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The common pauraque Nyctidromus albicollis (Gmelin, 1789) is a widespread avian species; however due to its nocturnal habits and reclusive behaviour, little is known about their vision and ecology. Most avian species are visually dependent with advanced visual systems providing high spatial resolution, on the species needs. Each ocular structure has a specific role in contributing towards high visual function, and the cornea is the first refractive structure in the visual process. However, the common pauraque cornea had not been described until the present data. Therefore, this study aims to describe the morphology and morphometry of the common pauraque cornea by means of light and scanning electron microscopy to evaluate the cross‐sectional anatomy as well as the ultrastructure of the endothelial cells. Histological similarities with the cornea of other birds have been observed, but the thickness of the common pauraque cornea is much smaller than the other described corneas. A better understanding of the common pauraque cornea can help us better explain the physiology of vision and the visual requirements of this species. In turn, this will help us better understand how this species successfully interacts with its environment, and will improve our knowledge on how to interpret pathological changes in their cornea in a clinical setting. [ABSTRACT FROM AUTHOR]

The article describes the problem of excessive traffic concentration at signalized pedestrian crossings. The main drawback of such crossings is the inappropriate duration of green signals for vehicles. Too long green times for vehicular traffic significantly increase time lost by pedestrians, while too short ones cause short-term congestion, resulting in long queues of vehicles and a deteriorated level of service. The negative effects of both of these situations also include dangerous behavior of road users, such as red light running or crossing. Recent (June 2021) changes in the road traffic law in Poland have privileged unprotected road users at pedestrian crossings. New models and technical and design standards proposed in this country (March 2021) recommend the installation of pedestrian priority crossings at particularly dangerous spots and in urban areas with a high proportion of pedestrian traffic. All this is done mainly for traffic-calming purposes. However, previously these measures were not a common practice in Poland. Therefore, the objective of this article was to develop a simple method of green signal timing, ensuring, firstly, priority to pedestrian traffic at such places, and, secondly, sustained capacity of vehicular traffic lanes. The developed models are practical, universal and easy to adapt in other countries. They ensure a very good or good quality of vehicle traffic service, with average lost time not exceeding 25 s in a vast majority of analyzed traffic level cases. The article also describes a traffic control algorithm dependent on traffic detection. [ABSTRACT FROM AUTHOR]

Charcoal‐rich Technosols on century‐old relict charcoal hearths (RCHs) are the subject of ongoing research regarding potential legacy effects that result from historic charcoal production and subsequent charcoal amendments on forest soil properties and forest ecosystems today. RCHs consist mostly of Auh horizons that are substantially enriched in soil organic carbon (SOC), of which the largest part seems to be of pyrogenic origin (PyC). However, the reported range of SOC and PyC contents in RCH soil also suggests that they are enriched in nonpyrogenic SOC. RCH soils are discussed as potential benchmarks for the long‐term influence of biochar amendment and the post‐wildfire influences on soil properties. In this study, we utilised a large soil sample dataset (n = 1245) from 52 RCH sites in north‐western Connecticut, USA, to quantify SOC contents by total element analysis. The contents of condensed highly aromatic carbon as a proxy for black carbon (BC) were predicted by using a modified benzene polycarboxylated acid (BPCA) marker method in combination with diffuse reflectance infrared Fourier transform (DRIFT) spectroscopy‐based partial least square regression (r2 = 0.89). A high vertical spatial sampling resolution allowed the identification of soil organic matter (SOM) enrichment and translocation processes. The results show an average 75% and 1862% increase in TOC and BPCA‐derived carbon, respectively, for technogenic Auh horizons compared to reference soils. In addition to an increase in aromatic properties, increased carboxylic properties of the RCH SOC suggest self‐humification effects of degrading charcoal and thereby the continuing formation of leachable aromatic carbon compounds, which could have effects on pedogenic processes in buried soils. Indeed, we show BPCA‐derived carbon concentrations in intermediate technogenic Cu horizons and buried top/subsoils that suggest vertical translocation of highly aromatic carbon originating in RCH Auh horizons. Topmost Auh horizons showed a gradual decrease in total organic carbon (TOC) contents with increasing depth, suggesting accumulation of recent, non‐pyrogenic SOM. Lower aliphatic absorptions in RCH soil spectra suggest different SOM turnover dynamics compared to reference soils. Furthermore, studied RCH soils featured additional TOC enrichment, which cannot be fully explained now. Highlights: BC to TOC ratio and high resolution vertical SOC distribution in 52 RCH sites were studied.RCH soils non‐BC pool was potentially different to reference soils.RCH soils feature TOC accumulation in the topmost horizon.There is BC translocation into buried soils on RCH sites. [ABSTRACT FROM AUTHOR]

