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Paleoclimate perspectives on contemporary climate change
Get PDFPaleoclimate data have informed contemporary climate science, and could do so more extensively. Quaternary data record glacial–interglacial cycles paced by variations in Earth's orbit. Faster climate changes include repeated warming–cooling (Dansgaard–Oeschger) cycles during glacial times as well as abrupt glacial terminations, suggesting repeated crossings of a tipping point. Climate models reproduce some key features of past climate change but not others, including patterns of orbitally forced precipitation changes and linkages between different modes of climate variability. Land ecosystem records document plant species’ resilience to rapid climate change, in contrast to large mammals' vulnerability; multiple roles of natural wildfires; and effects of low glacial CO2 on vegetation and fire. Dansgaard–Oeschger cycles constrain biogeochemical feedbacks, showing large increases of CH4 and N2O with warming and suggesting destabilizing feedbacks through land surface albedo under glacial conditions. Lessons for conservation include recognizing “novel” ecosystems as normal and respecting the paramount role of species movements as responses to rapid climate change
Iran and Its proxies: attribution and state responsibility
Get PDFIran has invested heavily in proxy militias since the regime's founding in 1979. In the decades that followed, groups such as Hezbollah in Lebanon, Shi'a militias in Iraq and Syria, and the Houthis in Yemen have projected Iran's influence across the region. Today, Iran's proxy network is considerably weakened due to Israel's military actions following October 7, 2023, and the fall of the Assad regime in Syria. Yet the Houthis' attacks on Israel and against Red Sea shipping demonstrate how Iran's support to these groups continues to facilitate their conduct in violation of international law. This article examines Iran's potential responsibility for acts on the part of its proxies that violate its international legal obligations. It assesses first the grounds on which the proxies' acts could be attributable to Iran before addressing Iran's potential responsibility for aiding and assisting its proxies' harmful conduct. Finally, the article considers Iran's potential breach of primary norms of international law, such as the prohibition on the use of force, through its support to the proxy groups. The analysis highlights the varied relationships between Iran and its proxies and the difficulties that arise when seeking to hold Iran to account. Many of the proxy groups act with a degree of independence that precludes the attribution of their conduct to Iran. Other States might therefore be better served by calling Tehran out for its violation of primary norms of international law, including Common Article 1 to the Geneva Conventions
nextGEMS: entering the era of kilometer-scale Earth system modeling
Get PDFThe Next Generation of Earth Modeling Systems (nextGEMS) project aimed to produce multidecadal climate simulations, for the first time, with resolved kilometer-scale (km-scale) processes in the ocean, land, and atmosphere. In only 3 years, nextGEMS achieved this milestone with the two km-scale Earth system models, ICOsahedral Non-hydrostatic model (ICON) and Integrated Forecasting System coupled to the Finite-volumE Sea ice-Ocean Model (IFS-FESOM). nextGEMS was based on three cornerstones: (1) developing km-scale Earth system models with small errors in the energy and water balance, (2) performing km-scale climate simulations with a throughput greater than 1 simulated year per day, and (3) facilitating new workflows for an efficient analysis of the large simulations with common data structures and output variables. These cornerstones shaped the timeline of nextGEMS, divided into four cycles. Each cycle marked the release of a new configuration of ICON and IFS-FESOM, which were evaluated at hackathons. The hackathon participants included experts from climate science, software engineering, and high-performance computing as well as users from the energy and agricultural sectors. The continuous efforts over the four cycles allowed us to produce 30-year simulations with ICON and IFS-FESOM, spanning the period 2020–2049 under the SSP3-7.0 scenario. The throughput was about 500 simulated days per day on the Levante supercomputer of the German Climate Computing Center (DKRZ). The simulations employed a horizontal grid of about 5 km resolution in the ocean and 10 km resolution in the atmosphere and land. Aside from this technical achievement, the simulations allowed us to gain new insights into the realism of ICON and IFS-FESOM. Beyond its time frame, nextGEMS builds the foundation of the Climate Change Adaptation Digital Twin developed in the Destination Earth initiative and paves the way for future European research on climate change
Babesia species detected in deer from Southwest England
Get PDFBabesia species have been detected in deer across Europe, and deer grazing in the same location as livestock may increase the risk of transmission of species such as the parasite B. divergens. Bovine babesiosis and the cost of treatment increase the economic burden on farmers. To determine the presence of Babesia species in wild deer populations in the counties of Devon and Somerset, Southwest England, blood samples were collected from red (Cervus elaphus) and fallow (Dama dama) deer as part of routine deer management during late 2022 and early 2023. Extracted DNA samples were tested for the presence of piroplasm DNA by polymerase chain reaction. Amplicons were sequenced to identify the species present in samples based on single-nucleotide polymorphisms within the 18S rRNA gene. Two species of Babesia were detected: a B. divergens/capreoli species detected in both red and fallow deer and a Babesia species related to B. odocoilei in a single fallow deer, a species that has been detected in deer across Great Britain. The presence of B. divergens/capreoli in deer blood from these areas provides evidence that wild deer could serve as a reservoir for this parasite within Southern England
Rotaxanes in lipid environments
No full textRotaxanes are a unique architecture in chemistry, consisting of two components—a thread
and a macrocycle—which are bound together mechanically. The macrocycle can freely
move along the thread structure, the motion of which can be modulated by structural
adjustments of the individual components. This motion can be coupled to a secondary
process to develop molecular machines, which have been used in catalysis and have
potential applications as transmembrane therapeutics. Rotaxanes have been utilised as ion
transporters, where the shuttling motion is theorised to ferry ions across the lipid bilayer.
