The snow and the willows : the ecological responses of the alpine dwarf shrub "Salix herbacea" to climate change

Current changes in shrub abundance in alpine and arctic tundra ecosystems are primarily driven by warming, changes in snow cover time and shifts in biotic interactions. However, while taller shrub communities are expanding, dwarf shrubs show reductions under climate warming. The aim of this thesis was to disentangle the phenological, growth and fitness response of a widespread prostrate shrub to warming and changes in snowmelt time, investigate shifts between competition and facilitation in communities along environmental stress gradients, and determine trait plasticity in response to snowmelt change. To this end, we investigated phenology, vegetative growth and reproductive traits in Salix herbacea, a widespread, long-lived alpine and arctic prostrate shrub, along its elevational and snowmelt microhabitat range over three years in Davos, Switzerland. To examine environmental drivers of trait variation, community interactions and potential for plastic responses to global changes, we used a space-for-time substitution study, a neighbor removal experiment, and reciprocal transplant experiment. Earlier snowmelt was associated with longer phenological development periods, an increased likelihood of herbivory and fungal damage, fewer stems and no increase in end-of-season wood reserve carbohydrates. Furthermore, while early snowmelt was associated with an increased proportion of flowering stems, the number of fruiting stems was not, as fruit set decreased significantly with earlier snowmelt. Warmer temperatures at lower elevations were associated with decreases in stem number and wood low-molecular weight sugars, and increases in proportion of stems fruiting. In the reciprocal transplant experiment, S. herbacea generally started to grow earlier, but had a longer development time and produced smaller leaves on ridges relative to snowbeds. The phenological changes did not influence clonal or sexual reproduction, but smaller leaves in early-snowmelt sites were associated with reduced sexual reproduction, a potentially maladaptive response of leaf plasticity. Clonal and sexual reproduction generally showed no response to changes in snowmelt timing. Moreover, we found no home site advantage in terms of sexual and clonal reproduction. Leaf damage probability depended on snowmelt timing and thus exposure period, but it had no short-term effect on fitness traits. In the neighbor removal study, the majority of S. herbacea traits were controlled primarily by snowmelt timing. However, neighbour removal directly reduced the number of days required for fruit production relative to control shrubs; however, it also increased the likelihood of leaf tissue herbivory. Effects of neighbour removal also changed along the environmental gradients, with neighbour removal leading to reduced leaf size on earlier snowmelt sites, and increased fungal damage with increasing elevation. We conclude that Salix herbacea exhibits strong reductions in performance under earlier snowmelt, with few benefits of warming temperatures. Further, plasticity in leaf traits may lead to fitness reductions under earlier snowmelt. With accelerated spring snowmelt, environmental stress will likely increase due to increasing exposure to cold temperatures and damage agents, which reduce the leaf crops and flowering probability in the following summers. However, detrimental effects of early snowmelt may be at least partly mediated by facilitative interactions by neighbours. Under climate change, we may begin to see reductions in clonal and sexual reproduction, leading to fitness declines in S. herbacea, which in turn may reduce persistence of populations in arctic and alpine ecosystems, particularly those growing on current early exposure microhabitats as spring snowmelt accelerates. The results of this thesis suggest that earlier spring snowmelt timing may represent one of the critical global change drivers reducing dwarf shrub performance in arctic and alpine tundra ecosystems

Early warning scores generated in developed healthcare settings are not sufficient at predicting early mortality in Blantyre, Malawi : a prospective cohort study

Early warning scores (EWS) are widely used in well-resourced healthcare settings to identify patients at risk of mortality. The Modified Early Warning Score (MEWS) is a well-known EWS used comprehensively in the United Kingdom. The HOTEL score (Hypotension, Oxygen saturation, Temperature, ECG abnormality, Loss of independence) was developed and tested in a European cohort; however, its validity is unknown in resource limited settings. This study compared the performance of both scores and suggested modifications to enhance accuracy

Book reviews

Teaching/Communication/Extension/Profession,

Forest expansion in abandoned agricultural lands has limited effect to offset carbon emissions from Central-North Spain

