Consistent patterns of common species across tropical tree communities.

Trees structure the Earth's most biodiverse ecosystem, tropical forests. The vast number of tree species presents a formidable challenge to understanding these forests, including their response to environmental change, as very little is known about most tropical tree species. A focus on the common species may circumvent this challenge. Here we investigate abundance patterns of common tree species using inventory data on 1,003,805 trees with trunk diameters of at least 10 cm across 1,568 locations1-6 in closed-canopy, structurally intact old-growth tropical forests in Africa, Amazonia and Southeast Asia. We estimate that 2.2%, 2.2% and 2.3% of species comprise 50% of the tropical trees in these regions, respectively. Extrapolating across all closed-canopy tropical forests, we estimate that just 1,053 species comprise half of Earth's 800 billion tropical trees with trunk diameters of at least 10 cm. Despite differing biogeographic, climatic and anthropogenic histories7, we find notably consistent patterns of common species and species abundance distributions across the continents. This suggests that fundamental mechanisms of tree community assembly may apply to all tropical forests. Resampling analyses show that the most common species are likely to belong to a manageable list of known species, enabling targeted efforts to understand their ecology. Although they do not detract from the importance of rare species, our results open new opportunities to understand the world's most diverse forests, including modelling their response to environmental change, by focusing on the common species that constitute the majority of their trees.

High aboveground carbon stock of African tropical montane forests.

Tropical forests store 40-50 per cent of terrestrial vegetation carbon1. However, spatial variations in aboveground live tree biomass carbon (AGC) stocks remain poorly understood, in particular in tropical montane forests2. Owing to climatic and soil changes with increasing elevation3, AGC stocks are lower in tropical montane forests compared with lowland forests2. Here we assemble and analyse a dataset of structurally intact old-growth forests (AfriMont) spanning 44 montane sites in 12 African countries. We find that montane sites in the AfriMont plot network have a mean AGC stock of 149.4 megagrams of carbon per hectare (95% confidence interval 137.1-164.2), which is comparable to lowland forests in the African Tropical Rainforest Observation Network4 and about 70 per cent and 32 per cent higher than averages from plot networks in montane2,5,6 and lowland7 forests in the Neotropics, respectively. Notably, our results are two-thirds higher than the Intergovernmental Panel on Climate Change default values for these forests in Africa8. We find that the low stem density and high abundance of large trees of African lowland forests4 is mirrored in the montane forests sampled. This carbon store is endangered: we estimate that 0.8 million hectares of old-growth African montane forest have been lost since 2000. We provide country-specific montane forest AGC stock estimates modelled from our plot network to help to guide forest conservation and reforestation interventions. Our findings highlight the need for conserving these biodiverse9,10 and carbon-rich ecosystems.

Asynchronous carbon sink saturation in African and Amazonian tropical forests.

Structurally intact tropical forests sequestered about half of the global terrestrial carbon uptake over the 1990s and early 2000s, removing about 15 per cent of anthropogenic carbon dioxide emissions1-3. Climate-driven vegetation models typically predict that this tropical forest 'carbon sink' will continue for decades4,5. Here we assess trends in the carbon sink using 244 structurally intact African tropical forests spanning 11 countries, compare them with 321 published plots from Amazonia and investigate the underlying drivers of the trends. The carbon sink in live aboveground biomass in intact African tropical forests has been stable for the three decades to 2015, at 0.66 tonnes of carbon per hectare per year (95 per cent confidence interval 0.53-0.79), in contrast to the long-term decline in Amazonian forests6. Therefore the carbon sink responses of Earth's two largest expanses of tropical forest have diverged. The difference is largely driven by carbon losses from tree mortality, with no detectable multi-decadal trend in Africa and a long-term increase in Amazonia. Both continents show increasing tree growth, consistent with the expected net effect of rising atmospheric carbon dioxide and air temperature7-9. Despite the past stability of the African carbon sink, our most intensively monitored plots suggest a post-2010 increase in carbon losses, delayed compared to Amazonia, indicating asynchronous carbon sink saturation on the two continents. A statistical model including carbon dioxide, temperature, drought and forest dynamics accounts for the observed trends and indicates a long-term future decline in the African sink, whereas the Amazonian sink continues to weaken rapidly. Overall, the uptake of carbon into Earth's intact tropical forests peaked in the 1990s. Given that the global terrestrial carbon sink is increasing in size, independent observations indicating greater recent carbon uptake into the Northern Hemisphere landmass10 reinforce our conclusion that the intact tropical forest carbon sink has already peaked. This saturation and ongoing decline of the tropical forest carbon sink has consequences for policies intended to stabilize Earth's climate.