The identification and characterization of hearths is crucial for reconstructing the history of fire use and pyrotechnology. In addition to ashes and charcoals, an active fire will also produce alterations of the underlying substrate to varying degrees. To date, however, few studies have addressed how the characteristics of burned substrates relate to pyrotechnology. Here, we systematize the use of colour to identify burnt sediments by performing quantitative colour measurements in the CIELab system of experimentally heated soils and sediments. The experimental design included different temperatures, different heating durations and substrates with varied chemical and mineralogical compositions, including naturally red soils and sediments with different degrees of pedogenesis. The measured colours were analysed by multivariate statistics for diagnosing whether sediments have been heated or not, and to which temperature. We achieved an accurate identification of heated versus unheated samples independently of their composition. The determination of the temperature of heating required prior knowledge of basic mineralogy and chemical properties in the targeted sediments (silicate or carbonate material, total and secondary Fe, Ca contents and the amount and kind of organic matter). The algorithm developed can be applied to recognize burned layers and estimate burning temperatures in archaeological contexts. [ABSTRACT FROM AUTHOR]

Background: Anophthalmia refers to the complete absence of an eyeball. It is a very rare congenital condition that affects all breeds of dogs, which may be unilateral or bilateral. Anophthalmia results from a severe developmental deficiency in the primitive forebrain, prior to the formation of the optic sulcus. This condition has a complex etiology, and chromosomal, monogenic, and environmental causes have already been identified. There might be an association between anophthalmia and other congenital abnormalities. This case report aimed to report the case of a male dog with bilateral anophthalmia associated with penile malformation. Case: A 3-year-old male mongrel dog was evaluated in a clinical consultation at the Veterinary Medical Teaching Hospital of the Federal University of Piauí (UFPI) - Teresina - Brazil, with signs of anemia and diarrhea. His vaccinations were not up to date (multiple and anti-rabies), presented ectoparasites (ticks), and showed inappetence. The owner reported that the animal was blind from birth, was already well adapted to its environment, had the company of other animals, and had no access to the street. On clinical examination, the animal had a good body score. The eyelids were bilaterally present with normally developed eyelashes. Both the head and face had a symmetrical appearance, without structural abnormalities, and the palpebral fissures were narrow. When opening the eyelids manually, the presence of the conjunctiva was observed bilaterally, the orbits were shallow, and neither orbit contained the eyeball. Further inspection with an ophthalmic clinical flashlight did not reveal any other ocular structures. The initial diagnosis was suggestive of bilateral anophthalmia. Ultrasound examination of the ocular region confirmed the presence of bilateral anophthalmia. A general physical examination revealed a malformed penis with a persistent penile frenulum. Regarding systemic clinical signs (apathy, inappetence, diarrhea, and anemia), clinical and laboratory examinations led to the suspicion of verminosis. Discussion: The dog in this report had a good body score; however, this type of malformation can generate non-viable puppies. Anophthalmia is an extremely rare congenital ocular malformation, both in humans and companion animals, in which there are no ocular structures in the orbits, and these structures (orbits) in affected individuals are generally small and shallow, as seen in the dog in this report. Ultrasonographic examination confirmed the bilateral anophthalmic condition, being the most accurate method of diagnosing this congenital condition. The animal in this report presented with anophthalmia associated with penile malformation. This type of association until this case report has only been described in humans and mice, and is probably caused by a mutation in the SOX2 gene, which is responsible for the protein of the same name, which makes the maturation of ocular tissues in the primitive forebrain. Thus, it is likely that such congenital alterations are the cause of the malformations observed in this animal. Maternal vitamin A deficiency, a factor known to cause ocular malformations, may also be involved in the etiology of congenital diseases. Nutritional imbalances in dogs are common in the animal’s region of origin The dog in this report had a normal life. Although it is a condition that causes blindness, dogs can have a normal life and welfare, even with bilateral anophthalmia. [ABSTRACT FROM AUTHOR]