Producción CientíficaWe assessed the process of carbon (C) accumulation as a consequence of forest expansion in abandoned agricultural lands over the period 1977–2017 in a vast (9.4 million ha) area of Mediterranean continental environment in Central-North Spain. We achieved this objective, through obtaining AGC and BGC estimations based on direct field measurements taken in 30 plots (25 m × 25 m), and extrapolating to the landscape using Synthetic Aperture Radar (SAR) satellite data from 2018. Using aerial photographs and forest maps, we found that 145,193 ha of agricultural land in 1957 (1.54% of the study regions’ total area) has since then regenerated naturally to forests and woodlands. Although mean AGC and BGC densities were modest (i.e. 18.04 and 6.78 Mg C ha−1), they reached relatively large maximum values (i.e. 60 and 21 Mg C ha−1). The BGC stock was also very large, representing 37.3% of the total C stock (10 Tg) accumulated. However, we detected a mean annual C sink of 0.25 Tg C·year−1 which barely offset 1.22% of the total regional CO2 emissions. Our findings point to a smaller sequestration potential under Mediterranean continental than under temperate-cold conditions. Nonetheless, the area affected by this process could be larger than detected and many of the recovering lands might have not still reached their C uptake peak. If such lands are to be used to store C, we strongly advocate for the application of active forest management measures to increase their CO2 sequestration potential.European Union’s Horizon 2020 research and innovation program. grant agreement no. 799885.Publicación en abierto financiada por el Consorcio de Bibliotecas Universitarias de Castilla y León (BUCLE), con cargo al Programa Operativo 2014ES16RFOP009 FEDER 2014-2020 DE CASTILLA Y LEÓN, Actuación:20007-CL - Apoyo Consorcio BUCL

The Environmental Context and Function of Burnt-Mounds : New Studies of Irish Fulachtaí Fiadh

The authors acknowledge funding from The Leverhulme Trust (F/00144/AI) and assistance from a large number of individuals including; Margaret Gowen (access to sites and assistance throughout),A. Ames, H, Essex (pollen processing), S. Rouillard & R. Smith (illustrations), C. McDermott, S. Bergerbrandt, all the staff of Margaret Gowen & Co. Ltd, TVAS Ireland and CRDS. Excavation works and some post-excavation analysis was paid for my Bord Gáis and the National Roads Authority (now Transport Infrastructure Ireland). Thanks also to David Smith for access to the Maureen Girling collection and assistance with identifications.Peer reviewedPostprintPostprin

A systematic review of vestibular stimulation in post-stroke visual neglect

Unilateral visual neglect is a condition that negatively impacts the lives of many stroke survivors. Studies have investigated different forms of vestibular stimulation as a potential therapy, but evidence is yet to be systematically reviewed. We therefore reviewed the effects of vestibular stimulation on outcomes of neglect and activities of daily living (ADL) for people with visual neglect. We searched relevant databases up until September 2022. Eligible articles included any form of vestibular stimulation, study design, or control condition. Included participants were 18 years or older, presenting with neglect following a haemorrhagic or ischaemic stroke. Relevant outcomes were clinically validated measures of neglect and ADL. Cochrane risk of bias tools were used to assess study quality. Meta-analyses and narrative methods were used to synthesize the data. Our search returned 17 relevant studies comprising 180 participants. Meta-analyses showed no difference between galvanic vestibular stimulation and sham conditions on outcomes, whereas caloric vestibular stimulation led to improvement compared to pre-stimulation scores. Narrative syntheses showed mixed results. Clinical and methodological heterogeneity was found both within and between studies. Overall, results were inconsistent regarding the effects of vestibular stimulation as a treatment for neglect. Further trials are warranted but require more careful methodological planning

Operationalising the Recovery College model with people living with dementia: a realist review

© 2024 The Author(s). Published by Informa UK Limited, trading as Taylor & Francis Group. This is an open access article distributed under the terms of the Creative Commons Attribution License (CC BY), https://creativecommons.org/licenses/by/4.0/Objectives Post-diagnostic support is a significant factor for facilitating personal recovery following a diagnosis of dementia, but access is often inconsistent and insufficient. Recovery Colleges offer peer-led, co-produced courses that can support people to have meaningful lives and have been adapted for use in the context of dementia. A realist review was conducted to understand the application and sustainability of Recovery College dementia courses. Methods An iterative, five-step process combined literature published to 2023 with knowledge from stakeholders with lived and professional experience of dementia involved with Recovery College dementia courses (PROSPERO registration CRD42021293687). Results Thirty-five documents and discussions with 19 stakeholders were used to build the initial programme theory comprising of 24 context-mechanism-outcome configurations. Reoccurring factors included: attending to aspects of co-production and course delivery to ensure they promoted inclusion and were not compromised by organisational pressures; how stigma impacted access to course opportunities; and embedding personal recovery principles throughout course development to be relevant for people living with dementia and those who support them. Conclusion People struggling to reconcile their future alongside dementia need practical and emotional support to access and benefit from Recovery College dementia courses, ways to achieve this will be explored through a realist evaluation.Peer reviewe

