scholarly journals Head-bobbing in the Ring-billed Gull (Larus delawarensis)

2016 ◽  
Vol 130 (2) ◽  
pp. 174
Author(s):  
Thomas J Lisney ◽  
Nikolaus F Troje
Keyword(s):  
Visual Perception ◽  
Significant Role ◽  
Strong Evidence ◽  
Functional Significance ◽  
Visual Detection ◽  
Food Items ◽  
Larus Delawarensis ◽  
Head Bobbing ◽  
Common Behaviour ◽  
Do So

Many birds bob their head as they walk or run on the ground. The functional significance of this behaviour is unclear, but there is strong evidence that it plays a significant role in enhancing visual perception. If head-bobbing is advantageous, however, then it is a puzzle that some birds do not head-bob. As a group, gulls (Laridae) are among the birds that reportedly do not head-bob,yet here we report head-bobbing among Ring-billed Gulls (Larus delawarensis), observed and filmed in Ontario, when walking relatively slowly while foraging on the ground. This suggests that head-bobbing plays a key role in the visual detection of food items in this species. We suggest that head-bobbing may be a relatively common behaviour in foraging Ring-billed Gulls and speculate that other gulls (and indeed other birds) previously thought not to head-bob may in fact do so under certain circumstances.

scholarly journals Causal modulation of right hemisphere fronto-parietal phase synchrony with Transcranial Magnetic Stimulation during a conscious visual detection task

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Chloé Stengel ◽  
Marine Vernet ◽  
Julià L. Amengual ◽  
Antoni Valero-Cabré
Keyword(s):  
Transcranial Magnetic Stimulation ◽  
Visual Perception ◽  
Frequency Band ◽  
Magnetic Stimulation ◽  
Visual Detection ◽  
Detection Task ◽  
Oscillatory Activity ◽  
Top Down ◽  
The Right ◽  
High Beta

AbstractCorrelational evidence in non-human primates has reported increases of fronto-parietal high-beta (22–30 Hz) synchrony during the top-down allocation of visuo-spatial attention. But may inter-regional synchronization at this specific frequency band provide a causal mechanism by which top-down attentional processes facilitate conscious visual perception? To address this question, we analyzed electroencephalographic (EEG) signals from a group of healthy participants who performed a conscious visual detection task while we delivered brief (4 pulses) rhythmic (30 Hz) or random bursts of Transcranial Magnetic Stimulation (TMS) to the right Frontal Eye Field (FEF) prior to the onset of a lateralized target. We report increases of inter-regional synchronization in the high-beta band (25–35 Hz) between the electrode closest to the stimulated region (the right FEF) and right parietal EEG leads, and increases of local inter-trial coherence within the same frequency band over bilateral parietal EEG contacts, both driven by rhythmic but not random TMS patterns. Such increases were accompained by improvements of conscious visual sensitivity for left visual targets in the rhythmic but not the random TMS condition. These outcomes suggest that high-beta inter-regional synchrony can be modulated non-invasively and that high-beta oscillatory activity across the right dorsal fronto-parietal network may contribute to the facilitation of conscious visual perception. Our work supports future applications of non-invasive brain stimulation to restore impaired visually-guided behaviors by operating on top-down attentional modulatory mechanisms.

scholarly journals Consumption of unregulated food items (false morels) and risk for neurodegenerative disease (amyotrophic lateral sclerosis)

2020 ◽  
pp. 94-99
Author(s):  
P.S. Spencer ◽  
Keyword(s):  
Amyotrophic Lateral Sclerosis ◽  
Free Radicals ◽  
Environmental Factors ◽  
Neurodegenerative Disease ◽  
Strong Evidence ◽  
Western Europe ◽  
World War ◽  
Food Items ◽  
Sporadic Als ◽  
Lateral Sclerosis

Unknown environmental factors are thought to contribute to the etiology of sporadic forms of amyotrophic lateral sclerosis (ALS). Strong evidence supporting this view is found in the post-World War decline and disappearance of highincidence ALS in three Western Pacific populations that formerly utilized neurotoxic cycad seed as a traditional source of food and/or medicine. The principal toxins in cycads (cycasin) and in False Morel mushrooms (gyromitrin) generate methyl free radicals that damage DNA and cause mutation and uncontrolled division of cycling cells and degeneration of late-/postmitotic neurons. Since False Morels are scavenged for food in Finland, Russia, Spain, and USA, research studies are underway in Western Europe and USA to determine if the practice is associated with sporadic ALS.

