Widespread variation in heat tolerance and symbiont load are associated with growth tradeoffs in the coral Acropora hyacinthus in Palau

ABSTRACTClimate change is poised to dramatically change ecosystem composition and productivity, leading scientists to consider the best approaches to fostering population resilience and diversity in the face of these changes. Here we present results of a large-scale experimental assessment of bleaching resistance, a critical trait for coral population persistence as oceans warm, in 293 colonies of the coral Acropora hyacinthus across 39 reefs in Palau. We find bleaching resistant individuals originate significantly more often from warmer reefs, although they inhabit almost every reef regardless of temperature at low frequency. High levels of variation within reefs, where colonies experience similar temperatures, suggests that bleaching resistance is not solely due to phenotypic plasticity, but also involves adaptive alleles and host-symbiont interactions. To the extent that it is heritable, bleaching resistance could be used in promoting nursery growth, habitat restoration, or breeding, while employing large numbers of resistant colonies to preserve genetic variation.

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The Stern Review on Climate Change: Inconvenient Sensitivities

Energy & Environment ◽

10.1260/095830509789141461 ◽

2009 ◽

Vol 20 (5) ◽

pp. 779-798 ◽

Cited By ~ 1

Author(s):

Sergey Mityakov ◽

Christof Rühl

Keyword(s):

Climate Change ◽

Time Preference ◽

Complex Problem ◽

Policy Choices ◽

Subjective Judgement ◽

The Face ◽

Stern Review ◽

The Cost ◽

Parameter Values ◽

Considerable Discussion

Nicholas Stern's Review of “The Economics of Climate Change” (2007) triggered considerable discussion, essentially by condensing a complex problem – the question of how to act in the face of global warming – into juxtaposing two numbers, the cost of mitigation and the cost of climate change. The Review concludes that mitigation today is economically superior to adaptation tomorrow. The review was widely criticized for the assumption of a pure rate of time preference of almost zero, on which its conclusions seemed to depend. In this paper we argue first, that this assumption discriminates against current in favour of future generations. Second, we perform a sensitivity analysis to test for the extent to which the conclusions of the Review are indeed based on the assumption of a rate of time preference of almost zero. We demonstrate that the conclusions of the Review are no longer valid as soon as parameter values are used which are standard in economic analysis. Combined, these results raise a bigger question: how wise is it to base crucial policy choices on a model so dependent on a single, deeply subjective, judgement call?

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Titration and Conditional Knockdown of the prfB Gene in Escherichia coli: Effects on Growth and Overproduction of the Recombinant Mammalian Selenoprotein Thioredoxin Reductase

Applied and Environmental Microbiology ◽

10.1128/aem.02019-06 ◽

2006 ◽

Vol 73 (2) ◽

pp. 432-441 ◽

Cited By ~ 14

Author(s):

Olle Rengby ◽

Elias S. J. Arnér

Keyword(s):

Escherichia Coli ◽

Growth Rate ◽

Essential Gene ◽

Thioredoxin Reductase ◽

Lower Growth ◽

E Coli ◽

Native Promoter ◽

Lower Growth Rate ◽

The Cost ◽

Translational Termination

ABSTRACT Release factor 2 (RF2), encoded by the prfB gene in Escherichia coli, catalyzes translational termination at UGA and UAA codons. Termination at UGA competes with selenocysteine (Sec) incorporation at Sec-dedicated UGA codons, and RF2 thereby counteracts expression of selenoproteins. prfB is an essential gene in E. coli and can therefore not be removed in order to increase yield of recombinant selenoproteins. We therefore constructed an E. coli strain with the endogenous chromosomal promoter of prfB replaced with the titratable PBAD promoter. Knockdown of prfB expression gave a bacteriostatic effect, while two- to sevenfold overexpression of RF2 resulted in a slightly lowered growth rate in late exponential phase. In a turbidostatic fermentor system the simultaneous impact of prfB knockdown on growth and recombinant selenoprotein expression was subsequently studied, using production of mammalian thioredoxin reductase as model system. This showed that lowering the levels of RF2 correlated directly with increasing Sec incorporation specificity, while also affecting total selenoprotein yield concomitant with a lower growth rate. This study thus demonstrates that expression of prfB can be titrated through targeted exchange of the native promoter with a PBAD-promoter and that knockdown of RF2 can result in almost full efficiency of Sec incorporation at the cost of lower total selenoprotein yield.

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A framework for selectively breeding corals for assisted evolution

10.1101/2021.02.23.432469 ◽

2021 ◽

Author(s):

Adriana Humanes ◽

John Bythell ◽

Elizabeth Beauchamp ◽

Mitch Carl ◽

Jamie Craggs ◽

...

