Evidence of thermophilization in Afromontane forests.

Thermophilization is the directional change in species community composition towards greater relative abundances of species associated with warmer environments. This process is well-documented in temperate and Neotropical plant communities, but it is uncertain whether this phenomenon occurs elsewhere in the tropics. Here we extend the search for thermophilization to equatorial Africa, where lower tree diversity compared to other tropical forest regions and different biogeographic history could affect community responses to climate change. Using re-census data from 17 forest plots in three mountain regions of Africa, we find a consistent pattern of thermophilization in tree communities. Mean rates of thermophilization were +0.0086 °C·y-1 in the Kigezi Highlands (Uganda), +0.0032 °C·y-1 in the Virunga Mountains (Rwanda-Uganda-Democratic Republic of the Congo) and +0.0023 °C·y-1 in the Udzungwa Mountains (Tanzania). Distinct from other forests, both recruitment and mortality were important drivers of thermophilzation in the African plots. The forests studied currently act as a carbon sink, but the consequences of further thermophilization are unclear.

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.

Patients' and doctors' views and experiences of the patient safety trajectory of breast cancer care.

INTRODUCTION: Successful breast cancer outcomes can be jeopardised by adverse events. Understanding and integrating patients' and doctors' perspectives into care trajectories could improve patient safety. This study assessed their views on, and experiences of, medical error and patient safety. METHODS: A cross-sectional, quantitative 20-40 item questionnaire for patients attending Cork University Hospital Cancer Centre and breast cancer doctors in the Republic of Ireland was developed. Domains included demographics, medical error experience, patient safety opinions and concerns. RESULTS: 184 patients and 116 doctors completed the survey. Of the doctors, 41.4% felt patient safety had deteriorated over the previous five years and 54.3% felt patient safety measures were inadequate compared to 13.0% and 27.7% of patients respectively. Of the 30 patients who experienced medical errors/negligence claims, 18 reported permanent or long-term physical and emotional effects. Forty-two of 48 (87.5%) doctors who experienced medical errors/negligence claims reported emotional health impacts. Almost half of doctors involved in negligence claims considered early retirement. Forty-four patients and 154 doctors didn't experience errors but reported their patient safety concerns. Doctors were more concerned about communication and administrative errors, staffing and organisational factors compared to patients. Multiple barriers to error reporting were highlighted. CONCLUSION: This is the first study to assess patients' and doctors' patient safety views and medical error/negligence claims experiences in breast cancer care in Ireland. Experience of medical error/negligence claims had long-lasting implications for both groups. Doctors were concerned about a multitude of errors and causative factors. Failure to embed these findings is a missed opportunity to improve safety.

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.

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.

Dealing with digital paralysis: Surviving a cyberattack in a National Cancer center.

INTRODUCTION: Cyberattacks represent a growing threat for healthcare delivery globally. We assess the impact and implications of a cyberattack on a cancer center in Ireland. METHODS: On May 14th 2021 (day 0) Cork University Hospital (CUH) Cancer Center was involved in the first national healthcare ransomware attack in Ireland. Contingency plans were only present in laboratory services who had previously experienced information technology (IT) failures. No hospital cyberattack emergency plan was in place. Departmental logs of activity for 120 days after the attack were reviewed and compared with historical activity records. Daily sample deficits (routine daily number of samples analyzed - number of samples analyzed during cyberattack) were calculated. Categorical variables are reported as median and range. Qualitative data were collected via reflective essays and interviews with key stakeholders from affected departments in CUH. RESULTS: On day 0, all IT systems were shut down. Radiotherapy (RT) treatment and cancer surgeries stopped, outpatient activity fell by 50%. hematology, biochemistry and radiology capacity fell by 90% (daily sample deficit (DSD) 2700 samples), 75% (DSD 2250 samples), and 90% (100% mammography/PET scan) respectively. Histopathology reporting times doubled (7 to 15 days). Radiotherapy (RT) was interrupted for 113 patients in CUH. The median treatment gap duration was six days for category 1 patients and 10 for the remaining patients. Partner organizations paused all IT links with CUH. Outsourcing of radiology and radiotherapy commenced, alternative communication networks and national conference calls in RT and Clinical Trials were established. By day 28 Email communication was restored. By day 210 reporting and data storage backlogs were cleared and over 2000 computers were checked/replaced. CONCLUSION: Cyberattacks have rapid, profound and protracted impacts. While laboratory and diagnostic deficits were readily quantified, the impact of disrupted/delayed care on patient outcomes is less readily quantifiable. Cyberawareness and cyberattack plans need to be embedded in healthcare. POLICY SUMMARY: Cyberattacks pose significant challenges for healthcare systems, impacting patient care, clinical outcomes, and staff wellbeing. This study provides a comprehensive review of the impact of the Conti ransomware attack on cancer services in Cork University Hospital (CUH), the first cyberattack on a national health service. Our study highlights the widespread disruption caused by a cyberattack including shutdown of information technology (IT) services, marked reduction in outpatient activity, temporary cessation of essential services such as radiation therapy. We provide a framework for other institutions for mitigating the impact of a cyberattack, underscoring the need for a cyberpreparedness plan similar to those made for natural disasters and the profound legacy of a cyberattack on patient care.