15. Development Aid and Global Justice

2021 ◽  
pp. 218-232
Author(s):  
William Abel ◽  
Elizabeth Kahn ◽  
Tom Parr ◽  
Andrew Walton
Keyword(s):  
Significant Role ◽  
Global Justice ◽  
Development Aid ◽  
Global Poverty ◽  
Global Order ◽  
Do So

This chapter examines whether affluent states should commit significant funds to alleviate poverty abroad. It argues not only that they should, but also that their duties to those who live in poverty go far beyond this. This argument in favour of development aid is based on the idea that an individual has a duty to prevent something very bad from happening when they can do so at little cost to themselves. The chapter then highlights that the global order plays a significant role in the persistence of global poverty, and this further supports the case for development aid. It also considers the claim that states should prioritize meeting the claims of their own members ahead of the claims of those who live abroad. The chapter shows that, even if this is true, it does not undermine the case for committing significant funds to alleviate global poverty.

Combined usage of stable isotopes and GPS-based telemetry to understand the feeding ecology of an omnivorous bird, the Ring-billed Gull (Larus delawarensis)

2013 ◽  
Vol 91 (10) ◽  
pp. 689-697 ◽  
Author(s):  
É. Caron-Beaudoin ◽  
M.-L. Gentes ◽  
M. Patenaude-Monette ◽  
J.-F. Hélie ◽  
J.-F. Giroux ◽  
...  
Keyword(s):  
Stable Isotope ◽  
Feeding Ecology ◽  
Blood Cells ◽  
Urban Areas ◽  
Dietary Habits ◽  
Treatment Plant ◽  
Gps Tracking ◽  
Food Items ◽  
Larus Delawarensis ◽  
Positive Correlations

The aim of the present study was to investigate the feeding ecology of an omnivorous bird, the Ring-billed Gull (Larus delawarensis Ord, 1815), breeding in a highly urbanized and heterogeneous landscape (Montréal area, Quebec, Canada). We used gastrointestinal (G.I.) tract content analysis, GPS-based tracking information, and stable isotope profiles of carbon (δ13C) and nitrogen (δ15N) in selected tissues and major food items. Based on GPS tracking data (1–3 days), Ring-billed Gulls were categorized according to their use of three main foraging habitats: agricultural, St. Lawrence River, and anthropogenic (comprising urban areas, landfills, and wastewater treatment plant basins). Ring-billed Gulls that foraged predominantly in anthropogenic habitats exhibited significantly lower δ15N in blood cells and higher total C to N ratios (C:N) in liver. These lower δ15N and higher C:N ratios were characteristic of profiles determined in food items consumed by Ring-billed Gulls at these urbanized sites (e.g., processed foods). The strong positive correlations between δ13C and δ15N in Ring-billed Gull tissues (plasma, blood cells, and liver) that differed in isotopic turnover times, as well as the strong positive correlations in both δ13C and δ15N between tissue pairs, indicated that Ring-billed Gulls exhibited conserved dietary habits throughout the nesting period. This study demonstrates that combining conventional dietary examination, tissue stable isotope analysis, and fine-scale GPS tracking information may improve our understanding of the large intrapopulation variations in foraging behaviour (and isotopic profiles) commonly observed in omnivorous birds.

scholarly journals Studies of linkage in populations. X. Altitude and autosomal gene arrangements in Drosophila robusta

1993 ◽  
Vol 61 (1) ◽  
pp. 9-20 ◽  
Author(s):  
Max Levitan ◽  
Sonja J. Scheffer
Keyword(s):  
Significant Role ◽  
Significant Variation ◽  
Autosomal Gene ◽  
Previous Evidence ◽  
Its Gene ◽  
Consistent Change ◽  
Drosophila Robusta ◽  
Do So