Global dominance of lianas over trees is driven by forest disturbance, climate and topography.

Growing evidence suggests that liana competition with trees is threatening the global carbon sink by slowing the recovery of forests following disturbance. A recent theory based on local and regional evidence further proposes that the competitive success of lianas over trees is driven by interactions between forest disturbance and climate. We present the first global assessment of liana-tree relative performance in response to forest disturbance and climate drivers. Using an unprecedented dataset, we analysed 651 vegetation samples representing 26,538 lianas and 82,802 trees from 556 unique locations worldwide, derived from 83 publications. Results show that lianas perform better relative to trees (increasing liana-to-tree ratio) when forests are disturbed, under warmer temperatures and lower precipitation and towards the tropical lowlands. We also found that lianas can be a critical factor hindering forest recovery in disturbed forests experiencing liana-favourable climates, as chronosequence data show that high competitive success of lianas over trees can persist for decades following disturbances, especially when the annual mean temperature exceeds 27.8°C, precipitation is less than 1614 mm and climatic water deficit is more than 829 mm. These findings reveal that degraded tropical forests with environmental conditions favouring lianas are disproportionately more vulnerable to liana dominance and thus can potentially stall succession, with important implications for the global carbon sink, and hence should be the highest priority to consider for restoration management.

Des preuves de plus en plus nombreuses suggèrent que la competition entre lianes et les arbres menace le puits de carbone mondial en ralentissant la récupération des forêts après une perturbation. Une théorie récente, fondée sur des observations locales et régionales, propose en outre que le succès compétitif des lianes sur les arbres est dû aux interactions entre la perturbation forestière et le climat. Nous présentons la première évaluation mondiale de la performance relative des lianes par rapport aux arbres en réponse aux perturbations forestières et aux facteurs climatiques. En utilisant un ensemble de données sans précédent, nous avons analysé 651 échantillons de végétation représentant 26,538 lianes et 82,802 arbres, issus de 556 emplacements uniques dans le monde entier, tirés de 83 publications. Les résultats montrent que les lianes ont de meilleure performances par rapport aux arbres (augmentation du ratio liane-arbre) lorsque les forêts sont perturbées, sous des zones chaudes aves précipitations faibles, et vers les basses altitudes tropicales. Nous avons également constaté que les lianes peuvent être un facteur critique entravant la récupération des forêts dans les forêts perturbées connaissant des climats favorables aux lianes, car les données de chronoséquence montrent que le succès compétitif élevé des lianes sur les arbres peut persister pendant des décennies après les perturbations, surtout lorsque la température annuelle moyenne dépasse 27.8°C, que les précipitations sont inférieures à 1614 mm et que le déficit hydrique climatique est supérieur à 829 mm. Ces découvertes révèlent que les forêts tropicales dégradées avec des conditions environnementales favorables aux lianes sont disproportionnellement plus vulnérables à la dominance des lianes, et peuvent ainsi potentiellement entraver la succession, avec d'importantes implications pour le puits de carbone mondial et devraient donc être la plus haute priorité à considérer pour la gestion de la restauration.

Resistance of African tropical forests to an extreme climate anomaly.

