scholarly journals Assessing host extinction risk following exposure to Batrachochytrium dendrobatidis

2014 ◽  
Vol 281 (1785) ◽  
pp. 20132783 ◽  
Author(s):  
Stilianos Louca ◽  
Margarita Lampo ◽  
Michael Doebeli
Keyword(s):  
Batrachochytrium Dendrobatidis ◽  
Extinction Risk ◽  
Life Stage ◽  
Adult Life ◽  
Host Population ◽  
Amphibian Conservation ◽  
Relevant Parameter ◽  
Wildlife Diseases ◽  
Host Extinction

Wildlife diseases are increasingly recognized as a major threat to biodiversity. Chytridiomycosis is an emerging infectious disease of amphibians caused by the fungus Batrachochytrium dendrobatidis ( Bd ). Using a mathematical model and simulations, we study its effects on a generic riparian host population with a tadpole and adult life stage. An analytical expression for the basic reproduction quotient, Q o , of the pathogen is derived. By sampling the entire relevant parameter space, we perform a statistical assessment of the importance of all considered parameters in determining the risk of host extinction, upon exposure to Bd . We find that Q o not only gives a condition for the initial invasion of the fungus, but is in fact the best predictor for host extinction. We also show that the role of tadpoles, which in some species tolerate infections, is ambivalent. While tolerant tadpoles may provide a reservoir for the fungus, thus facilitating its persistence or even amplifying its outbreaks, they can also act as a rescue buffer for a stressed host population. Our results have important implications for amphibian conservation efforts.

scholarly journals Probiotic treatment restores protection against lethal fungal infection lost during amphibian captivity

2016 ◽  
Vol 283 (1839) ◽  
pp. 20161553 ◽  
Author(s):  
Jordan G. Kueneman ◽  
Douglas C. Woodhams ◽  
Reid Harris ◽  
Holly M. Archer ◽  
Rob Knight ◽  
...  
Keyword(s):  
Batrachochytrium Dendrobatidis ◽  
Life Stage ◽  
Skin Microbiome ◽  
Janthinobacterium Lividum ◽  
Probiotic Treatment ◽  
In Captivity ◽  
Boreal Toads ◽  
Inhibitory Bacteria

Host-associated microbiomes perform many beneficial functions including resisting pathogens and training the immune system. Here, we show that amphibians developing in captivity lose substantial skin bacterial diversity, primarily due to reduced ongoing input from environmental sources. We combined studies of wild and captive amphibians with a database of over 1 000 strains that allows us to examine antifungal function of the skin microbiome. We tracked skin bacterial communities of 62 endangered boreal toads, Anaxyrus boreas , across 18 time points, four probiotic treatments, and two exposures to the lethal fungal pathogen Batrachochytrium dendrobatidis ( Bd ) in captivity, and compared these to 33 samples collected from wild populations at the same life stage. As the amphibians in captivity lost the Bd -inhibitory bacteria through time, the proportion of individuals exposed to Bd that became infected rose from 33% to 100% in subsequent exposures. Inoculations of the Bd -inhibitory probiotic Janthinobacterium lividum resulted in a 40% increase in survival during the second Bd challenge, indicating that the effect of microbiome depletion was reversible by restoring Bd -inhibitory bacteria. Taken together, this study highlights the functional role of ongoing environmental inputs of skin-associated bacteria in mitigating a devastating amphibian pathogen, and that long-term captivity decreases this defensive function.

‘And all my children?’

2018 ◽  
Author(s):  
Charlotte Scott
Keyword(s):  
Early Modern ◽  
Life Stage ◽  
Early Modern Period ◽  
Life Stages ◽  
Cultural Imagination ◽  
Modern Period

Beginning with an exploration of the role of the child in the cultural imagination, Chapter 1 establishes the formative and revealing ways in which societies identify themselves in relation to how they treat their children. Focusing on Shakespeare and the early modern period, Chapter 1 sets out to determine the emotional, symbolic, and political registers through which children are depicted and discussed. Attending to the different life stages and representations of the child on stage, this chapter sets out the terms of the book’s enquiry: what role do children play in Shakespeare’s plays; how do we recognize them as such—age, status, parental dynamic—and what are the effects of their presence? This chapter focuses on how the early moderns understood the child, as a symbolic figure, a life stage, a form of obligation, a profound bond, and an image of servitude.