Keyword(s):

Climate Change ◽

Large Scale ◽

Selective Breeding ◽

Coral Cover ◽

Ex Situ ◽

Conservation Strategies ◽

Acropora Digitifera ◽

Interdisciplinary Approaches ◽

The Face

AbstractCoral cover on tropical reefs has declined during the last three decades due to the combined effects of climate change, destructive fishing, pollution, and land use change. Drastic reductions in greenhouse gas emissions combined with effective coastal management and conservation strategies are essential to slow this decline. Innovative approaches, such as selective breeding for adaptive traits combined with large-scale sexual propagation, are being developed with the aim of pre-adapting reefs to increased ocean warming. However, there are still major gaps in our understanding of the technical and methodological constraints to producing corals for such restoration interventions. Here we propose a framework for selectively breeding corals and rearing them from eggs to 2.5-year old colonies using the coral Acropora digitifera as a model species. We present methods for choosing colonies for selective crossing, enhancing early survivorship in ex situ and in situ nurseries, and outplanting and monitoring colonies on natal reefs. We used a short-term (7-day) temperature stress assay to select parental colonies based on heat tolerance of excised branches. From six parental colonies, we produced 12 distinct crosses, and compared survivorship and growth of colonies transferred to in situ nurseries or outplanted to the reef at different ages. We demonstrate that selectively breeding and rearing coral colonies is technically feasible at small scales and could be upscaled as part of restorative assisted evolution initiatives. Nonetheless, there are still challenges to overcome before selective breeding can be implemented as a viable conservation tool, especially at the post-settlement and outplanting phases. Although interdisciplinary approaches will be needed to overcome many of the challenges identified in this study, selective breeding has the potential to be a viable tool within reef managers’ toolbox to support the persistence of selected reefs in the face of climate change.

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Covid-19 transmission dynamics during the unlock phase and significance of testing

10.1101/2020.08.18.20176354 ◽

2020 ◽

Cited By ~ 2

Author(s):

Abhijit Paul ◽

Samrat Chatterjee ◽

Nandadulal Bairagi

Keyword(s):

Growth Rate ◽

Large Scale ◽

Lower Growth ◽

Epidemic Curve ◽

Large Scale Testing ◽

The Social ◽

The World ◽

The Usa ◽

History Of ◽

Lower Growth Rate

The pandemic disease Covid-19 caused by SARS-COV-2, which emerged from Wuhan, China, has established itself as the most devastating disease in the history of infectious disease, affecting 216 countries/territories across the world. Different countries have developed and adopted various policies to contain this epidemic and the most common were the social distancing and lockdown. Though some countries have come out of this pandemic, the infection is still increasing and remains very serious in the rest of the world. Even when the disease is not under control, many countries have withdrawn the lockdown and going through the phase-wise unlocking process, causing a further increment in the infection rate. In such a scenario, the role of the undetected class of infected individuals has become very crucial. The present study is an attempt to understand and estimate the possible epidemic burden during the unlock phase in the presence of an undetected class. We proposed a modified SEIR model and dissected the epidemiological status of different countries with the available data. With the initial establishment of the model with the epidemic data of four countries, which have already attained the epidemic peak, the study focused more on countries like India and the USA, where the epidemic curve is still growing, but the unlock process has started. As a straightforward result, we noticed a significant increase in the undetected and detected infected cases under the ongoing unlock phase. Under such conditions, our recalibration exercise showed that an increase in the testing could revert the existing growth rate of the infected cases to the lower growth rate of the lockdown period. Our present study emphasizes on the implementation of 3T principles, trace, test, and treat, to contain the epidemic. The significance of large scale testing in controlling the epidemic is true for both India and the USA though they have different socio-economic conditions. The use of repurposing drugs may further decrease the infected cases and help the disease controlling process. We believe our proposed strategy obtained through a mathematical model will help to make a better policy for the unlock phase.

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Relocate People to Safer Ground

Building a Resilient Tomorrow ◽

10.1093/oso/9780190909345.003.0010 ◽

2019 ◽

pp. 169-188

Author(s):

Hill and

Keyword(s):

Climate Change ◽

Sea Level Rise ◽

Sea Level ◽

Large Scale ◽

Political Stability ◽

Sudden Onset ◽

Economic Opportunity ◽

The World ◽

The Face ◽

Slow Onset

Whether the world is prepared for it or not, climate change will drive large-scale migration. The impacts of climate change—both slow-onset changes, such as sea-level rise and drought, and sudden-onset events, such as extreme storms and wildfires—push people from their homes. Managed well, migration can yield enormous benefits, offering greater opportunities for those who relocate and injecting new talent and energy into receiver communities. But climate change threatens to unleash “disruptive migration,” that is, sudden migration that could strain social, economic, and political stability. The task ahead in the face of climate change is to encourage managed, gradual migration that minimizes disruption, moves people out of harm’s way, and turns displacement into economic opportunity. This chapter outlines the strategies and tools that exist to make this possible.