Christine Gibbs.

A pioneer of veterinary radiology, she was a born teacher and a role model.

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.

Smart needle electrical bioimpedance to provide information on needle tip relationship to target nerve prior to local anesthetic deposition in peripheral nerve block (USgPNB) procedures.

Ultrasound guided peripheral nerve block (USgPNB) refers to anaesthetic techniques to deposit local anesthetic next to nerves, permitting painful surgery without necessitating general anesthesia. Needle tip position prior to local anesthetic deposition is a key determinant of block success and safety. Nerve puncture and intra-neural injection of local anesthetic can cause permanent nerve injury. Currently ultrasound guidance is not sufficiently sensitive to reliably detect needle to nerve proximity. Feedback with bioimpedance data from the smart needle tip might provide the anesthetist with information as to the relationship between the needle tip and the target nerve prior to local anesthetic deposition. Bioimpedance using a smart needle integrated with a two-electrode impedance sensor has been developed to determine needle to nerve proximity during USgPNB. Having obtained all necessary ethical and regulatory approvals, in vivo data on brachial plexus, vagus, femoral and sciatic nerves were obtained from seven pig models using the smart needle bioimpedance system. The excision and histological analysis of above peripheral nerves and observation of the architecture and structure of nerves by means of histology allow the calculation of the ratios of connective tissue to neural tissue to determine the influence of this variable on absolute impedance. The ratio results give extra clinical data and explain the hetrogeneity of impedance data in the pig models and the hypothesis that connective tissue with intra-neural fat has higher impedance than neural tissue.

Rapid carbon accumulation at a saltmarsh restored by managed realignment exceeded carbon emitted in direct site construction.

Increasing attention is being paid to the carbon sequestration and storage services provided by coastal blue carbon ecosystems such as saltmarshes. Sites restored by managed realignment, where existing sea walls are breached to reinstate tidal inundation to the land behind, have considerable potential to accumulate carbon through deposition of sediment brought in by the tide and burial of vegetation in the site. While this potential has been recognised, it is not yet a common motivating factor for saltmarsh restoration, partly due to uncertainties about the rate of carbon accumulation and how this balances against the greenhouse gases emitted during site construction. We use a combination of field measurements over four years and remote sensing to quantify carbon accumulation at a large managed realignment site, Steart Marshes, UK. Sediment accumulated rapidly at Steart Marshes (mean of 75 mm yr-1) and had a high carbon content (4.4% total carbon, 2.2% total organic carbon), resulting in carbon accumulation of 36.6 t ha-1 yr-1 total carbon (19.4 t ha-1 yr-1 total organic carbon). This rate of carbon accumulation is an order of magnitude higher than reported in many other restored saltmarshes, and is somewhat higher than values previously reported from another hypertidal system (Bay of Fundy, Canada). The estimated carbon emissions associated with the construction of the site were ~2-4% of the observed carbon accumulation during the study period, supporting the view that managed realignment projects in such settings may have significant carbon accumulation benefits. However, uncertainties such as the origin of carbon (allochthonous or autochthonous) and changes in gas fluxes need to be resolved to move towards a full carbon budget for saltmarsh restoration.

Paediatric ankle cartilage lesions: Proceedings of the International Consensus Meeting on Cartilage Repair of the Ankle.

BACKGROUND: The evidence supporting best practice guidelines in the field of cartilage repair of the ankle are based on both low quality and low levels of evidence. Therefore, an international consensus group of experts was convened to collaboratively advance toward consensus opinions based on the best available evidence on key topics within cartilage repair of the ankle. The purpose of this article is to report the consensus statements on "Pediatric Ankle Cartilage Lesions" developed at the 2019 International Consensus Meeting on Cartilage Repair of the Ankle. METHODS: Forty-three international experts in cartilage repair of the ankle representing 20 countries convened to participate in a process based on the Delphi method of achieving consensus. Questions and statements were drafted within four working groups focusing on specific topics within cartilage repair of the ankle, after which a comprehensive literature review was performed and the available evidence for each statement was graded. Discussion and debate occurred in cases where statements were not agreed upon in unanimous fashion within the working groups. A final vote was then held, and the strength of consensus was characterised as follows: consensus: 51-74%; strong consensus: 75-99%; unanimous: 100%. RESULTS: A total of 12 statements on paediatric ankle cartilage lesions reached consensus during the 2019 International Consensus Meeting on Cartilage Repair of the Ankle. Five achieved unanimous support, and seven reached strong consensus (>75% agreement). All statements reached at least 84% agreement. CONCLUSIONS: This international consensus derived from leaders in the field will assist clinicians with the management of paediatric ankle cartilage lesions.