Touring for peace: the role of dual-narrative tours in creating transnational activists

2019 ◽  
Vol 5 (2) ◽  
pp. 200-218 ◽  
Author(s):  
Emily Maureen Schneider
Keyword(s):  
Attitude Change ◽  
Past Research ◽  
Host Population ◽  
Contact Hypothesis ◽  
Racial Groups ◽  
Content Type ◽  
Governmental Organizations ◽  
Non Governmental Organizations ◽  
Peace And Justice

Purpose Scholarship on the contact hypothesis and peacebuilding suggests that contact with marginalized ethnic and racial groups may reduce prejudice and improve opportunities for conflict resolution. Through a study of dual-narrative tours to Israel/Palestine, the purpose of this paper is to address two areas of the debate surrounding this approach to social change. First, past research on the effectiveness of contact-based tourism as a method to change attitudes is inconclusive. Travel to a foreign country has been shown to both improve and worsen tourists’ perceptions of a host population. Second, few scholars have attempted to link contact-based changes in attitudes to activism. Design/methodology/approach Through an analysis of 218 post-tour surveys, this study examines the role of dual-narrative tours in sparking attitude change that may facilitate involvement in peace and justice activism. Surveys were collected from the leading “dual-narrative” tour company in the region, MEJDI. Dual-narrative tours uniquely expose mainstream tourists in Israel/Palestine to Palestinian perspectives that are typically absent from the majority of tours to the region. This case study of dual-narrative tours therefore provides a unique opportunity to address the self-selecting bias, as identified by contact hypothesis and tourism scholars, in order to understand the potential impacts of exposure to marginalized narratives. Findings The findings of this study suggest that while these tours tend to engender increased support for Palestinians over Israelis, their most salient function appears to be the cultivation of empathy for “both sides” of the conflict. Similarly, dual-narrative tours often prompt visitors to understand the conflict to be more complex than they previously thought. In terms of activism, tourists tend to prioritize education-based initiatives in their plans for post-tour political engagement. In addition, a large number of participants articulated commitments to support joint Israeli–Palestinian non-governmental organizations and to try to influence US foreign policy to be more equitable. Originality/value These findings complicate debates within the scholarship on peacebuilding as well as within movements for social justice in Israel/Palestine. While programs that equate Israeli and Palestinian perspectives are often criticized for reinforcing the status quo, dual-narrative tours appear to facilitate nuance and universalism while also shifting tourists toward greater identification with an oppressed population. Together, these findings shed light on the ability of tourism to facilitate positive attitude change about a previously stigmatized racial/ethnic group, as well as the power of contact and exposure to marginalized narratives to inspire peace and justice activism.

Helminthofauna of the fox (Vulpes vulpes) and korsak (Vulpes corsac)

2021 ◽  
Vol 3 ◽  
pp. 28-35
Author(s):  
I.M. Abirova ◽  
N.Zh. Eleugaliyeva ◽  
G.K. Zhumagaliyeva ◽  
M.G. Gusmanov
Keyword(s):  
Vulpes Vulpes ◽  
Toxocara Canis ◽  
Host Population ◽  
Farm Animals ◽  
Wild Animals ◽  
The West ◽  
West Kazakhstan ◽  
The One ◽  
Epidemiological Significance

For humans and domestic animals, parasites of wild animals can pose a threat to health, and even life. In this regard, it is important to establish the pathways of circulation of pathogens of dangerous helminthiasis, to identify the nature of the focus and the role of wild animals in this process, since these data serve as the basis for the development of anti-parasite measures. The study of parasitic organisms of wild animals is of great importance for science and practice. In natural biocenosis, one of their joints is parasitic species, which, on the one hand, are involved in the regulation of the host population; on the other hand, they prevent the introduction and spread of new species related to the host, i.e. participate in ensuring homeostasis of biocenosis. Parasitizing in various hosts, both definitive and intermediate, helminthes can determine the number and distribution over the territory not only of these hosts, but also of other animal species associated with these hosts by trophic and other connections. The foregoing determines the relevance of the problem of studying the fauna of helminthes of wild animals in the West Kazakhstan region, which is currently under-researched. The species composition of helminthes of the fox (Vulpes vulpes) and the korsak (Vulpes corsac) in the territory of the West-Kazakhstan region region was explored. In most cases, the invasion was recorded in an associative form. Some helminthes cause serious diseases in humans and farm animals. As a result of our research, we identified 6 species of intestinal helminthes in the common fox, two of which (Alveococcus multilocularis, Toxocara canis) have epidemiological significance. In korsak, 3 types of helminthes were identified at the autopsy before the species.

scholarly journals The impact of neighborhood walkability on walking: Does it differ across adult life stage and does neighborhood buffer size matter?

2014 ◽  
Vol 25 ◽  
pp. 43-46 ◽  
Author(s):  
Karen Villanueva ◽  
Matthew Knuiman ◽  
Andrea Nathan ◽  
Billie Giles-Corti ◽  
Hayley Christian ◽  
...  
Keyword(s):  
Life Stage ◽  
Adult Life ◽  
Buffer Size ◽  
Neighborhood Walkability ◽  
Size Matter ◽  
The Impact

Development of a Young Man with Prader-Willi Syndrome and Secondary Functional Encopresis

1989 ◽  
Vol 34 (2) ◽  
pp. 123-127 ◽  
Author(s):  
Susan P.C. Carpenter
Keyword(s):  
Personality Development ◽  
Life Stage ◽  
Behavioural Therapy ◽  
Complex Problem ◽  
Prader Willi Syndrome ◽  
Case Review ◽  
Therapeutic Modalities ◽  
Eclectic Approach ◽  
Physical Abilities