SummaryData are presented concerning the gene arrangements in the second and third chromosomes of Drosophila robusta in eight altitudinal transects. A consistent change is the increase in the arrangement 2L-3, particularly in the linkage combination 2L-3.2R, with increasing altitude. The reciprocal decrease with increasing altitude affects several different 2-left arrangements, most consistently 2L-1. The arrangements of 2-right show no significant variation with altitude, and those of 3-right do so only in a few samples of the two northern transects studied, none in any of the southern ones. These results confirm previous evidence for the significant role of the arrangements of the left arm of the second chromosome in the adaptations of this species to altitude and suggest further that interactions of linked arrangements are involved in these adaptations. The data also indicate that the factors responsible for the altitudinal adaptations of this species are in many cases not the same ones that are responsible for variations in its gene arrangements with latitude.

scholarly journals Investigation of CIE color spaces for differences in color differentiation thresholds in different regions of the color locus

2021 ◽  
Vol 24 (3) ◽  
pp. 107-110
Author(s):  
Leonid D. Lozhkin ◽  
Alexander A. Kuzmenko
Keyword(s):  
Visual Perception ◽  
Significant Role ◽  
Color Space ◽  
Color Difference ◽  
International Commission ◽  
Color Spaces ◽  
Transmission Systems ◽  
Color Coordinates ◽  
Cie Lab

The equidistance of the color space plays a significant role in determining the color difference in color transmission systems. Strictly equal contrasting color spaces can be considered only those color spaces in which equal changes in the visual perception of color are provided with an equal change in the color coordinates in this color space. Currently, the International Commission on Lighting (CIE) has adopted a number of color spaces called equal-contrast. The article presents the results of the study of color spaces adopted by CIE for equal contrast, i.e. on the differences in the thresholds of color differentiation in different areas of the color locus. The article investigated such color spaces as CIE 1931 (RGB), CIE 1931 (x, y), CIE 1960 (u, v), CIE 1976 (u*, v*), CIE LAB (a*, b*).

scholarly journals Christianity and Indigenisation in Africa

2021 ◽  
Vol 1 (4) ◽  
pp. 18-30
Author(s):  
M. A. Masoga ◽  
A. Nicolaides
Keyword(s):  
Significant Role ◽  
Daily Living ◽  
Early Church ◽  
Body Of Christ ◽  
Traditional Religion ◽  
African Continent ◽  
Way Of Life ◽  
Spiritual Consciousness ◽  
The Church ◽  
Do So

In a quest for greater coherence between parochial identities, culture and Christianity, there exists an African consciousness which seeks to indigenise and decolonise Christianity. Africans are profoundly religious people who view their faith as part of their way of life, as strengthening their cultures and providing a moral compass for daily living. In efforts to transform society, the Christian religion has played a significant role in the path to African development. Christianity in Africa dates to the very inception of the church. Africans consequently played a crucial role in establishing the doctrines and theology of the early church. While African Traditional religion (ATR) is paramount, it is the purpose of this article to suggest that the Christian faith has and continuous to play a significant role on the African continent in its development. While there are many indigenous African beliefs, these have been to a large extent supported by Christianity in a quest to systematize novel knowledge and promote peace and tolerance across the continent. Many Africans have sought facets of Christianity that are similar to their religious and personal practices and continue to do so. Thus, while there exist numerous similarities and also differences between Christianity and ATR, it is imperative to preserve old-style regional distinctiveness and Christianity as the unifying rudiments in nation building endeavours and in efforts to spread the gospel of Jesus Christ. Africans can and should come to comprehend the Triune Godhead as being consistent with their own spiritual consciousness and existential veracities. Indigenization of Christianity requires enculturation and essentially an understanding that it is indeed ecumenical and also embraces diversity and fundamentally requires viewing Holy Scriptures and the truths they propound as being applicable to any context and cultural milieu across the ages. Christians after all espouse a faith in the Ekklesia or body of Christ for all its people who are the Laos of God.