Shortening the Return-to-Play Times in Elite Athletes With Unstable Isolated Lisfranc Ligament Injuries Using a Knotless Interosseous Suture Button: Case Series and Literature Review.

Background: Isolated unstable Lisfranc ligament injuries in elite athletes are associated with a lengthy period of rehabilitation and prolonged absence from competition. Purpose: To assess the efficacy of a knotless, interosseous suture button system for repairing isolated unstable ligamentous Lisfranc injuries and its capacity to allow accelerated rehabilitation with earlier weightbearing and return-to-play times in elite athletes. Study Design: Case series; Level of evidence, 4. Methods: The authors retrospectively reviewed data from a prospectively compiled database for elite athletes treated by a single surgeon. All included patients had clinical and magnetic resonance imaging evidence of an unstable isolated complete ligamentous Lisfranc injury requiring surgical reduction and stabilization. All patients underwent surgery using a knotless interosseous suture button to achieve stabilization, followed by a standardized postoperative regimen involving full weightbearing at 4 weeks, and all had a minimum postoperative follow-up of 2 years. Results: Included were 12 patients: 7 National Rugby League (NRL) players, 2 professional dancers, 1 Olympic gymnast, 1 professional wakeboarder, and 1 professional NRL referee. The mean age of the patients was 21.1 years (range, 16-34 years). Ten patients underwent acute surgical stabilization within 3 weeks of the injury, and 2 patients sustained chronic isolated Lisfranc instability that was initially treated nonoperatively. All athletes were able to return to full weightbearing by 4 weeks postoperatively, successfully returned to training by 9 to 12 weeks, and returned to full competition by 12 to 16 weeks. No major complications were reported. Conclusion: Knotless interosseous suture button stabilization was a reliable treatment option for both acute and chronic isolated ligamentous Lisfranc injuries in these elite athletes. This technique does not require hardware removal, allows early weightbearing with accelerated rehabilitation, and may shorten the return-to-play interval.

Terminology for osteochondral lesions of the ankle: proceedings of the International Consensus Meeting on Cartilage Repair of the Ankle.

BACKGROUND: The evidence supporting best practice guidelines in the field of cartilage repair of the ankle is based on both low quality and low levels of evidence. Therefore, an international consensus group of experts was convened to collaboratively advance toward consensus opinions based on the best available evidence on key topics within cartilage repair of the ankle. The purpose of this article is to report the consensus statements on "terminology for osteochondral lesions of the ankle" developed at the 2019 International Consensus Meeting on Cartilage Repair of the Ankle. METHODS: Forty-three international experts in cartilage repair of the ankle representing 20 countries were convened and participated in a process based on the Delphi method of achieving consensus. Questions and statements were drafted within four working groups focusing on specific topics within cartilage repair of the ankle, after which a comprehensive literature review was performed, and the available evidence for each statement was graded. Discussion and debate occurred in cases where statements were not agreed on in unanimous fashion within the working groups. A final vote was then held, and the strength of consensus was characterised as follows: consensus, 51%-74%; strong consensus, 75%-99%; unanimous, 100%. RESULTS: A total of 11 statements on terminology and classification reached consensus during the 2019 International Consensus Meeting on Cartilage Repair of the Ankle. Definitions are provided for osseous, chondral and osteochondral lesions, as well as bone marrow stimulation and injury chronicity, among others. An osteochondral lesion of the talus can be abbreviated as OLT. CONCLUSIONS: This international consensus derived from leaders in the field will assist clinicians with the appropriate terminology for osteochondral lesions of the ankle.

The positive predictive value of vacuum assisted biopsy (VAB) in predicting final histological diagnosis for breast lesions of uncertain malignancy (B3 lesions): A systematic review & meta-analysis.