Studies of visual receptors typically assume that only functionally similar structures are relevant to the evolution of complex eyes. This approach ignores growing evidence that different functional classes of organs often share structural and developmental patterns that pertain to biological sameness (deep homology). However, the potential relevance of non-receptor structures to eye evolution remains largely unexplored. An “ocular” feather color mechanism is described whose structural and optical features resemble those of chambered, image-forming eyes to a remarkable degree. These similarities include a laterally expanded, domed light receiving surface similar to that of an eye, an encapsulated spongy tissue mass whose coherent light scattering properties in the human-visible (destructive) and ultraviolet (constructive) wavelength ranges resemble those of cornea and lens, intervening spaces such as those with humors, and a laminar pigmented shelf whose structure and optics resemble a mirrored tapetum lucidum found behind many retinas. Fourier analysis and optical principles indicate that ocular structures adhere to the same light-handling properties regardless of higher function (receptor or signal). The extent to which chambered eyes and ocular feathers have evolved independently is surprisingly equivocal. On the one hand, broad differences in the location, composition, and development of chambered eyes and ocular feather signals suggest convergent evolution on an ocular organization. However, some level of evolutionary parallelism (generative homology) between chambered eyes and ocular feathers is implicated by similarities in constructional materials, tissue development, and signal transduction cascades. Structural, optical, and developmental similarities also occur between more primitive eyes and the colored dermal papillae responsible for avian skin ornamentation. Functional constraints on light-handling requirements, coupled with developmental constraints in high-stress environments on the body surface, may enhance the similar evolutionary outcomes in the different functional setting. Regardless of the mechanistic details, repeated evolution of eye-like structures in different functional settings reveals a biological potential to produce such organs that is much greater than would be inferred from a survey of receptor structures alone. [ABSTRACT FROM AUTHOR]

Visingsö ranked, anomalously, as the capital city of the Swedish kingdom during the 12th and 13th centuries. The castle of Näs was a royal and official residence. The presence of power on the island is likely to have impacted on its landscape. Previous research has shown that the whole of Visingsö was already under the plough in medieval times. The fact of the islanders already having pasture and forest rights beyond the island in the 13th century has been taken to indicate an early expansion of arable acreage. An almost complete mapping of the villages of Visingsö took place in the 1760s. The maps, together with the storskifte land redistribution maps prepared a few decades afterwards, show a permanently farmed landscape, but retrogressive analyses of earlier cartographical material show the 18th century mapping image to conceal an older organisation of the landscape in which arable acreage was more limited in areas where the heavy clay soil and the lighter sandy soil came together. The stiff clays characterising the shoreline zones of the island were probably broken fairly late, a process which was still in progress when the first maps were drawn. Visingsö belonged to the ard (scratch-plough) region, and ploughshares were not introduced there until the 19th century. The northern villages, however, have a longer history of tiling the clay soil and by deliberate improvement increased the tilth content. A virtually frozen village landscape from the period preceding 1400 can be seen in the map of Edboängen (Edbo Meadow), for which antiquated subdivision including regular strips were recorded by the surveyor J.P. Dukre. Here an area is clearly visible in between human settlement and infields on one side and Lake Vättern on the other which if anything must be construed as coastal pasture or boggy meadowland. Clas Tollin sees a system of big farmsteads dominating the settlement pattern of Visingsö in early medieval times. Possibly it is a big farmstead of this kind which is represented by the contiguous holdings of Storegården in the village of Ed. Field names in the surroundings, with the prefix bus-, may suggest that the farmstead was fortified. The shortage of gazing land on the island may have stemmed from restructurings connected with the introduction of two-crop rotation with a cultivated fallow. A likelier explanation can be found in the physical presence of regal power on Visingsö in early medieval times. Possibly grazing was given priority, for beef and dairy cattle for the royal household at the fortress of Näs and other royal properties on the island, and also for horses belonging to the King and his retinue, hence the grazing and forest privileges accorded the islanders on the mainland. [ABSTRACT FROM AUTHOR]