Systemic inflammation associates with and precedes cord atrophy in progressive multiple sclerosis

In preclinical models of multiple sclerosis, systemic inflammation has an impact on the compartmentalised inflammatory process within the central nervous system and results in axonal loss. It remains to be shown whether this is the case in humans, specifically whether systemic inflammation contributes to spinal cord or brain atrophy in multiple sclerosis. Hence, an observational longitudinal study was conducted to delineate the relationship between systemic inflammation and atrophy using magnetic resonance imaging: the SIMS (Systemic Inflammation in Multiple Sclerosis) study. Systemic inflammation and progression were assessed in people with progressive multiple sclerosis (n = 50) over two and a half years. Eligibility criteria included: (1) primary or secondary progressive multiple sclerosis, (2) age ≤70, and (3) Expanded Disability Status Scale ≤6.5. First morning urine was collected weekly to quantify systemic inflammation by measuring the urinary neopterin-to-creatinine ratio using a validated ultra-performance liquid chromatography mass spectrometry technique. The urinary neopterin-to-creatinine ratio temporal profile was characterised by short-term responses overlaid on a background level of inflammation, so these two distinct processes were considered as separate variables: background inflammation and inflammatory response. In preclinical models, the effects of a systemic inflammatory challenge on tissue injury depended on prior exposure to inflammation. Participants underwent MRI at the start and end of the study, to measure cervical spinal cord and brain atrophy. Brain and cervical cord atrophy occurred on the study, but the most striking change was seen in the cervical spinal cord, in keeping with the corticospinal tract involvement that is typical of progressive disease. Systemic inflammation predicted cervical cord atrophy. An association with brain atrophy was not observed in this cohort. A time lag between systemic inflammation and cord atrophy was evident, suggesting but not proving causation. The association of the inflammatory response with cord atrophy depended on the level of background inflammation, in keeping with experimental data in preclinical models. A higher inflammatory response was associated with accelerated cord atrophy in the presence of background systemic inflammation below the median for the study population. Higher background inflammation, while associated with cervical cord atrophy itself, subdued the association of the inflammatory response with cord atrophy. Findings were robust to sensitivity analyses adjusting for potential confounders and excluding cases with new lesion formation. In conclusion, systemic inflammation associates with, and precedes, multiple sclerosis progression. Further work is needed to prove causation since targeting systemic inflammation may offer novel treatment strategies for slowing neurodegeneration in multiple sclerosis

A New Field Protocol for Monitoring Forest Degradation

Forest degradation leads to the gradual reduction of forest carbon stocks, function, and biodiversity following anthropogenic disturbance. Whilst tropical degradation is a widespread problem, it is currently very under-studied and its magnitude and extent are largely unknown. This is due, at least in part, to the lack of developed and tested methods for monitoring degradation. Due to the relatively subtle and ongoing changes associated with degradation, which can include the removal of small trees for fuelwood or understory clearance for agricultural production, it is very hard to detect using Earth Observation. Furthermore, degrading activities are normally spatially heterogeneous and stochastic, and therefore conventional forest inventory plots distributed across a landscape do not act as suitable indicators: at best only a small proportion of plots (often zero) will actually be degraded in a landscape undergoing active degradation. This problem is compounded because the metal tree tags used in permanent forest inventory plots likely deter tree clearance, biasing inventories toward under-reporting change. We have therefore developed a new forest plot protocol designed to monitor forest degradation. This involves a plot that can be set up quickly, so a large number can be established across a landscape, and easily remeasured, even though it does not use tree tags or other obvious markers. We present data from a demonstration plot network set up in Jalisco, Mexico, which were measured twice between 2017 and 2018. The protocol was successful, with one plot detecting degradation under our definition (losing greater than 10% AGB but remaining forest), and a further plot being deforested for Avocado (Persea americana) production. Live AGB ranged from 8.4 Mg ha–1 to 140.8 Mg ha–1 in Census 1, and from 0 Mg ha–1 to 144.2 Mg ha–1 Census 2, with four of ten plots losing AGB, and the remainder staying stable or showing slight increases. We suggest this protocol has great potential for underpinning appropriate forest plot networks for degradation monitoring, potentially in combination with Earth Observation analysis, but also in isolation