The responses of tropical forests to environmental change are critical uncertainties in predicting the future impacts of climate change. The positive phase of the 2015-2016 El Niño Southern Oscillation resulted in unprecedented heat and low precipitation in the tropics with substantial impacts on the global carbon cycle. The role of African tropical forests is uncertain as their responses to short-term drought and temperature anomalies have yet to be determined using on-the-ground measurements. African tropical forests may be particularly sensitive because they exist in relatively dry conditions compared with Amazonian or Asian forests, or they may be more resistant because of an abundance of drought-adapted species. Here, we report responses of structurally intact old-growth lowland tropical forests inventoried within the African Tropical Rainforest Observatory Network (AfriTRON). We use 100 long-term inventory plots from six countries each measured at least twice prior to and once following the 2015-2016 El Niño event. These plots experienced the highest temperatures and driest conditions on record. The record temperature did not significantly reduce carbon gains from tree growth or significantly increase carbon losses from tree mortality, but the record drought did significantly decrease net carbon uptake. Overall, the long-term biomass increase of these forests was reduced due to the El Niño event, but these plots remained a live biomass carbon sink (0.51 ± 0.40 Mg C ha-1 y-1) despite extreme environmental conditions. Our analyses, while limited to African tropical forests, suggest they may be more resistant to climatic extremes than Amazonian and Asian forests.

Life satisfaction 18 months and 10 years following spinal cord injury: results from a New Zealand prospective cohort study.

PURPOSE: To examine the life satisfaction outcomes after spinal cord injury (SCI) and to identify the factors associated with life satisfaction at 18 months and 10 years post-SCI in New Zealand (NZ). METHODS: Adults (16-64 years) were recruited between 2007 and 2009 from NZ's two spinal units following first admission for SCI. Interviews at 6 months, 18 months, and 10 years post-SCI examined demographic, physical, psychosocial, economic, and environmental characteristics. Multivariable regression models were used to identify predictors of life satisfaction at each timepoint. RESULTS: Overall, 118 people participated at 6 months, 103 at 18 months, and 63 at 10 years post-SCI. Pre-SCI, 90% of participants were satisfied with life, 67% were satisfied at 18 months, and 78% at 10 years. At 18 months post-SCI, participants who reported: never or sometimes using a wheelchair, no problems with self-care, no problems with anxiety or depression, no/lesser disability, or fewer secondary health conditions (SHCs) at 6 months post-SCI were more likely to be satisfied (p < 0.05), compared to those without these characteristics. Participants who experienced considerable disability at 6 months post-SCI were 22% less likely to be satisfied 10 years post-SCI compared to those experiencing no/lesser disability (p = 0.028). CONCLUSIONS: A higher proportion of participants were satisfied at both 18 months and 10 years post-SCI than not satisfied. To improve the likelihood of satisfaction with life, increased focus on reducing disability and providing supports for those using wheelchairs, experiencing anxiety/depression or problems with self-care, and effects of SHCs are promising for future potential interventions.

The LOCalizer Radiofrequency Identification System: An Effective New Technology for Localizing Non-Palpable Breast Lesions for Surgery.

Background. Breast screening has decreased morbidity and mortality due to detection of early, non-palpable breast cancers. One of the challenges of performing breast-conserving surgery on non-palpable breast tumours is accurate localization of the cancer. We aimed to perform a feasibility study to examine the outcomes associated with the introduction of a novel radiofrequency identification system (RFID) called LOCalizer as an alternative to traditional wire-guided localization. Methods. Data were prospectively collected on all patients undergoing breast-conserving surgery using the LOCalizer RFID system in a regional cancer centre between July 2019 and March 2020. Patients had a RFID tag placed preoperatively and underwent surgical removal of the tag with the index lesion guided by a handheld LOCalizer probe. The primary aim was successful placement and retrieval of the RFID tag. Re-excision rates, specimen size, specimen weight, cancer subtype and complication rate were all recorded. Results. Sixty-nine patients aged between 50 and 69 years had a LOCalizer tag inserted between July 2019 and March 2020. Of these, 6 (8.7%) were diagnostic and 63 (91.3%) were therapeutic. There was no migration of RFID tags, and all tags were retrieved with the index lesion. The overall re-excision of margin rate was 17.4% (12/69). All re-excision of margins was due to positive radial margins. The overall complication rate was 1.4% with one grade 1 Clavien-Dindo morbidity. Conclusion. The LOCalizer RFID is an effective and safe wire-free localization method for non-palpable breast lesions.