Rats are commonly used as an animal model to study glaucoma, which is induced experimentally using invasive painful procedures. Peribulbar anesthesia (PBA) is frequently used in people and domestic animals prior to ophthalmic surgeries to provide excellent perioperative analgesia. The goal of this study was to develop a PBA technique adapted to rat anatomy, to improve welfare of animals used as a glaucoma model. Eighteen rat cadavers were used to establish the optimal injection technique and the volume of injectate required. Four injection techniques using lidocaine 2% and contrast agent (1:1 volume ratio) were compared using computed tomography (CT) imaging performed before and after injection. A board-certified radiologist, masked regarding the injection techniques used, reviewed all CT images and scored injectate distribution at 4 locations: extraconal, intraconal, around the optic nerve and at the orbital fissure (scale 0-8; 0=none, 8=excellent). Injectate distribution scoring (median; range) was significantly higher (i.e., better) using the dorso-medial (5; 2-6) and medial-canthus (4.5; 2-8) techniques compared with mid-ventral (3; 2-5) and ventro-lateral (2; 1-3) techniques. A volume of 0.1 mL/100 g body weight provided overall good distribution, while a volume of 0.2 mL/100 g produced excessive exophthalmos. Presence of intracranial contrast was observed following all technique. In conclusion, PBA using the dorso-medial or medial-canthus techniques are most likely to provide local anesthesia. The intracranial contrast observed could be the result of post-mortem vessel leakage. Results of this preliminary study will be used to assess the efficacy and safety of these techniques in experimental rats. [ABSTRACT FROM AUTHOR]

Changes in refractive error during the first 3 months of life were studied retinoscopically in six Thomson gazelles (Gazella thomsoni). Animals were hand-raised to allow repeat testing over time without chemical restraint. Refraction results were correlated with ultrasound measurements of intraocular dimensions, and with values in adult gazelles. Gazelles are born hyperopic with a mean refractive error of 3.44±0.31 D. By day 50, the animals are virtually emmetropic (0.13±0.21 D) and remain so in adulthood (0.03±0.09 D). The refractive error is highly correlated with the axial length (r2=0.96) and with the vitreous chamber depth (r2=0.83), but not with anterior chamber depth. Significant with-the-rule astigmatism was recorded (P<0.001). [ABSTRACT FROM AUTHOR]

The effect of rapid thermally nitrided titanium films contacting silicided (titanium disilicided) and nonsilicided junctions has been studied in the temperature range of 800 to 900°C. The rapid thermal nitridation of titanium films used as diffusion barriers between aluminum and silicon, has a major impact on shallow junction complementary metal oxide semiconductor technologies. During the process of rapid thermal nitridation, the dopants in the junctions undergo a redistribution and affect the electrical properties of shallow junction structures. This work focuses on using novel contact resistance structures to measure the variation in electrical parameters for rapid thermally nitrided titanium films annealed at different temperatures. The self-aligned silicide (salicide) junctions in this study were formed using rapid thermally annealed titanium films. Electrical contact resistance testers were used to measure the interface contact resistance between the salicide and silicon, as well as between the metal and the salicide. The results show that the interface contact resistance to the p diffused salicided junctions increases with rapid thermal nitridation of the additional titanium film, whereas the interface contact resistance to the n diffused salicided junction shows a decrease. Further, as a function of the rapid thermal annealing temperature (for fixed titanium thickness), the nonsalicided diffusions show an increase in the interface contact resistance. The boron profiles at the TiSi/Si interface obtained using secondary ion mass spectroscopy show an excellent qualitative agreement with the electrical results for each of the conditions discussed. The films were also characterized using Rutherford back-scattering spectrometry and transmission electron microscopy and the results show good agreement with the measured variation in electrical parameters. These results also show that as the anneal temperature is increased, the TiN thickness increases, further the change in the silicide/silicon interface position with the nitridation of the additional titanium layer was verified. [ABSTRACT FROM AUTHOR]