The rate of shuttling in these rotaxanes has been linked to their transport capabilities but
have never been directly calculated in a lipid environment.
In this thesis, a series of rotaxane anion carriers were developed, where shuttling away from
the anion binding site was required for successful transmembrane transport. These
rotaxanes were categorised into three shuttling regimes. The fastest shuttling rotaxane has
transport capabilities most similar to its non-interlocked thread, and slower shuttling
rotaxanes showed greater divergence. Novel variable-temperature (VT) transport
experiments were carried out in two different membrane environments. In a more fluidic
membrane, the transport rate of the rotaxanes increased more rapidly with temperature than
the non-interlocked threads.
Another set of rotaxanes were developed and their shuttling rate was directly monitored in
a lipid environment using VT 19F NMR. An eight-fold reduction in shuttling rate was
observed on going from solution to micellar state. The study is the first direct observation
of shuttling rates of rotaxanes in lipid membranes, which is essential information required
for the development of transmembrane molecular machinery based on the mechanical bond
for biomedical applications and beyond
Optimality approaches linking fire-related plant traits and ecosystem responses to climate change
No full textFire is a fundamental ecological and evolutionary process that shapes the structure,
function, and resilience of ecosystems worldwide. Yet, global fire models typically
treat vegetation as passive fuel, neglecting plant adaptive strategies and their
feedbacks on fire behaviour and recovery following fire. This thesis advances a
predictive, trait-based understanding of fire by integrating global plant trait data,
remote sensing, and eco-evolutionary optimality (EEO) theory into a unified
framework linking environmental drivers, fire regimes, plant traits, and ecosystem
outcomes.
A novel EEO-based classification of global pyroclimates has been developed, which
shows that the seasonal dynamics of fuel accumulation and drying, captured through
gross primary production (GPP) and vapour pressure deficit (VPD), provide a simple
yet mechanistic basis for distinguishing fire behaviour across biomes (Chapter 4). Fire
behaviour is shown to act as a selective filter on plant strategies. The abundance of
resprouting woody species across Europe and Australia, for example, is strongly
related to fire return time, intensity, and type, with resprouters most common under
frequent, intense crown fires (Chapter 2). Key flammability-related traits of woody
plants, including specific leaf area (SLA), leaf dry matter content (LDMC), and leaf C:N
ratio, vary systematically across pyroclimates (Chapter 5). In a global analysis of more
than 10,000 fires, post-fire recovery of photosynthetic activity as measured using solar-induced chlorophyll fluorescence (SIF) is shown to be related to plant traits, such as
pre-fire productivity and the abundance of resprouting, as well as fire characteristics
and post-fire climate conditions (Chapter 3).
These findings demonstrate a coherent causal chain: environmental drivers shape fire
regimes, fire acts as an evolutionary filter on plant traits, and traits determine post-fire
ecosystem function and resilience. This thesis provides both empirical evidence and a
theoretical framework for integrating trait–fire relationships into Earth system models,
providing insights on moving beyond empirical parameterisation toward simplified,
mechanistic representations. By grounding fire ecology in biophysical constraints and
eco-evolutionary principles, this research enhances our ability to predict vegetation–
fire feedbacks and informs management strategies in an era of intensifying global fire
activity
Consumers' perception towards foods submitted to sustainable non-thermal food processing technologies
No full textThere has been an increased interest in foods that are more sustainable,
healthier, minimally processed, with higher nutritional and sensory quality, and
with extended shelf life. Non-thermal technologies, such as High-Pressure (HPP),
Non-thermal Plasma (NTP), Pulsed Electric Field (PEF), and Ultrasound, offer
potential solutions to these demands. However, consumers are somewhat
sceptical of new technologies, and to guarantee the success of the technology, it
is necessary to help consumers understand the benefits of the technology in
order to evoke positive attitudes towards it. This study aimed to evaluate risk
perception, assess consumers' choices and willingness to pay, and evaluate
consumers’ evoked emotional and sensory profiles of products developed using
non-thermal technologies.