Species interactions modulate the response of saltmarsh plants to flooding.

BACKGROUND AND AIMS: The vegetation that grows on coastal wetlands is important for ecosystem functioning, a role mediated by plant traits. These traits can be affected by environmental stressors and by the competitive environment the plant experiences. The relative importance of these influences on different traits is poorly understood and, despite theoretical expectations for how factors may interact, empirical data are conflicting. Our aims are to determine the effect of flooding, species composition and their interaction on plant functional traits, and assess the role of biodiversity and species composition in driving community-level responses to flooding. METHODS: We conducted a factorial glasshouse experiment assessing the effects of species composition (all combinations of three saltmarsh species, Aster tripolium, Plantago maritima and Triglochin maritima) and flooding (immersion of roots) on a suite of functional traits. We also related biomass in mixed species pots to that expected from monocultures to assess how species interactions affect community-level biomass. KEY RESULTS: Species composition frequently interacted with flooding to influence functional traits and community-level properties. However, there was also considerable intraspecific variability in traits within each treatment. Generally, effects of flooding were more pronounced for below-ground than above-ground biomass, while composition affected above-ground biomass more than below-ground biomass. We found both negative and positive interactions between species (indicated by differences in above- and below-ground biomass from expectations under monoculture), meaning that composition was an important determinate of community function. CONCLUSIONS: While the effect of flooding alone on traits was relatively weak, it interacted with species composition to modify the response of both individual plants and communities. Our results suggest that responses to increased flooding will be complex and depend on neighbourhood species interactions. Furthermore, intraspecific trait variability is a potential resource that may dampen the effects of changes in flooding regime.

Evaluation of radiographs for the detection of sublumbar lymphadenopathy in dogs.

The purpose of this study was to evaluate radiographs for the detection of sublumbar lymph node (SLN) enlargement. Ultrasound was used to determine SLN size. Twenty-two dogs with anal gland adenocarcinoma or lymphoma were prospectively included, with 16/22 having SLN enlargement on ultrasound. Twenty-one dogs without enlargement were retrospectively included as controls. Three blinded observers evaluated 43 right lateral abdominal radiographs for the presence of SLN enlargement. Sensitivity and specificity of radiographs for the detection of SLN enlargement were 81%/70%, 94%/81%, and 75%/100% for a general practitioner, imaging resident, and radiologist, respectively. Ventral displacement of the colon, a soft tissue opacity in the caudal retroperitoneal space and loss of conspicuity of the ventral margin of the iliopsoas muscle were radiographic findings significantly associated with identification (P-values < 0.05). Markedly enlarged SLNs (> 21.5 mm) were consistently detected radiographically by observers with specialist imaging training. Key clinical message: Radiographic visualization should raise suspicion of neoplastic infiltration of SLN but lack of visualization does not exclude mild to moderate enlargement. Additional imaging such as ultrasound or computed tomography remains important to confirm or exclude sublumbar lymphadenopathy.

Évaluation de radiographies pour la détection de lymphadénopathie sub-lombaire chez des chiens. Le but de la présente étude était d'évaluer des radiographies pour détecter l'augmentation de taille des ganglions sub-lombaires (SLN). L'échographie fut utilisée pour déterminer la taille des SLN. Vingt-deux chiens avec un adénocarcinome des glandes anales ou un lymphome furent inclus prospectivement, avec 16/22 ayant des SLN augmentés lors de l'échographie. Vingt-et-un chiens sans augmentation de taille furent inclus rétrospectivement comme témoins. Trois observateurs ont évalué à l'aveugle 43 radiographies abdominales latérales droites pour la présence d'augmentation des SLN. La sensibilité et la spécificité des radiographies pour la détection d'augmentation des SLN étaient de 81 %/70 %, 94 %/81 % et 75 %/100 % pour un praticien généraliste, un résident en imagerie et un radiologiste, respectivement. Un déplacement ventral du côlon, une opacité des tissus mous dans l'espace rétropéritonéal caudal et une perte de visibilité de la bordure ventrale du muscle iliopsoas furent des trouvailles radiographiques associées significativement avec l'identification (P < 0,05). Des SLN avec une forte augmentation de taille (> 21,5 mm) étaient constamment détectés radiographiquement par des observateurs avec une formation spécialisée en imagerie.Message clinique clé:La visualisation radiographique devrait soulever des soupçons d'infiltration néoplasique des SNL mais le manque de visualisation n'exclu pas une augmentation de taille de légère à modérée. Des analyses en imagerie additionnelles, telles que l'échographie ou la tomodensitométrie, demeurent importantes pour confirmer ou exclure une lymphadénopathie sub-lombaire.(Traduit par Dr Serge Messier).