A case review of a twenty-two year old man suffering from Prader-Willi Syndrome, Secondary Functional Encopresis, mental retardation and aggressive behaviour is presented. Emphasis is made in assessing this man from various developmental perspectives. This includes: personality development, cognitive development, physical abilities, sexual development and family life stage. The role of a psychiatrist in treating this complex problem is established. An eclectic approach to treatment is reviewed using many therapeutic modalities found effective with the mentally handicapped. These modalities include: group therapy, play therapy, individual psychotherapy, behavioural therapy, family therapy, and use of medication. A literature review of Prader-Willi Syndrome is included.

scholarly journals Influence of Dietary Nutrient Intake on Episodic Memory Across the Adult Life Span

2021 ◽  
Vol 13 ◽  
Author(s):  
Selene Cansino ◽  
Frine Torres-Trejo ◽  
Cinthya Estrada-Manilla ◽  
Adriana Flores-Mendoza ◽  
Gerardo Ramírez-Pérez ◽  
...  
Keyword(s):  
Episodic Memory ◽  
Life Span ◽  
Memory Performance ◽  
Life Stage ◽  
Saturated Fatty Acids ◽  
Adult Life ◽  
Middle Aged ◽  
Negative Effects ◽  
Daily Consumption ◽  
Adult Life Span

The aim of the study was to identify nutrients that have the ability to impact brain functioning and, as a consequence, influence episodic memory. In particular, we examined recollection, the ability to recall details of previous experiences, which is the episodic memory process most affected as age advances. A sample of 1,550 healthy participants between 21 and 80 years old participated in the study. Nutritional intake was examined through a food frequency questionnaire and software developed to determine the daily consumption of 64 nutrients based on food intake during the last year. Recollection was measured through a computerized source memory paradigm. First, we identified which nutrients influence recollection across the entire adult life span. Then, moderator analyses were conducted by dividing the sample into young (21–40 years old), middle-aged (41–60 years old) and older (61–80 years old) adults to establish in which life stage nutrients influence episodic memory. Across the adult life span, recollection accuracy was shown to benefit from the intake of sodium, heme, vitamin E, niacin, vitamin B6, cholesterol, alcohol, fat, protein, and palmitic, stearic, palmitoleic, oleic, gadoleic, alpha-linoleic and linoleic acid. The effects of energy, maltose, lactose, calcium and several saturated fatty acids on recollection were modulated by age; in older adults, the consumption of these nutrients negatively influenced episodic memory performance, and in middle-aged adults, only lactose had negative effects. Several brain mechanisms that support episodic memory were influenced by specific nutrients, demonstrating the ability of food to enhance or deteriorate episodic memory.

scholarly journals A DIDACTIC PERSPECTIVE ON THE FALSE TREATY OF MANIPULATION – WRITTEN BY ANA BLANDIANA

2016 ◽  
Vol 4 ◽  
pp. 311-317
Author(s):  
Florina Irina Dima
Keyword(s):  
High School ◽  
Adult Life ◽  
Contemporary History ◽  
Autobiographical Texts

The present paper aims to underline the important role of introducing contemporary reading of autobiographical texts in high-school literature classes in Romania. It mentions the concepts of Shah Saria, Debra Edwards, and Linda Andersen, and the definitions of autobiography by Philippe Lejeune, Isabel Duran, and Karl Weintraub. For demonstration, it examines the text of the Romanian writer Ana Blandiana (a pseudonym of Otilia Valeria Coman), namely the False Treaty of Manipulation, published in 2013. The didactic generosity of this book is demonstrated with mention of the thematic stratification and uniqueness of the text, and by discussing the textual reference to the Romanian contemporary history, the connections between topics within the book, and how these might serve the interest and preparedness of teenagers for their adult life. The didactic approach of the book content involves extra-, inter-, and across-textual questions, as well as detailed passages, themes, and secondary themes relevant to the study of autobiography.

scholarly journals Reference determination for demonstrative pronouns

2007 ◽  
Vol 48 ◽  
pp. 39-51 ◽  
Author(s):  
Peter Bosch ◽  
Carla Umbach
Keyword(s):  
Structural Properties ◽  
Reading Time ◽  
Current Paper ◽  
Relevant Parameter ◽  
Personal Pronouns ◽  
Corpus Study ◽  
Demonstrative Pronouns ◽  
The Subject ◽  
Reference Determination

This paper discusses results from a corpus study of German demonstrative and personal pronouns and from a reading time experiment in which we compared the interpretation options of the two types of pronouns (Bosch et al. 2003, 2007). A careful review of exceptions to a generalisation we had been suggesting in those papers (the Subject Hypothesis: "Personal pronouns prefer subject antecedents and demonstratives prefer non-subject antecedents") shows that, although this generalisation correctly describes a tendency in the data, it is quite wrong in claiming that the grammatical role of antecedents is the relevant parameter. In the current paper we argue that the generalisation should be formulated in terms of in-formation-structural properties of referents rather than in terms of the grammatical role of antecedent expressions.  

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