This research investigated consumer risk perception through a survey conducted
in Portugal, Germany, and the United Kingdom, involving more than 400
consumers per country, and presented twelve constructs based on an Ecological
Framework. It revealed that risk perception varied by technology and country,
although food technology neophobia, perceived relative severity, and trust
consistently influenced it. Second, choice-based conjoint analysis (CBCA) was
conducted with over 240 participants per country (Portugal, UK, and Germany)
to test consumer preferences for the type of technology (non-thermal,
conventional or technology not defined) and price (low or high), under both
purchase and consumption-evoked contexts, using burgers (HPP), liquid egg
(Thermossonication - TS), oregano (NTP), and oat drink (PEF) as the food types.
Results showed a general preference for conventional processing and lower
prices, with notable exceptions: Portuguese and UK consumers preferred HPP
burgers, and German consumers favoured TS eggs. Technology Neophobia did
not significantly affect choice. Third, sensory studies with 75 German consumers
revealed that PEF-treated oat drinks maintained liking levels comparable to those
of thermal controls. In contrast, 80 German consumers found that
Manothemossonication (MTS) processing of eggs reduced their liking,
suggesting that they are not suitable for standalone products, but it would be
interesting to test if this perception would be seen if they were used as a
ingredient. Finally, evoked emotional and sensory profiling in Portugal
demonstrated that NTP had a positive impact on the sensory and evoked
emotional attributes of onion flakes and whole black pepper. However, there was
no significant effect on these profiles when using NTP for ground black pepper
and oregano, nor when using HPP for plant-based burgers. Across studies,
sensory and evoked emotional responses were closely linked to overall liking,
with positive emotions associated with higher acceptance; however it could also
be seen a beyond liking value in which positive emotions were associated with
attributes that were not close to liking.
Together, these findings highlight the importance of considering consumers from
the beginning of novel technology development, evaluating their risk perception,
choices, and sensory preferences. It shows that the consumer risk perception
and choice are influenced by cultural context and technology, and this should be
taken into consideration when communicating about foods produced with non-thermal technologies
Environmental and social impacts of self-financed solar PV adoption in rural Zambia: Insights from mopane worms, mushrooms, fishing, bushmeat and ethnomedicine
Get PDFThis study, which is the first to study the relationship between Solar PV adoption in rural areas, and non-timber forest products (NTFPs), examines the environmental and social impacts of self-financed solar photovoltaic (PV) adoption in rural Zambia, with a focus on Mopane worms, mushrooms, fishing, bushmeat, and ethnomedicine - key NTFPs that rural households harvest for consumption and income generation. Qualitative research methods, including interviews and focus group discussions, were conducted across three geographically distinct and off-grid rural areas: Mkushi Rural (Central Province), Kapiri Rural (Central Province), and Chongwe Rural (Lusaka Province). These locations were selected for their relative isolation and lack of access to the national power grid.
Using the novel Rural Development Stakeholder Hybrid Adoption Model (RUDSHAM), this research explores the relationship between solar PV adoption and NTFP-based income. It highlights how NTFPs enable households to self-finance solar PV systems, reducing reliance on unsustainable biomass fuels while enhancing energy access. The paper also assesses the sustainability and scalability of NTFP-derived income.
Findings reveal a dual impact: while NTFPs are critical for financing solar PV adoption, their commercialization presents ecological risks, including overharvesting, habitat degradation, and biodiversity loss. Solar PV adoption contributes socio-economic benefits, such as reduced energy costs and improved household well-being, but exacerbates community tensions due to competition over limited NTFP resources.
To address these challenges, the study advocates for integrated strategies that combine renewable energy adoption with sustainable resource management. By emphasizing community-led governance and sustainable harvesting practices, it proposes a framework that aligns rural energy transitions with environmental conservation. The findings provide actionable insights for policymakers and development practitioners, contributing to the broader discourse on addressing energy poverty and ecological sustainability across Sub-Saharan Africa and similar rural contexts globally