Estimating aboveground net biomass change for tropical and subtropical forests: Refinement of IPCC default rates using forest plot data.

As countries advance in greenhouse gas (GHG) accounting for climate change mitigation, consistent estimates of aboveground net biomass change (∆AGB) are needed. Countries with limited forest monitoring capabilities in the tropics and subtropics rely on IPCC 2006 default ∆AGB rates, which are values per ecological zone, per continent. Similarly, research into forest biomass change at a large scale also makes use of these rates. IPCC 2006 default rates come from a handful of studies, provide no uncertainty indications and do not distinguish between older secondary forests and old-growth forests. As part of the 2019 Refinement to the 2006 IPCC Guidelines for National Greenhouse Gas Inventories, we incorporate ∆AGB data available from 2006 onwards, comprising 176 chronosequences in secondary forests and 536 permanent plots in old-growth and managed/logged forests located in 42 countries in Africa, North and South America and Asia. We generated ∆AGB rate estimates for younger secondary forests (≤20 years), older secondary forests (>20 years and up to 100 years) and old-growth forests, and accounted for uncertainties in our estimates. In tropical rainforests, for which data availability was the highest, our ∆AGB rate estimates ranged from 3.4 (Asia) to 7.6 (Africa) Mg ha-1  year-1 in younger secondary forests, from 2.3 (North and South America) to 3.5 (Africa) Mg ha-1  year-1 in older secondary forests, and 0.7 (Asia) to 1.3 (Africa) Mg ha-1  year-1 in old-growth forests. We provide a rigorous and traceable refinement of the IPCC 2006 default rates in tropical and subtropical ecological zones, and identify which areas require more research on ∆AGB. In this respect, this study should be considered as an important step towards quantifying the role of tropical and subtropical forests as carbon sinks with higher accuracy; our new rates can be used for large-scale GHG accounting by governmental bodies, nongovernmental organizations and in scientific research.

Compositional response of Amazon forests to climate change.

Most of the planet's diversity is concentrated in the tropics, which includes many regions undergoing rapid climate change. Yet, while climate-induced biodiversity changes are widely documented elsewhere, few studies have addressed this issue for lowland tropical ecosystems. Here we investigate whether the floristic and functional composition of intact lowland Amazonian forests have been changing by evaluating records from 106 long-term inventory plots spanning 30 years. We analyse three traits that have been hypothesized to respond to different environmental drivers (increase in moisture stress and atmospheric CO2 concentrations): maximum tree size, biogeographic water-deficit affiliation and wood density. Tree communities have become increasingly dominated by large-statured taxa, but to date there has been no detectable change in mean wood density or water deficit affiliation at the community level, despite most forest plots having experienced an intensification of the dry season. However, among newly recruited trees, dry-affiliated genera have become more abundant, while the mortality of wet-affiliated genera has increased in those plots where the dry season has intensified most. Thus, a slow shift to a more dry-affiliated Amazonia is underway, with changes in compositional dynamics (recruits and mortality) consistent with climate-change drivers, but yet to significantly impact whole-community composition. The Amazon observational record suggests that the increase in atmospheric CO2 is driving a shift within tree communities to large-statured species and that climate changes to date will impact forest composition, but long generation times of tropical trees mean that biodiversity change is lagging behind climate change.

Differences in leaf thermoregulation and water use strategies between three co-occurring Atlantic forest tree species.