INTRODUCTION: High-risk or B3 breast lesions are considered lesions of uncertain malignant potential and comprise between 5 and 12% of initial biopsy results. We sought to perform a systematic review and meta-analysis of studies published within the last twenty years to determine the pooled Positive Predictive Value (PPV) of VAB in selected B3 lesions. METHODS: The study report is based on the guidelines of PRISMA and Meta-Analysis of Observational Studies in Epidemiology. OUTCOMES: The primary outcome of this study was to determine the PPV of VAB in determining final histological diagnosis in B3 breast lesions using pooled estimates. The secondary outcomes were to determine if needle gauge or the re-classification of Lobular Carcinoma in Situ(LCIS) introduced in 2012 influenced pooled estimates. RESULTS: 78 studies incorporating 6,377 B3 lesions were included in this review, 1214 of which were upgraded to DCIS or invasive malignancy following surgical excision(19%). The pooled PPV of VAB in Atypical Ductal Hyperplasia(ADH) and Lobular Neoplasia(LN) were 0.79(CI 0.76-0.83) and 0.84(CI 0.8-0.88). VAB of Flat Epithelial Atypia(FEA), radial scar and papillary lesions with/without atypia all had a pooled PPV >90% (underestimation rates 7%, 1%, 5% and 3% respectively). Needle gauge size and the change in LCIS classification did not appear to influence underestimation rates on subgroup analysis. CONCLUSION: Results from this meta-analysis suggests it is reasonable to perform VAB as definitive treatment for certain B3 lesions, specifically LN, FEA, radial scar, and papillary lesions when specific criteria are fulfilled. Surgical excision should continue as the mainstay of treatment for ADH.

Osteochondral Lesions of the Tibial Plafond and Ankle Instability With Ankle Cartilage Lesions: Proceedings of the International Consensus Meeting on Cartilage Repair of the Ankle.

BACKGROUND: An international consensus group of experts was convened to collaboratively advance toward consensus opinions based on the best available evidence on key topics within cartilage repair of the ankle. The purpose of this article is to present the consensus statements on osteochondral lesions of the tibial plafond (OLTP) and on ankle instability with ankle cartilage lesions developed at the 2019 International Consensus Meeting on Cartilage Repair of the Ankle. METHODS: Forty-three experts in cartilage repair of the ankle were convened and participated in a process based on the Delphi method of achieving consensus. Questions and statements were drafted within 4 working groups focusing on specific topics within cartilage repair of the ankle, after which a comprehensive literature review was performed and the available evidence for each statement was graded. Discussion and debate occurred in cases where statements were not agreed on in unanimous fashion within the working groups. A final vote was then held. RESULTS: A total of 11 statements on OLTP reached consensus. Four achieved unanimous support and 7 reached strong consensus (greater than 75% agreement). A total of 8 statements on ankle instability with ankle cartilage lesions reached consensus during the 2019 International Consensus Meeting on Cartilage Repair of the Ankle. One achieved unanimous support, and seven reached strong consensus (greater than 75% agreement). CONCLUSION: These consensus statements may assist clinicians in the management of these difficult clinical pathologies. LEVEL OF EVIDENCE: Level V, mechanism-based reasoning.

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.

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.

Morphological Assessment of MACI Grafts in Patients with Revision Surgery and Total Joint Arthroplasty.

OBJECTIVE: To compare the histological and immunohistochemical characteristics of matrix-assisted chondrocyte implantation (MACI) grafts between patients with revision surgery and patients with total joint arthroplasty. METHODS: Biopsies of MACI grafts from patients with revision and total joint arthroplasty. The graft tissue characteristics and subchondral bone were examined by qualitative histology, ICRS (International Cartilage Repair Society) II scoring and semiquantitative immunohistochemistry using antibodies specific to type I and type II collagen. RESULTS: A total of 31 biopsies were available, 10 undergoing total knee arthroplasty (TKA) and 21 patients undergoing revision surgery. Patients in the clinically failed group were significantly older (46.3 years) than patients in the revision group (36.6 years) (P = 0.007). Histologically, the predominant tissue in both groups was of fibrocartilaginous nature, although a higher percentage of specimens in the revision group contained a hyaline-like repair tissue. The percentages of type I collagen (52.9% and 61.0%) and type II collagen (66.3% and 42.2%) were not significantly different between clinically failed and revised MACI, respectively. The talar dome contained the best and patella the worst repair tissue. Subchondral bone pathology was present in all clinically failed patients and consisted of bone marrow lesions, including edema, necrosis and fibrosis, intralesional osteophyte formation, subchondral bone plate elevation, intralesional osteophyte formation, subchondral bone cyst formation, or combinations thereof. CONCLUSIONS: MACI grafts in patients with revision and total joint arthroplasty were predominantly fibrocartilage in repair type, did not differ in composition and were histologically dissimilar to healthy cartilage. Clinically failed cases showed evidence of osteochondral unit failure, rather than merely cartilage repair tissue failure. The role of the subchondral bone in relation to pain and failure and the pathogenesis warrants further investigation.