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Just Societal Transformation: Perspectives of Pastoralists in the Lower Omo Valley in Ethiopia

African Handbook of Climate Change Adaptation ◽

10.1007/978-3-030-42091-8_265-2 ◽

2021 ◽

pp. 1-21

Author(s):

Sabine Troeger

Keyword(s):

Climate Change ◽

Decision Making ◽

Climate Change Adaptation ◽

Large Scale ◽

Regional Scale ◽

Global Scale ◽

Development Project ◽

The Face ◽

Local Actors ◽

Sugar Development

AbstractPastoralists’ livelihoods in Africa are highly endangered by adverse forces – the climate change being one among those. Against this background, climate change adaptation is conceptualized as strategic agency in the field of risk-laden livelihood environments, that is, agency in the face of risky options and non-calculable uncertainties.The chapter conceptualizes pastoralists’ livelihoods exposed to a four-fold hierarchy of environmental risks and forces defining the actors’ arena of strategic decision making: From the global scale of ever extending impacts by the climate change imperative, to the national scale of government policies in terms of decentralization, challenging people to govern and define their communal efforts in terms of climate change adaptation, and down to the regional scale, which in the presented case is dominated by a large-scale investment, the Kuraz Sugar Development Project, which again confronts local actors with adverse forces toward villagization and eviction from pasture grounds. Right at the end of this hierarchy and in accordance with discourses on “climate services,” the end-users and local actors, the pastoralists, are confronted with and offered a product that they can input into their decision making: cattle feed from the residues of the irrigated sugar cane. The question remains whether substantive aspects of processes turning into true environmental and social justice in terms of recognition, procedures, and distribution will be paid attention to.

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Just Societal Transformation: Perspectives of Pastoralists in the Lower Omo Valley in Ethiopia

African Handbook of Climate Change Adaptation ◽

10.1007/978-3-030-42091-8_265-1 ◽

2021 ◽

pp. 1-21

Author(s):

Sabine Troeger

Keyword(s):

Climate Change ◽

Decision Making ◽

Climate Change Adaptation ◽

Large Scale ◽

Regional Scale ◽

Global Scale ◽

Development Project ◽

The Face ◽

Local Actors ◽

Sugar Development

AbstractPastoralists’ livelihoods in Africa are highly endangered by adverse forces – the climate change being one among those. Against this background, climate change adaptation is conceptualized as strategic agency in the field of risk-laden livelihood environments, that is, agency in the face of risky options and non-calculable uncertainties.The chapter conceptualizes pastoralists’ livelihoods exposed to a four-fold hierarchy of environmental risks and forces defining the actors’ arena of strategic decision making: From the global scale of ever extending impacts by the climate change imperative, to the national scale of government policies in terms of decentralization, challenging people to govern and define their communal efforts in terms of climate change adaptation, and down to the regional scale, which in the presented case is dominated by a large-scale investment, the Kuraz Sugar Development Project, which again confronts local actors with adverse forces toward villagization and eviction from pasture grounds. Right at the end of this hierarchy and in accordance with discourses on “climate services,” the end-users and local actors, the pastoralists, are confronted with and offered a product that they can input into their decision making: cattle feed from the residues of the irrigated sugar cane. The question remains whether substantive aspects of processes turning into true environmental and social justice in terms of recognition, procedures, and distribution will be paid attention to.

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Fiscal Sustainability, Demographics, and the Social Determinants of Health Driving Intergenerational Equity

Advances in Electronic Government, Digital Divide, and Regional Development - Financial Sustainability and Intergenerational Equity in Local Governments ◽

10.4018/978-1-5225-3713-7.ch006 ◽

2018 ◽

pp. 125-147 ◽

Cited By ~ 1

Author(s):

Richard F. Callahan ◽

Mark A. Pisano

Keyword(s):

Local Government ◽

Common Pool Resources ◽

Intergenerational Equity ◽

Fiscal Sustainability ◽

Lower Growth ◽

Social Inequities ◽

The Social ◽

Lower Growth Rate ◽

The Individual ◽

The Cost

The research developed in this chapter identifies intergenerational equity as a function of three dynamics: local government fiscal sustainability, demographic drivers, and place-based health equity. Intergeneration equity is researched from three related sets of pressures: One, the cost increases threatening the fiscal sustainability. Two, demographic changes result in a lower growth rate of working population. Three, persistent social inequities linked directly to neighborhoods correlate with wide disparities in life expectancy. The research develops a deeper understanding of each of these three dynamics, including the individual impact as well as the collective impact through their interconnectedness. This combined analytic framework better identifies the institutional mechanisms that can address these issues. The chapter concludes with mapping ways for local government to move forward by applying the design principals developed from research in sustainability of common pool resources.

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