Given anticipated climate changes, it is crucial to understand controls on leaf temperatures including variation between species in diverse ecosystems. In the first study of leaf energy balance in tropical montane forests, we observed current leaf temperature patterns on 3 tree species in the Atlantic forest, Brazil, over a 10-day period and assessed whether and why patterns may vary among species. We found large leaf-to-air temperature differences (maximum 18.3 °C) and high leaf temperatures (over 35 °C) despite much lower air temperatures (maximum 22 °C). Leaf-to-air temperature differences were influenced strongly by radiation, whereas leaf temperatures were also influenced by air temperature. Leaf energy balance modelling informed by our measurements showed that observed differences in leaf temperature between 2 species were due to variation in leaf width and stomatal conductance. The results suggest a trade-off between water use and leaf thermoregulation; Miconia cabussu has more conservative water use compared with Alchornea triplinervia due to lower transpiration under high vapour pressure deficit, with the consequence of higher leaf temperatures under thermal stress conditions. We highlight the importance of leaf functional traits for leaf thermoregulation and also note that the high radiation levels that occur in montane forests may exacerbate the threat from increasing air temperatures.

Encapsulation of Hydrophilic and Hydrophobic Peptides into Hollow Mesoporous Silica Nanoparticles for Enhancement of Antitumor Immune Response.

Codelivery of combinational antigenic peptides and adjuvant to antigen presenting cells is expected to amplify tumor specific T lymphocytes immune responses while minimizing the possibility of tumor escaping and reducing immune tolerance to single antigenic peptide. However, the varied hydrophobicities of these multivariant derived short antigenic peptides limit their codelivery efficiency in conventional delivery systems. Here, a facile yet effective route is presented to generate monodisperse and stable hollow mesoporous silica nanoparticles (HMSNs) for codelivering of HGP10025-33 and TRP2180-188 , two melanoma-derived peptides with varied hydrophobicities. The HMSNs with large pore size can improve the encapsulation efficiency of both HGP100 and TRP2 after NH2 modification on the inner hollow core and COOH modification in the porous channels. HGP100 and TRP2 loaded HMSNs (HT@HMSNs) are further enveloped within monophosphoryl lipid A adjuvant entrapped lipid bilayer (HTM@HMLBs), for improved stability/biocompatibility and codelivery efficiency of multiple peptides, adjuvant, and enhanced antitumor immune responses. HTM@HMLBs increase uptake by dendritic cells (DCs) and stimulate DCs maturation efficiently, which further induce the activation of both tumor specific CD8+ and CD4+ T lymphocytes. Moreover, HTM@HMLBs can significantly inhibit tumor growth and lung metastasis in murine melanoma models with good safety profiles. HMSNs enveloped with lipid bilayers (HMLBs) are believed to be a promising platform for codelivery of multiple peptides, adjuvant, and enhancement of antitumor efficacy of conventional vaccinations.

Angiographic anatomy of the extracranial and intracranial portions of the internal carotid arteries in donkeys.

BACKGROUND: In horses, the extracranial and intracranial pathway of the internal carotid artery has been described. The extracranial pathway of the internal carotid artery begins at the carotid termination and runs on the dorsal surface of the medial compartment of the guttural pouch. Thereafter the internal carotid artery passes through the foramen lacerum to continue intracranially, forming part of the rostrolateral quadrants of the cerebral arterial circle (Circle of Willis). The objectives of this study were to define and record the anatomy of the carotid arterial tree and the internal carotid artery in donkeys using angiographic techniques. This is a prospective descriptive study on 26 cadaveric donkeys. METHODS: Twenty six donkey cadavers of mixed, age, sex and use presented for reasons unrelated to disease of the guttural pouch were subjected to carotid and cerebral angiography using rotational angiography. Rotational angiographic and 3 dimensional multiplanar reconstructive (3D-MPR) findings were verified with an arterial latex casting technique followed by dissection and photography. RESULTS: The following variations of the carotid arterial tree were identified: [1] the internal carotid and occipital arteries shared a common trunk, [2] the linguofacial trunk originated from the common carotid artery causing the common carotid artery to terminate as four branches, [3] the external carotid artery was reduced in length before giving rise to the linguofacial trunk, mimicking the appearance of the common carotid artery terminating in four branches, [4] the internal carotid artery originated at a more caudal position from the common carotid artery termination. CONCLUSION: Veterinarians should be aware that considerable variation exists in the carotid arterial tree of donkeys and that this variation may differ markedly from that described in the horse.

