ornaments.

Carotenoid-based ornaments may have evolved as a consequence of their costs of production, which would assure the reliability of the traits as signals of individual quality. Different costs due to carotenoid allocation to the signal have been proposed, considering the scarcity of these pigments at the environment (ecological cost) and their physiological properties that would trade against the maintenance of the organism. Carotenoids of many red ornaments (ketocarotenoids) are often the result of biotransformation of those pigments abundant in the diet (usually lutein and zeaxanthin). Some authors have suggested that such a conversion implies a cost relevant for signaling because it requires high levels of antioxidant vitamins in the tissues where biotransformation takes place. We explore this hypothesis in red-legged partridges (Alectoris rufa) by analyzing ketocarotenoids in the ornaments (bare parts) and carotenoids, vitamin A in different forms (free and esterified) and vitamin E in blood, liver and fat. Ketocarotenoids in ornaments (astaxanthin and papilioerythrinone) were not found in internal tissues, suggesting that they were directly transformed in the bare parts. However, ketocarotenoid levels where positively correlated with the levels of their precursors (zeaxanthin and lutein, respectively) in internal tissues. Interestingly, ketocarotenoid levels in bare parts negatively and positively correlated with vitamin A and E in the liver, respectively, the same links only being positive in blood. Moreover, retinyl and zeaxanthin levels in liver were negatively related. We hypothesize that storing substrate carotenoids in the main storage site (the liver) implies a cost in terms of regulating the level of vitamin A.

Progress in the Manufacturing of Molded Interconnected Devices by 3D Microcontact Printing

The aim of this paper is to report on the use of Microcontact Printing (μCP) for the manufacturing of 3D Molded Interconnects Devices. Two different approaches are reported. A first one is based on the total metallization of the polymer, μCP of the 3D pattern followed by the wet etching of the non-protected areas of the part (the so-called indirect process). A second approach is based on the combination of radio-frequency (RF) plasma treatment, μCP of a pattern of catalysts on the polymer and metallization by electroless deposition (the so-called direct process). This second process allows metallization of bare polymer parts (free of catalytic species in the bulk) with conductive 3D networks ready for the assembly of SMD devices. Examples of MID devices made with both approaches are reported. Key points like thickness (up to 12-15 μm), conductivity and adhesion of the metallic network are also reviewed. Printing on slope surfaces is demonstrated. Advantages and drawbacks of both processes are discussed.