scholarly journals Aan tafel in het Oude Mannenhuis te Delft

Paleo-aktueel ◽  
2018 ◽  
pp. 103-114
Author(s):  
Merit Hondelink
Keyword(s):  
Early Modern ◽  
Exotic Species ◽  
The Elderly ◽  
Historical Documents ◽  
Elderly Men ◽  
Edible Plant ◽  
Food Items ◽  
Food Purchase ◽  
The Town ◽  
Do So

What’s for dinner at the Oude Mannenhuis? This paper focuses on providing a nuanced picture of the daily meal consumed at the Oude Mannenhuis, an almshouse for elderly men in Early Modern Delft (1411-1792). It aims to do so by combining historical documents dealing with food-purchase orders and archaeobotanical macro remains taken from the cesspits. The historical documents, written by the steward, suggest a frugal and monotonous diet, which appears to be incomplete as it lacks generic food items such as fruit, vegetables, herbs and spices known to have been consumed during the medieval and Early Modern periods. Yet the additional archaeobotanical data shows that at least 43 edible plant species were consumed by the residents of the Oude Mannenhuis. Most of these species are indigenous and were probably grown within and around the town of Delft, though some exotic species were also present. This combined research shows a more nuanced picture of the daily menu consumed by the elderly men of the Oude Mannenhuis.

scholarly journals Visual Perception from Object Scanning as Revealed by Electrooculography

Ophthalmology ◽  
2018 ◽  
pp. 98-114
Author(s):  
Anwesha Banerjee ◽  
Ankita Mazumder ◽  
Poulami Ghosh ◽  
D. N. Tibarewala
Keyword(s):  
Eye Movements ◽  
Visual Perception ◽  
Field Of View ◽  
Visual Environment ◽  
Human Beings ◽  
Fixational Eye Movements ◽  
Visual Processes ◽  
Points Of Interest ◽  
Do So

We the human beings are blessed by the nature to become well competent for performing highly precise and copious visual processes with how ever a restricted field of view. Howbeit, this process of visual perception is, to a great extent, controlled by the saccades or more commonly the eye movements. The positioning and accommodation of eyes allows an image to be placed (or fixed) in the fovea centralis of the eyes but although we do so to fix our gaze at a particular object, our eyes continuously move. Even though these fixational eye movements includes magnitude that should make them visible to us yet we remain oblivious to them. Microsacades, drifts and tremors that occurs frequently during fixational eye movements, contribute largely to the visual perception. We use saccades several times per second to move the fovea between points of interest and build an understanding of our visual environment.

scholarly journals Do MicroRNAs Modulate Visceral Pain?

2018 ◽  
Vol 2018 ◽  
pp. 1-10 ◽  
Author(s):  
Zhuo-Ying Tao ◽  
Yang Xue ◽  
Jin-Feng Li ◽  
Richard J. Traub ◽  
Dong-Yuan Cao
Keyword(s):  
Significant Role ◽  
Strong Evidence ◽  
Recent Progress ◽  
Target Genes ◽  
Visceral Pain ◽  
Therapeutic Targets ◽  
The Past ◽  
Complex Interactions ◽  
Pathological Conditions ◽  
Posttranscriptional Level

Visceral pain, a common characteristic of multiple diseases relative to viscera, impacts millions of people worldwide. Although hundreds of studies have explored mechanisms underlying visceral pain, it is still poorly managed. Over the past decade, strong evidence emerged suggesting that microRNAs (miRNAs) play a significant role in visceral nociception through altering neurotransmitters, receptors and other genes at the posttranscriptional level. Under pathological conditions, one kind of miRNA may have several target mRNAs and several kinds of miRNAs may act on one target, suggesting complex interactions and mechanisms between miRNAs and target genes lead to pathological states. In this review we report on recent progress in examining miRNAs responsible for visceral sensitization and provide miRNA-based therapeutic targets for the management of visceral pain.

Sign in / Sign up

Export Citation Format

Share Document