Computed tomography measurements of the lesser metatarsal heads: Anatomic considerations for surgeons performing distal metatarsal osteotomies.

BACKGROUND: The purpose of the current study was to provide a standardized, anatomical description of the lesser metatarsals to assist surgeons when planning distal metatarsal surgery and fixation. METHODS: Eighty CT scans were included for assessment, based on a priori power analysis. Patient age was a mean 52.7±16.6 years (24-83). Metatarsals two through five were assessed in all patients. Three independent observers completed measurements for all metatarsals. Three measurements were made on all metatarsals, including a vertical height and metatarsal head and neck measurements. Statistical analysis was performed (alpha value 0.05). Inter-observer reliability was assessed for all measurements and intra-class correlation (ICC) reported. RESULTS: A sequential decrease in metatarsal measurements was noted from the second to the fifth metatarsal. A mean vertical height measurement of 16.1±1.4mm (range, 13.4-19.4) was recorded for the second metatarsal, decreasing 13.0±1.1mm (range, 10.3-16.1) for fifth. There were no significant differences in metatarsal measurements based on gender in our study. Similar patient and metatarsal variability was seen head and neck measurements. Intraclass correlation coefficients (ICC) for metatarsal measurements were greater than 0.9 [95% CI; 0.936-0.991] correlation, denoting an 'excellent' interobserver reliability. CONCLUSION: This study provides a baseline anatomical description of the distal metatarsals. These findings, including the variation found between patients and between metatarsal two through five, are relevant to surgeons planning and performing distal metatarsal osteotomies.

Grassland responses to increased rainfall depend on the timescale of forcing.

Forecasting impacts of future climate change is an important challenge to biologists, both for understanding the consequences of different emissions trajectories and for developing adaptation measures that will minimize biodiversity loss. Existing variation provides a window into the effects of climate on species and ecosystems, but in many places does not encompass the levels or timeframes of forcing expected under directional climatic change. Experiments help us to fill in these uncertainties, simulating directional shifts to examine outcomes of new levels and sustained changes in conditions. Here, we explore the translation between short-term responses to climate variability and longer-term trajectories that emerge under directional climatic change. In a decade-long experiment, we compare effects of short-term and long-term forcings across three trophic levels in grassland plots subjected to natural and experimental variation in precipitation. For some biological responses (plant productivity), responses to long-term extension of the rainy season were consistent with short-term responses, while for others (plant species richness, abundance of invertebrate herbivores and predators), there was pronounced divergence of long-term trajectories from short-term responses. These differences between biological responses mean that sustained directional changes in climate can restructure ecological relationships characterizing a system. Importantly, a positive relationship between plant diversity and productivity turned negative under one scenario of climate change, with a similar change in the relationship between plant productivity and consumer biomass. Inferences from experiments such as this form an important part of wider efforts to understand the complexities of climate change responses.

Evidence for the buffer effect operating in multiple species at a national scale.

A long-standing aim of ecologists is to understand the processes involved in regulating populations. One such mechanism is the buffer effect, where lower quality habitats are increasingly used as a species reaches higher population densities, with a resultant average reduction in fecundity and survival limiting population growth. Although the buffer effect has been demonstrated in populations of a number of species, a test of its importance in influencing population growth rates of multiple species across large spatial scales is lacking. Here, we use habitat-specific population trends for 85 bird species from long-term national monitoring data (the UK Breeding Bird Survey) to examine its generality. We find that both patterns of population change and changes in habitat preference are consistent with the predictions of the buffer effect, providing support for its widespread operation.

Angiographic Variation of the Internal Carotid Artery and its Branches in Horses.

OBJECTIVES: To record the angiographic anatomy of the equine internal carotid artery (ICA) using angiography techniques. STUDY DESIGN: In vitro descriptive study. SAMPLE POPULATION: Equine cadaver specimens (n = 50). METHODS: Head and neck specimens from horses of mixed breed, age, sex, and use without a history of guttural pouch disease had carotid and cerebral angiography using conventional (n = 7) and rotational angiography (43). Angiographic findings were verified by arterial latex casts. RESULTS: Variation in ICA anatomy was categorized into 4 groups: (1) the internal carotid and occipital arteries arising as a common trunk; (2) an aberrant branch of the extra-cranial ICA connected to the basilar artery; (3) an aberrant branch of the ICA ramifying into the surrounding tissue and not connected to any other vessels; and (4) an aberrant branch of the ICA giving rise to several smaller satellite branches, including connections to the caudal branch of the ipsilateral occipital artery. CONCLUSION: Rotational angiography is useful for identification of anatomic variation in the ICA that could be important in achieving vascular occlusion in the treatment of guttural pouch mycosis.

Magnetic resonance imaging contrast enhancement of extra-ocular muscles in dogs with no clinical evidence of orbital disease.

Enhancement of extra-ocular muscles has been reported in cases of orbital pathology in both veterinary and medical magnetic resonance imaging. We have also observed this finding in the absence of orbital disease. The purpose of this retrospective study was to describe extra-ocular muscle contrast enhancement characteristics in a group of dogs with no known orbital disease. Magnetic resonance images (MRI) from dogs with no clinical evidence of orbital disease and a reportedly normal MRI study were retrieved and reviewed. Contrast enhancement percentages of the medial, lateral, ventral, and dorsal rectus muscles were calculated based on signal-to-noise ratios that were in turn determined from hand-traced regions of interest in precontrast, immediate postcontrast and 10-min postcontrast scans. Comparison measurements were made in the pterygoid muscle. Contrast enhancement of the extra-ocular muscles was observed in all patients (median contrast enhancement percentage 45.0%) and was greater than that of pterygoid muscle (median contrast enhancement percentage 22.7%). Enhancement of the extra-ocular muscles persisted 10 min after contrast administration (median contrast enhancement percentage 43.4%). Findings indicated that MRI contrast enhancement of extra-ocular muscles is likely normal in dogs.

The impact of the COVID-19 pandemic on symptomatic breast cancer presentations in an Irish breast cancer unit: a retrospective cohort study.

BACKGROUND: The coronavirus-19 (COVID-19) pandemic caused delays in the diagnosis and management of breast cancer which may have affected disease presentation. The aim of this study was to compare rates of metastatic disease, tumour characteristics and management in breast cancer patients diagnosed before and after the onset of COVID-19. METHODS: A retrospective chart review was conducted on patients in a university teaching hospital who were diagnosed with invasive symptomatic breast cancer in 2019 (prepandemic control group) and in 2020, 2021, and 2022 (pandemic study groups). Rates of new metastatic presentations, tumour histopathological characteristics, operation type, and therapies administered were statistically compared. RESULTS: A total of 1416 patients were identified. There was a significant increase in new metastatic breast cancer presentations in 2022 compared to 2019 (14.0% vs 3.8%, p ≤ 0.001), with non-significant increases in 2020 and 2021. Rates of adjuvant radiotherapy increased in 2020 and decreased in 2022 compared to 2019, with no significant change in neoadjuvant or adjuvant chemotherapy rates. Rates of axillary surgery increased during 2020 and 2021. There was an increase in high-grade tumours and lymphovascular invasion (LVI), and less frequent oestrogen receptor (ER) positivity in pandemic groups. No significant change was noted in BCS to mastectomy ratios, overall nodal positivity rates, or median tumour size. CONCLUSION: Symptomatic breast cancers diagnosed since the onset of COVID-19 demonstrated an increase in new metastatic presentations and more aggressive histopathological characteristics when compared to a pre-pandemic control group. Rates of adjuvant radiotherapy and axillary surgery increased during the pandemic.